Internet Draft Network Working Group Tom Worster (Editor) INTERNET DRAFT GDC Expires Aug 1999 Feb 1999 General Switch Management Protocol <draft-worster-gsmp-00.txt> Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet- Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Acknowledgement GSMP was created by P. Newman, W. Edwards, R. Hinden, E. Hoffman, F. Ching Liaw, T. Lyon, and G. Minshall (see [6] and [7]). This version of GSMP is based on their work. Abstract This memo provides the first draft of the specification of a proposed GSMP standard. It is based on GSMP V2 [7]. Worster, et. al. Page 1] Internet Draft General Switch Management Protocol Feb 1999 Changes from the pervious draft Relative to GSMP V2 [7], the changes are as follows: - The protocol specification has been generalised from ATM switches to label switches. The VPI/VCI fields in GSMP messages have been generalised to Label fields. Currently label formats and semantics and label specific procedures are defined only for ATM ports. - Label stacking is supported by the inclusion of up to two Input Labels or two Output Labels in the connection management messages. - A placeholder has been crated for an IP encapsulation of GSMP messages. - The security considerations text has been deleted. Security considerations will be updated in the future based on the IP encapsulation work. - Three QoS Models have been introduced: the Service Model, the Simple Abstract Model and the QoS Profile Model. - The Service Model has not be introduced to this draft yet. Placeholders for Service Model definitions have been created. - A QoS Model Selector field has been added to the connection management messages that distinguishes the three QoS Models. A Service Selector Field repaces the Class of Service field. - The delay priorities of GSMP V1.1 [6] and V2 have been retained in Simple Abstract Model. - The QoS profiles of V2 have been retained in the QoS Profile Model. - Chapter 9, "QoS Messages" and its abstract model have been deleted and replaced with a placeholder for Service Model definitions. - Space has been allocated at the end of Add Branch and Move Branch Messages to accomodate traffic parameters in the Service Model. - The congestion indication flag has been removed. Worster, et. al. Page 2] Internet Draft General Switch Management Protocol Feb 1999 - Changed "Port Type" in V2 Port Config Messages to "Line Type" and reused the name "PortType" to mean "ATM", "FR" etc. - Port and All Ports Configuration messages have been generalised to allow port type specific port configuration data. Space has been created in these messages for the Service Model Data. Worster, et. al. Page 3] Internet Draft General Switch Management Protocol Feb 1999 Table of Contents 1. Introduction ..................................................... 5 2. GSMP Packet Encapsulation ........................................ 7 2.1 ATM Encapsulation ............................................ 7 2.2 Ethernet Encapsulation ....................................... 8 2.3 IP Encapsulation ............................................ 10 3. Common Definitions and Procedures ............................... 10 3.1 GSMP Packet Format .......................................... 11 3.2 Failure Response Messages ................................... 13 4. Connection Management Messages .................................. 18 4.1 General Message Definitions ................................. 18 4.2 Add Branch Message .......................................... 24 4.3 Delete Tree Message ......................................... 27 4.4 Verify Tree Message ......................................... 27 4.5 Delete All Message .......................................... 27 4.6 Delete Branches Message ..................................... 28 4.7 Move Branch Message ......................................... 30 5. Port Management Messages ........................................ 33 5.1 Port Management Message ..................................... 33 5.2 Label Range Message ......................................... 38 6. State and Statistics Messages ................................... 42 6.1 Connection Activity Message ................................. 42 6.2 Statistics Messages ......................................... 45 6.2.1 Port Statistics Message ............................... 48 6.2.2 Connection Statistics Message ......................... 48 6.2.3 QoS Class Statistics Message .......................... 48 6.3 Report Connection State Message ............................. 48 7. Configuration Messages .......................................... 54 7.1 Switch Configuration Message ................................ 54 7.2 Port Configuration Message .................................. 56 7.2.1 PortType Specific Data ................................ 57 7.3 All Ports Configuration Message ............................. 63 8. Event Messages .................................................. 64 8.1 Port Up Message ............................................. 66 8.2 Port Down Message ........................................... 66 8.3 Invalid Label Message ....................................... 66 8.4 New Port Message ............................................ 66 8.5 Dead Port Message ........................................... 67 9. Service Model Definition ........................................ 67 Worster, et. al. Page 4] Internet Draft General Switch Management Protocol Feb 1999 10. Adjacency Protocol ............................................. 67 10.1 Packet Format .............................................. 67 10.2 Procedure .................................................. 70 10.3 Loss of Synchronization .................................... 73 11. Summary of Failure Response Codes .............................. 74 12. Summary of Message Set ......................................... 76 13. Security Considerations ........................................ 77 1. Introduction The General Switch Management Protocol (GSMP), is a general purpose protocol to control a label switch. GSMP allows a controller to establish and release connections across the switch; add and delete leaves on a multicast connection; manage switch ports; request configuration information; and request statistics. It also allows the switch to inform the controller of asynchronous events such as a link going down. The GSMP protocol is asymmetric, the controller being the master and the switch being the slave. Multiple switches may be controlled by a single controller using multiple instantiations of the protocol over separate control connections. GSMP may be transported in three ways: - GSMP may run across an ATM link connecting the controller to the switch, on a control connection (virtual channel) established at initialization. - GSMP operation across an Ethernet link is specified. - GSMP operation across an IP network is specified. A label switch is a frame or cell switch that supports connection oriented switching using the exact match forwarding algorithm based on labels attached to incomming cells or frames. A switch is assumed to contain multiple "ports". Each port is a combination of one "input port" and one "output port". Some GSMP requests refer to the port as a whole whereas other requests are specific to the input port or the output port. Cells or labeled frames arrive at the switch from an external communication link on incoming labeled channels at an input port. Cells or or labeled frames depart from the switch to an external communication link on labeled channels from an output port. Worster, et. al. Page 5] Internet Draft General Switch Management Protocol Feb 1999 A switch may support multiple label types, however, each switch port can support only one label type. The label type supported by a given port is indicated by the switch to the controller in a port configuration message. Connections may be established between ports supporting different label types. Label types include ATM, Frame Relay and MPLS. A connection across a switch is formed by connecting an incoming labeled channel to one or more outgoing labeled channels. Connections are referenced by the input port on which they arrive and the Labels values of their incoming labeled channel. GSMP supports point-to-point and point-to-multipoint connections. A multipoint-to-point connection is specified by establishing multiple point-to-point connections each of them specifying the same output branch. A multipoint-to-multipoint connection is specified by establishing multiple point-to-multipoint trees each of them specifying the same output branches. In general a connection is established with a certain quality of service (QoS). This version of GSMP supports three QoS Models: a Service Model, a Simple Abstract Model and a QoS Profile Model. The Service Model is based on service definitions found external to GSMP such as in Integrated Services or ATM Service Categories. Each connection is assigned a specific service which defines the handling of the connection by the switch. Additionally, traffic parameters and traffic controls may be assigned to the connection depending on the assigned service. In the Simple Abstract Model a connection is assigned a priority when it is established. It may be assumed that for connections that share the same output port, an cell or frame on a connection with a higher priority is much more likely to exit the switch before a cell or frame on a connection with a lower priority if they are both in the switch at the same time. The number of priorities that each port of the switch supports may be obtained from the port configuration message. The QoS Profile Model provides a simple mechanism that allows connection to be assigned QoS semantics defined external to GSMP. GSMP contains an adjacency protocol. The adjacency protocol is used to synchronize state across the link, to negotiate which version of the GSMP protocol to use, to discover the identity of the entity at the other end of a link, and to detect when it changes. Worster, et. al. Page 6] Internet Draft General Switch Management Protocol Feb 1999 2. GSMP Packet Encapsulation 2.1 ATM Encapsulation GSMP packets are variable length and for an ATM data link layer they are encapsulated directly in an AAL-5 CPCS-PDU [3] with an LLC/SNAP header as illustrated: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | LLC (0xAA-AA-03) | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | SNAP (0x00-00-00-88-0C) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ GSMP Message ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Pad (0 - 47 octets) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + AAL-5 CPCS-PDU Trailer (8 octets) + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ (The convention in the documentation of Internet Protocols [5] is to express numbers in decimal. Numbers in hexadecimal format are specified by prefacing them with the characters "0x". Data is pictured in "big-endian" order. That is, fields are described left to right, with the most significant octet on the left and the least significant octet on the right. Whenever a diagram shows a group of octets, the order of transmission of those octets is the normal order in which they are read in English. Whenever an octet represents a numeric quantity the left most bit in the diagram is the high order or most significant bit. That is, the bit labeled 0 is the most significant bit. Similarly, whenever a multi-octet field represents a numeric quantity the left most bit of the whole field is the most significant bit. When a multi-octet quantity is transmitted, the most significant octet is transmitted first. This is the same coding convention as is used in the ATM layer [2] and AAL-5 [3].) The LLC/SNAP header contains the octets: 0xAA 0xAA 0x03 0x00 0x00 0x00 0x88 0x0C. (0x880C is the assigned Ethertype for GSMP.) The maximum transmission unit (MTU) of the GSMP Message field is 1492 octets. Worster, et. al. Page 7] Internet Draft General Switch Management Protocol Feb 1999 The virtual channel over which a GSMP session is established between a controller and the switch it is controlling is called the GSMP control channel. The default VPI and VCI of the GSMP control channel for LLC/SNAP encapsulated GSMP messages on an ATM data link layer is: VPI = 0 VCI = 15. 2.2 Ethernet Encapsulation GSMP packets may be encapsulated on an Ethernet data link as illustrated: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Destination Address | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | Source Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Ethertype (0x88-0C) | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | ~ GSMP Message ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sender Instance | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Receiver Instance | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Pad | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Frame Check Sequence | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Destination Address For the SYN message of the adjacency protocol the Destination Address is the broadcast address 0xFFFFFFFFFFFF. (Alternatively, it is also valid to configure the node with the unicast 48-bit IEEE MAC address of the destination. In this case the configured unicast Destination Address is used in the SYN message.) For all other messages the Destination Address is the unicast 48- bit IEEE MAC address of the destination. This address may be discovered from the Source Address Worster, et. al. Page 8] Internet Draft General Switch Management Protocol Feb 1999 field of messages received during synchronization of the adjacency protocol. Source Address For all messages the Source Address is the 48-bit IEEE MAC address of the sender. Ethertype The assigned Ethertype for GSMP is 0x880C. GSMP Message The maximum transmission unit (MTU) of the GSMP Message field is 1492 octets. Sender Instance The Sender Instance number for the link obtained from the adjacency protocol. This field is already present in the adjacency protocol message. It is appended to all non- adjacency GSMP messages in the Ethernet encapsulation to offer additional protection against the introduction of corrupt state. Receiver Instance The Receiver Instance number is what the sender believes is the current instance number for the link, allocated by the entity at the far end of the link. This field is already present in the adjacency protocol message. It is appended to all non-adjacency GSMP messages in the Ethernet encapsulation to offer additional protection against the introduction of corrupt state. Pad The minimum length of the data field of an Ethernet packet is 46 octets. If necessary, padding should be added such that it meets the minimum Ethernet frame size. This padding should be octets of zero and it is not considered to be part of the GSMP message. After the adjacency protocol has achieved synchronization, for every GSMP message received with an Ethernet encapsulation, the receiver must check the Source Address from the Ethernet MAC header, the Sender Instance, and the Receiver Instance. The incoming GSMP message must be discarded if the Sender Instance and the Source Address do not match the values of Sender Instance and Sender Name stored by the "Update Peer Verifier" operation of the GSMP adjacency protocol. The incoming GSMP message must also be discarded if it arrives over any port other than the port over which the adjacency protocol has achieved synchronization. In addition, the incoming message must also be discarded if the Worster, et. al. Page 9] Internet Draft General Switch Management Protocol Feb 1999 Receiver Instance field does not match the current value for the Sender Instance of the GSMP adjacency protocol. 2.3 IP Encapsulation 3. Common Definitions and Procedures GSMP is a master-slave protocol. The controller issues request messages to the switch. Each request message indicates whether a response is required from the switch and contains a transaction identifier to enable the response to be associated with the request. The switch replies with a response message indicating either a successful result or a failure. There are five classes of GSMP request-response message: Connection Management, Port Management, State and Statistics, Configuration, and Quality of Service. The switch may also generate asynchronous Event messages to inform the controller of asynchronous events. Event messages are not acknowledged by the controller. There is also an adjacency protocol message used to establish synchronization across the link and maintain a handshake. For the request-response messages, each message type has a format for the request message and a format for the success response. Unless otherwise specified a failure response message is identical to the request message that caused the failure, with the Code field indicating the nature of the failure. Event messages have only a single format defined as they are not acknowledged by the controller. Switch ports are described by a 32-bit port number. The switch assigns port numbers and it may typically choose to structure the 32 bits into subfields that have meaning to the physical structure of the switch (e.g. slot, port). In general, a port in the same physical location on the switch will always have the same port number, even across power cycles. The internal structure of the port number is opaque to the GSMP protocol. However, for the purposes of network management such as logging, port naming, and graphical representation, a switch may declare the physical location (physical slot and port) of each port. Alternatively, this information may be obtained by looking up the product identity in a database. Each switch port also maintains a port session number assigned by the switch. A message, with an incorrect port session number must be rejected. This allows the controller to detect a link failure and to keep state synchronized. Worster, et. al. Page 10] Internet Draft General Switch Management Protocol Feb 1999 Except for the adjacency protocol message, no GSMP messages may be sent across the link until the adjacency protocol has achieved synchronization, and all GSMP messages received on a link that does not currently have state synchronization must be discarded. 3.1 GSMP Packet Format All GSMP messages, except the adjacency protocol message, have the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Message Body ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Version The version number of the GSMP protocol being used in this session. It should be set by the sender of the message to the GSMP protocol version negotiated by the adjacency protocol. Message Type The GSMP message type. GSMP messages fall into six classes: Connection Management, Port Management, State and Statistics, Configuration, Quality of Service, and Events. Each class has a number of different message types. In addition, one Message Type is allocated to the adjacency protocol. Result Field in a Connection Management request message, a Port Management request message, or a Quality of Service request message is used to indicate whether a response is required to the request message if the outcome is successful. A value of "NoSuccessAck" indicates that the request message does not expect a response if the outcome is successful, and a value of "AckAll" indicates that a response is expected if the outcome is successful. In both cases a failure response must be generated if the request fails. For Sate and Statistics, and Configuration request messages, a value of "NoSuccessAck" in the request message is ignored and the Worster, et. al. Page 11] Internet Draft General Switch Management Protocol Feb 1999 request message is handled as if the field were set to "AckAll". (This facility was added to reduce the control traffic in the case where the controller periodically checks that the state in the switch is correct. If the controller does not use this capability, all request messages should be sent with a value of "AckAll.") In a response message the result field can have three values: "Success," "More," and "Failure". The "Success" and "More" results both indicate a success response. The "More" result indicates that the success response exceeds the maximum transmission unit of the data link and that one or more further messages will be sent to complete the success response. All messages that belong to the same success response will have the same Transaction Identifier. The "Success" result indicates a success response that may be contained in a single message or the final message of a success response spanning multiple messages. The encoding of the result field is: NoSuccessAck: Result = 1 AckAll: Result = 2 Success: Result = 3 Failure: Result = 4 More: Result = 5. The Result field is not used in an adjacency protocol message. Code Field gives further information concerning the result in a response message. It is mostly used to pass an error code in a failure response but can also be used to give further information in a success response message or an event message. In a request message the code field is not used and is set to zero. In an adjacency protocol message the Code field is used to determine the function of the message. Transaction Identifier Used to associate a request message with its response message. For request messages the controller may select any transaction identifier. For response messages the transaction identifier is set to the value of the transaction identifier from the message to which it is a response. For event messages the transaction identifier should be set to zero. The Transaction Identifier is not Worster, et. al. Page 12] Internet Draft General Switch Management Protocol Feb 1999 used, and the field is not present, in the adjacency protocol. The following fields are frequently found in GSMP messages. They are defined here to avoid repetition. Port Gives the port number of the switch port to which the message applies. Port Session Number Each switch port maintains a Port Session Number assigned by the switch. The port session number of a port remains unchanged while the port is continuously in the Available state and the link status is continuously Up. When a port returns to the Available state after it has been Unavailable or in any of the Loopback states, or when the line status returns to the Up state after it has been Down or in Test, or after a power cycle, a new Port Session Number must be generated. Port session numbers should be assigned using some form of random number. If the Port Session Number in a request message does not match the current Port Session Number for the specified port, a failure response message must be returned with the Code field indicating, "Invalid port session number." The current port session number for a port may be obtained using a Port Configuration or an All Ports Configuration message. Any field in a GSMP message that is unused or defined as "reserved" must be set to zero by the sender and ignored by the receiver. It is not an error for a GSMP message to contain additional data after the end of the Message Body. This is to support development and experimental purposes. However, the maximum transmission unit of the GSMP message, as defined by the data link layer encapsulation, must not be exceeded. A success response message must not be sent until the requested operation has been successfully completed. 3.2 Failure Response Messages [Editor's note: this section has not been updated in this revision. this section will be updated once more work on new functions has been added.] Worster, et. al. Page 13] Internet Draft General Switch Management Protocol Feb 1999 A failure response message is formed by returning the request message that caused the failure with the Result field in the header indicating failure (Result = 4) and the Code field giving the failure code. The failure code specifies the reason for the switch being unable to satisfy the request message. If the switch issues a failure response in reply to a request message, no change should be made to the state of the switch as a result of the message causing the failure. (For request messages that contain multiple requests, such as the Delete Branches message, the failure response message will specify which requests were successful and which failed. The successful requests may result in changed state.) If the switch issues a failure response it must choose the most specific failure code according to the following precedence: Invalid Message Failure specific to the particular message type (failure code 16). (The meaning of this failure is dependent upon the particular message type and is specified in the text defining the message.) A failure response specified in the text defining the message type. Connection Failures Virtual Path Connection Failures Multicast Failures QoS Failures (QoS failures are specified in Section 9.7.) General Failures If multiple failures match in any of the following categories, the one that is listed first should be returned. The following failure response messages and failure codes are defined: Invalid Message 3: The specified request is not implemented on this switch. The Message Type field specifies a message that is not implemented on the switch or contains a value that is Worster, et. al. Page 14] Internet Draft General Switch Management Protocol Feb 1999 not defined in the version of the protocol running in this session of GSMP. 5: One or more of the specified ports does not exist. At least one of the ports specified in the message is invalid. A port is invalid if it does not exist or if it has been removed from the switch. 4: Invalid Port Session Number. The value given in the Port Session Number field does not match the current Port Session Number for the specified port. Connection Failures 8: The specified connection does not exist. An operation that expects a connection to be specified cannot locate the specified connection. A connection is specified by the input port and input label on which it arrives. An ATM virtual path connection is specified by the input port and input VPI on which it arrives. 9: The specified branch does not exist. An operation that expects a branch of an existing connection to be specified cannot locate the specified branch. A branch of a connection is specified by the connection it belongs to and the output port and output label on which it departs. A branch of an ATM virtual path connection is specified by the virtual path connection it belongs to and the output port and output VPI on which it departs. 18: One or more of the specified input VPIs is invalid. 19: One or more of the specified Input Labels is invalid. 20: One or more of the specified output VPIs is invalid. 21: One or more of the specified Output Labelss is invalid. 22: Invalid Service Selector field in a Connection Management message. The value of the Service Selector field is invalid. 23: Insufficient resources for QoS Profile. The resources requested by the QoS Profile in the Service Selector field are not available. Worster, et. al. Page 15] Internet Draft General Switch Management Protocol Feb 1999 ATM Virtual Path Connections 24: ATM virtual path switching is not supported on this input port. 25: Point-to-multipoint ATM virtual path connections are not supported on either the requested input port or the requested output port. One or both of the requested input and output ports is unable to support point-to-multipoint ATM virtual path connections. 26: Attempt to add a ATM virtual path connection branch to an existing virtual channel connection. It is invalid to mix branches switched as virtual channel connections with branches switched as ATM virtual path connections on the same point-to- multipoint connection. 27: Attempt to add a virtual channel connection branch to an existing ATM virtual path connection. It is invalid to mix branches switched as virtual channel connections with branches switched as ATM virtual path connections on the same point-to- multipoint connection. XX: ATM Virtual path switching is not supported on non-ATM ports. One or both of the requested input and output ports is not an ATM port. ATM virtual path switching is only supported on ATM ports. Multicast Failures 10: A branch belonging to the specified point-to-multipoint connection is already established on the specified output port and the switch cannot support more than a single branch of any point-to-multipoint connection on the same output port. 11: The limit on the maximum number of point-to-multipoint connections that the switch can support has been reached. 12: The limit on the maximum number of branches that the specified point-to-multipoint connection can support has been reached. Worster, et. al. Page 16] Internet Draft General Switch Management Protocol Feb 1999 17: Cannot label each output branch of a point-to-multipoint tree with a different label. Some early designs, and some low-cost switch designs, require all output branches of a multicast connection to use the same value of Label. 28: Only point-to-point bidirectional connections may be established. It is an error to attempt to add an additional output branch to an existing connection with the bidirectional flag set. 13: Unable to assign the requested Label value to the requested branch on the specified point-to-multipoint connection. Although the requested Labels are valid, the switch is unable to support the request using the specified Label values for some reason not covered by the above failure responses. This message implies that a valid value of Lable exists that the switch could support. For example, some switch designs restrict the number of distinct Label values available to a point-to- multipoint connection. (Most switch designs will not require this message.) 14: General problem related to the manner in which point-to- multipoint is supported by the switch. Use this message if none of the more specific multicast failure messages apply. (Most switch designs will not require this message.) General Failures 2: Invalid request message. There is an error in one of the fields of the message not covered by a more specific failure message. 6: One or more of the specified ports is down. A port is down if its Port Status is Unavailable. Connection Management, Connection State, Port Management, and Configuration operations are permitted on a port that is Unavailable. Connection Activity and Statistics operations are not permitted on a port that is Unavailable and will generate this failure response. A Port Management message specifying a Take Down function on a port already in the Unavailable state will also generate this failure response. Worster, et. al. Page 17] Internet Draft General Switch Management Protocol Feb 1999 15: Out of resources. The switch has exhausted a resource not covered by a more specific failure message, for example, running out of memory. 1: Unspecified reason not covered by other failure codes. The failure message of last resort. The following failure response messages are only used by the Label Range message. [Must come back and revise this --ed] 29: Cannot support requested VPI range. 30: Cannot support requested VCI range on all requested VPIs. The following failure response messages are only used by the Set Transmit Cell Rate function of the Port Management message. 31: The transmit cell rate of this output port cannot be changed. 32: Requested transmit cell rate out of range for this output port. 4. Connection Management Messages 4.1 General Message Definitions Connection management messages are used by the controller to establish, delete, modify and verify connections across the switch. The Add Branch, Delete Tree, and Delete All connection management messages have the following format for both request and response messages: Worster, et. al. Page 18] Internet Draft General Switch Management Protocol Feb 1999 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Session Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Input Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |M|B|E|x| | +-+-+-+-+ Input Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Output Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |QMS|E|x| | +-+-+-+-+ Output Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Number of Branches | Service Selector | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Input PortIdentifies a switch input port. Flags M: Multicast Multicast flag is used as a hint for point-to- multipoint connections in the Add Branch message. It is not used in any other connection management messages and in these messages it should be set to zero. If set, it indicates that the virtual channel connection or the virtual path connection is very likely to be a point-to-multipoint connection. If zero, it indicates that this connection is very likely to be a point-to-point connection or is unknown. The Multicast flag is only used in the Add Branch message when establishing the first branch of a new connection. It is not required to be set when establishing subsequent branches of a point-to- multipoint connection and on such connections it should be ignored by the receiver. (On receipt of the second and subsequent Add Branch messages the receiver knows that this is a point-to-multipoint connection.) Worster, et. al. Page 19] Internet Draft General Switch Management Protocol Feb 1999 If it is known that this is the first branch of a point-to-multipoint connection this flag should be set. If it is unknown, or if it is known that the connection is point-to-point this flag should be zero. The use of this flag is not mandatory. It may be ignored by the switch. If unused the flag should be set to zero. Some switches use a different data structure for point-to-multipoint connections than for point-to-point connections. This flag avoids the switch setting up a point-to-point structure for the first branch of a point-to-multipoint connection which must immediately be deleted and reconfigured as point- to-multipoint when the second branch is established. QMS: QoS Model Selector The QoS Model Selector is used to specify a QoS Model for connection. The value of QMS indicates the value in the Service Selector should be interprested as a priority, a QoS profile or a service specification as shown: QMS QoS Model Service Selector --- --------- ---------------- 00 Simple Abstract Model Priority 01 QoS Profile Model QoS Profile 10 Service Model Service Specification 11 Reserved N/A B: Bidirectional The Bidirectional flag applies only to the Add Branch message. In all other Connection Management messages it is not used. It may only be used when establishing a point- to-point connection. The Bidirectional flag in an Add Branch message, if set, requests that two unidirectional virtual channels or virtual paths be established, one in the forward direction, and one in the reverse direction. It is equivalent to two Add Branch messages, one specifying the forward direction, and one specifying the reverse direction. The forward direction uses the values of Input Port, Input Label, Output Port and Output Label as specified in the Add Branch message. The reverse direction is derived by exchanging the values specified in the Input Port and Input Label fields, with those of the Output Port and Output Label fields respectively. Thus, a connection in the reverse direction arrives at the input port specified by the Output Port field, on the label specified by the Output Label field. It departs from the Worster, et. al. Page 20] Internet Draft General Switch Management Protocol Feb 1999 output port specified by the Input Port field, on the label specified by the Input Label field. The Bidirectional flag is simply a convenience to establish two unidirectional connections in opposite directions between the same two ports, with identical Labels, using a single Add Branch message. In all future messages the two unidirectional connections must be handled separately. There is no bidirectional delete message. However, a single Delete Branches message with two Delete Branch Elements, one for the forward connection and one for the reverse, may be used. E: Extension Label The Extension Label flag if zero indicates that the adjacent Label field is a 28 bit field. If the Extension Label flag is set then the adjacent Label field is a 60 bit field structured as a 28 bit first level label field followed by a 32 bit second level label field. x: Unused Input Label Identifies an incomming labeled channel arriving at the switch input port indicated by the Input Port field. The value in the Input Label field must be interpreted according to the Lable Type attribute of the switch input port indicated by the Input Port field. Output Port Identifies a switch output port. Output Label Identifies an outgoing labeled channel departing at the switch output port indicated by the Output Port field. The value in the Output Label field must be interpreted according to the Lable Type attribute of the switch input port indicated by the Output Port field. Number of Branches In a success response message and a failure response message, gives the number of output branches on a connection after completion of the requested operation. (A point-to-point connection will have one branch, a point-to-multipoint connection will have two or more branches.) If the switch is unable to keep track of the number of branches on a virtual path connection or a virtual channel connection it must respond with the Worster, et. al. Page 21] Internet Draft General Switch Management Protocol Feb 1999 value 0xFFFF meaning: "number of branches unknown". This field is not used in the request message. Service Selector This field can contain either a QoS Profile Identifier, a Priority, or a Service Specification. If the QoS Model Selector is set to 0b00, the Service Selector field contains a Priority. If the QoS Model Selector is set to 0b01, the Service Selector field contains a QoS Profile. If the QoS Model Selector is set to 0b10, the Service Selector field contains a Service Specification. The Service Selector field is only used in the Add Branch and Move Branch messages. A Priority specifies the priority of the connection for Add Branch and Move Branch messages that choose not to use a QoS profile, or the QoS capabilities defined in Section 9, "Quality of Service Messages." The highest priority is numbered zero and the lowest priority is numbered "Q-1" where "Q" is the number of priorities that the output port can support. The ability to offer different qualities of service to different connections based upon their priority is assumed to be a property of the output port of the switch. It is assumed that for virtual path connections or virtual channel connections that share the same output port, a cell or frame on a connection with a higher priority is much more likely to exit the switch before a cell or frame on a connection with a lower priority, if they are both in the switch at the same time. The number of priorities that each output port can support is given in the Port Configuration message. A QoS Profile Identifier is an opaque 16-bit value. It is used to identify a QoS profile in the switch which specifies the Quality of Service required by the connection. QoS profiles are established by a mechanism external to GSMP. A Service Specification is an alternative method of communicating the QoS requirements of a connection. The Service Specification is defined in Section 9 "Service Model Definition". For all connection management messages, except the Delete Branches message, the success response message is a copy of the request message returned with the Result field indicating success and the Number of Branches field indicating the number of branches on the Worster, et. al. Page 22] Internet Draft General Switch Management Protocol Feb 1999 connection after completion of the operation. The Code field is not used in a connection management success response message. The failure response message is a copy of the request message returned with a Result field indicating failure and the Number of Branches field indicating the number of branches on the connection. Fundamentally, no distinction is made between point-to-point and point-to-multipoint connections. By default, the first Add Branch message for a particular Input Port and Input Label will establish a point-to-point connection. The second Add Branch message with the same Input Port and Input Label fields will convert the connection to a point-to-multipoint connection with two branches. However, to avoid possible inefficiency with some switch designs, the Multicast Flag is provided. If the controller knows that a new connection is point-to-multipoint when establishing the first branch, it may indicate this in the Multicast Flag. Subsequent Add Branch messages with the same Input Port and Input Label fields will add further branches to the point-to-multipoint connection. Use of the Delete Branch message on a point-to-multipoint connection with two branches will result in a point-to-point connection. However, the switch may structure this connection as a point-to-multipoint connection with a single output branch if it chooses. (For some switch designs this structure may be more convenient.) Use of the Delete Branch message on a point-to-point connection will delete the point-to-point connection. There is no concept of a connection with zero output branches. All connections are unidirectional, one input labeled channel to one or more output labeled channels. GSMP supports point-to-point and point-to-multipoint connections. A multipoint-to-point connection is specified by establishing multiple point-to-point connections each of them specifying the same output branch. (An output branch is specified by an output port and output label.) Label stacking is a technique used in MPLS that allows hierarchical labeling. MPLS label staching is similar to but subtley different from the VPI/VCI hierarchy of labels in ATM. ... [Must add blah --Ed] The connection management messages may be issued regardless of the Port Status of the switch port. Connections may be established or deleted when a switch port is in the Available, Unavailable, or any of the Loopback states. However, all connection state on an input port will be deleted when the port returns to the Available state from any other state, i.e. when a Port Management message is Worster, et. al. Page 23] Internet Draft General Switch Management Protocol Feb 1999 received for that port with the Function field indicating either Bring Up, or Reset Input Port. ATM Labels If a port's attribute PortType=ATM then that port's labels must be interpreted as ATM Labels as shown: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + - - -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | VPI | VCI | + - - -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ATM ports do not support Extension Lables so the VPI and VCI values always occupy the 28 bits following the flags in a connection management message. ATM distinguishes between virtual path connections and virtual channel connections. The connection management messages apply both to virtual channel connections and virtual path connections. The Add Branch and Move Branch connection management messages have two Message Types. One Message Type indicates that a virtual channel connection is required, and the other Message Type indicates that a virtual path connection is required. The Delete Branches, Delete Tree, and Delete All connection management messages have only a single Message Type because they do not need to distinguish between virtual channel connections and virtual path connections. For virtual path connections, neither Input VCI fields nor Output VCI fields are required. They should be set to zero by the sender and ignored by the receiver. Virtual channel branches may not be added to an existing virtual path connection. Conversely, virtual path branches may not be added to an existing virtual channel connection. In the Port Configuration message each switch input port may declare whether it is capable of supporting virtual path switching (i.e. accepting connection management messages requesting virtual path connections). Other Labels [Editor's Note: No other label types are currently defined.] 4.2 Add Branch Message The Add Branch message is a connection management message used to establish a connection or to add an additional branch to an Worster, et. al. Page 24] Internet Draft General Switch Management Protocol Feb 1999 existing connection. It may also be used to check the connection state stored in the switch. The connection is specified by the Input Port and Input Label fields. The output branch is specified by the Output Port and Output Label fields. The quality of service requirements of the connection are specified by the QoS Model Selector and Service Selector fields. To request a connection the Add Branch message is: Message Type = 16 If the connection specified by the Input Port and Input Label fields does not already exist, it must be established with the single output branch specified in the request message. If the Bidirectional Flag in the Flags field is set, the reverse connection must also be established. The output branch should have the QoS attributes specified by the Class of Service field. If the connection specified by the Input Port and Input Label fields already exists, but the specified output branch does not, the new output branch must be added. The new output branch should have the QoS attributes specified by the Class of Service field. If the connection specified by the Input Port and Input Label fields already exists and the specified output branch also already exists, the QoS attributes of the connection, specified by the Class of Service field, if different from the request message, should be changed to that in the request message. A success response message must be sent if the Result field of the request message is "AckAll". This allows the controller to periodically reassert the state of a connection or to change its priority. If the result field of the request message is "NoSuccessAck" a success response message should not be returned. This may be used to reduce the traffic on the control link for messages that are reasserting previously established state. For messages that are reasserting previously established state, the switch must always check that this state is correctly established in the switch hardware (i.e. the actual connection tables used to forward cells). If the output branch specified by the Output Port and Output Label fields is already in use by any connection other than that specified by the Input Port and Input Label fields, then the resulting output branch will have multiple input branches. If multiple point-to-point connections share the same output branch the result will be a multipoint-to-point connection. If the connection specified by the Input Port and Input Label fields already exists, and the Bidirectional Flag in the Flags field is set, a failure response must be returned indicating: Worster, et. al. Page 25] Internet Draft General Switch Management Protocol Feb 1999 "Only point-to-point bidirectional connections may be established." It should be noted that different switches support multicast in different ways. There will be a limit to the total number of point- to-multipoint connections any switch can support, and possibly a limit on the maximum number of branches that a point- to-multipoint connection may specify. Some switches also impose a limit on the number of different Label values that may be assigned to the output branches of a point-to-multipoint connection. Many switches are incapable of supporting more than a single branch of any particular point-to-multipoint connection on the same output port. Specific failure codes are defined for some of these conditions. ATM specific procedures: To request an ATM virtual path connection the ATM Virtual Path Connection (VPC) Add Branch message is: Message Type = 26 An ATM virtual path connection can only be established between ATM ports, i.e. ports with the "ATM" Label Type attribute. If an ATM VPC Add Branch message is received and either the switch input port specified by the Input Port field or the switch output port specified by the Output Port field is not an ATM port, a failure response message must be returned indicating, "Virtual path switching is not supported on non-ATM ports." If an ATM VPC Add Branch message is received and the switch input port specified by the Input Port field does not support virtual path switching, a failure response message must be returned indicating, "Virtual path switching is not supported on this input port." If an ATM virtual path connection already exists on the virtual path specified by the Input Port and Input VPI fields, a failure response message must be returned indicating, "Attempt to add a virtual channel connection branch to an existing virtual path connection." For the VPC Add Branch message, if a virtual channel connection already exists on any of the virtual channels within the virtual path specified by the Input Port and Input VPI fields, a failure response message must be returned indicating, "Attempt to add a virtual path connection branch to an existing virtual channel connection." Worster, et. al. Page 26] Internet Draft General Switch Management Protocol Feb 1999 4.3 Delete Tree Message The Delete Tree message is a connection management message used to delete an entire connection. All remaining branches of the connection are deleted. A connection is specified by the Input Port and Input Label fields. The Output Port and Output Label fields are not used in this message. The Delete Tree message is: Message Type = 18 If the Result field of the request message is "AckAll" a success response message must be sent upon successful deletion of the specified connection. The success message must not be sent until the delete operation has been completed and if possible, not until all data on the connection, queued for transmission, has been transmitted. The Number of Branches field is not used in either the request or response messages of the Delete Tree message. 4.4 Verify Tree Message The Verify Tree message has been removed from this version of GSMP. Its function has been replaced by the Number of Branches field in the success response to the Add Branch message which contains the number of branches on a connection after successful completion of an add branch operation. Message Type = 19 is reserved. If a request message is received with Message Type = 19 a failure response must be returned with the Code field indicating: "The specified request is not implemented in this version of the protocol." 4.5 Delete All Message The Delete All message is a connection management message used to delete all connections on a switch input port. All connections that arrive at the specified input port must be deleted. On completion of the operation all dynamically assigned Label values for the specified port must be unassigned, i.e. there must be no connections established in the Label space that GSMP controls on this port. The Input Label and Output Label fields are not used in this message. The Delete All message is: Message Type = 20 If the Result field of the request message is "AckAll" a success response message must be sent upon completion of the operation. The Number of Branches field is not used in either the request or Worster, et. al. Page 27] Internet Draft General Switch Management Protocol Feb 1999 response messages of the Delete All message. The success response message must not be sent until the operation has been completed. The following failure response messages may be returned to a Delete All request. The specified request is not implemented on this switch. One or more of the specified ports does not exist. Invalid Port Session Number. If any field in a Delete All message not covered by the above failure codes is invalid, a failure response must be returned indicating: "Invalid request message." Else, the delete all operation must be completed successfully and a success message returned. No other failure messages are permitted. 4.6 Delete Branches Message The Delete Branches message is a connection management message used to request one or more delete branch operations. Each delete branch operation deletes a branch of a channel, or in the case of the last branch of a connection, it deletes the connection. The Delete Branches message is: Message Type = 17 The request message has the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | Number of Elements | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Delete Branch Elements ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Number of Elements Specifies the number of Delete Branch Elements to follow in the message. The number of Delete Branch Elements in a Delete Branches message must not cause the packet Worster, et. al. Page 28] Internet Draft General Switch Management Protocol Feb 1999 length to exceed the maximum transmission unit defined by the encapsulation. Each Delete Branch Element specifies an output branch to be deleted and has the following structure: +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Session Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Input Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |x x|I|O| | +-+-+-+-+ Input Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Output Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Error | | +-+-+-+-+ Output Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ I: Input Extension Label The Input Extension Label flag if zero indicates that the Input Label field is a 28 bit field. If the Input Extension Label flag is set then the Input Label field is a 60 bit field structured as a 28 bit first level label field followed by a 32 bit second level label field. O: Output Extension Label The Output Extension Label flag if zero indicates that the Output Label field is a 28 bit field. If the Output Extension Label flag is set then the Output Label field is a 60 bit field structured as a 28 bit first level label field followed by a 32 bit second level label field. Error Is used to return a failure code indicating the reason for the failure of a specific Delete Branch Element in a Delete Branches failure response message. The Error field is not used in the request message and must be set to zero. A value of zero is used to indicate that the delete operation specified by this Delete Branch Element was successful. Values for the other failure codes are specified in Section 3.2, "Failure Response Messages." Worster, et. al. Page 29] Internet Draft General Switch Management Protocol Feb 1999 All other fields of the Delete Branch Element have the same definition as specified for the other connection management messages. In each Delete Branch Element, a connection is specified by the Input Port and Input Label fields. The specific branch to be deleted is indicated by the Output Port and Output Label fields. If the Result field of the Delete Branches request message is "AckAll" a success response message must be sent upon successful deletion of the branches specified by all of the Delete Branch Elements. The success response message must not be sent until all of the delete branch operations have been completed. The success response message is only sent if all of the requested delete branch operations were successful. No Delete Branch Elements are returned in a Delete Branches success response message and the Number of Elements field must be set to zero. If there is a failure in any of the Delete Branch Elements a Delete Branches failure response message must be returned. The Delete Branches failure response message is a copy of the request message with the Code field of the entire message set to, "Failure specific to the particular message type," and the Error field of each Delete Branch Element indicating the result of each requested delete operation. A failure in any of the Delete Branch Elements must not interfere with the processing of any other Delete Branch Elements. 4.7 Move Branch Message The Move Branch message is used to move a branch of an existing connection from its current output port label to a new output port label in a single atomic transaction. The Move Branch connection management message has the following format for both request and response messages: Worster, et. al. Page 30] Internet Draft General Switch Management Protocol Feb 1999 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Session Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Input Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |x x|E|x| | +-+-+-+-+ Input Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Old Output Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |x x|E|x| | +-+-+-+-+ Old Output Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | New Output Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |QMS|E|x| | +-+-+-+-+ New Output Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Number of Branches | Service Selector | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The E, QMS and Service Selector fields are as defined in the Add Branch message. The Move Branch message is a connection management message used to move a single output branch of connection from its current output port and Output Label, to a new output port and Output Label on the same connection. None of the connection's other output branches are modified. When the operation is complete the original Output Label on the original output port will be deleted from the connection. The Move Branch message is: Message Type = 22 For the Move Branch message, if the connection specified by the Input Port and Input Label fields already exists, and the output Worster, et. al. Page 31] Internet Draft General Switch Management Protocol Feb 1999 branch specified by the Old Output Port and Old Output Label fields exists as a branch on that connection, the output branch specified by the New Output Port and New Output Label fields is added to the connection and the branch specified by the Old Output Port and Old Output Label fields is deleted. If the Result field of the request message is "AckAll" a success response message must be sent upon successful completion of the operation. The success response message must not be sent until the Move Branch operation has been completed. For the Move Branch message, if the connection specified by the Input Port and Input Label fields already exists, but the output branch specified by the Old Output Port and Old Output Label fields does not exist as a branch on that connection, a failure response must be returned with the Code field indicating, "The specified branch does not exist." For the Move Branch message, if the connection specified by the Input Port and Input Label fields already exists, and the output branch specified by the Old Output Port and Old Output Label fields exists as a branch on that connection, the output branch specified by the New Output Port and New Output Label fields is added to the connection and the branch specified by the Old Output Port and Old Output Label fields is deleted. If the Result field of the request message is "AckAll" a success response message must be sent upon successful completion of the operation. The success response message must not be sent until the Move Branch operation has been completed. ATM Specific Procedures: The ATM VPC Move Branch message is a connection management message used to move a single output branch of a virtual path connection from its current output port and output VPI, to a new output port and output VPI on the same virtual channel connection. None of the other output branches are modified. When the operation is complete the original output VPI on the original output port will be deleted from the connection. The VPC Move Branch message is: Message Type = 27 For the VPC Move Branch message, if the virtual path connection specified by the Input Port and Input VPI fields already exists, and the output branch specified by the Old Output Port and Old Output VPI fields exists as a branch on that connection, the output branch specified by the New Worster, et. al. Page 32] Internet Draft General Switch Management Protocol Feb 1999 Output Port and New Output VPI fields is added to the connection and the branch specified by the Old Output Port and Old Output VPI fields is deleted. If the Result field of the request message is "AckAll" a success response message must be sent upon successful completion of the operation. The success response message must not be sent until the Move Branch operation has been completed. For the VPC Move Branch message, if the virtual path connection specified by the Input Port and Input VPI fields already exists, but the output branch specified by the Old Output Port and Old Output VPI fields does not exist as a branch on that connection, a failure response must be returned with the Code field indicating, "The specified branch does not exist." If the virtual channel connection specified by the Input Port and Input Label fields; or the virtual path connection specified by the Input Port and Input VPI fields; does not exist, a failure response must be returned with the Code field indicating, "The specified connection does not exist." If the output branch specified by the New Output Port, New Output VPI, and New Output VCI fields for a virtual channel connection; or the output branch specified by the New Output Port and New Output VPI fields for a virtual path connection; is already in use by any connection other than that specified by the Input Port and Input Label fields then the resulting output branch will have multiple input branches. If multiple point-to-point connections share the same output branch the result will be a multipoint-to-point connection. If multiple point-to-multipoint trees share the same output branches the result will be a multipoint-to- multipoint connection. 5. Port Management Messages 5.1 Port Management Message The Port Management message allows a port to be brought into service, taken out of service, looped back, reset, or the transmit cell rate changed. Only the Bring Up and the Reset Input Port functions change the connection state (established connections) on the input port. Only the Bring Up function changes the value of the Port Session Number. If the Result field of the request message is "AckAll" a success response message must be sent upon successful completion of the operation. The success response Worster, et. al. Page 33] Internet Draft General Switch Management Protocol Feb 1999 message must not be sent until the operation has been completed. The Port Management Message is: Message Type = 32 The Port Management message has the following format for the request and success response messages: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Session Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Event Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Event Flags | Duration | Function | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transmit Cell Rate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Event Sequence Number In the success response message gives the current value of the Event Sequence Number of the switch port indicated by the Port field. The Event Sequence Number is set to zero when the port is initialized. It is incremented by one each time the port detects an asynchronous event that the switch would normally report via an Event message. If the Event Sequence Number in the success response differs from the Event Sequence Number of the most recent Event message received for that port, events have occurred that were not reported via an Event message. This is most likely to be due to the flow control that restricts the rate at which a switch can send Event messages for each port. In the request message this field is not used. Event FlagsField in the request message is used to reset the Event Flags in the switch port indicated by the Port field. Each Event Flag in a switch port corresponds to a type of Event message. When a switch port sends an Event message it sets the corresponding Event Flag on that port. The port is not permitted to send another Event Worster, et. al. Page 34] Internet Draft General Switch Management Protocol Feb 1999 message of the same type until the Event Flag has been reset. If the Function field in the request message is set to "Reset Event Flags," for each bit that is set in the Event Flags field, the corresponding Event Flag in the switch port is reset. The Event Flags field is only used in a request message with the Function field set to "Reset Event Flags." For all other values of the Function field, the Event Flags field is not used. In the success response message the Event Flags field must be set to the current value of the Event Flags for the port, after the completion of the operation specified by the request message, for all values of the Function field. Setting the Event Flags field to all zeros in a "Reset Event Flags" request message allows the controller to obtain the current state of the Event Flags and the current Event Sequence Number of the port without changing the state of the Event Flags. The correspondence between the types of Event message and the bits of the Event Flags field is as follows: 0 1 2 3 4 5 6 7 +-+-+-+-+-+-+-+-+ |U|D|I|N|Z|x x x| +-+-+-+-+-+-+-+-+ U: Port Up Bit 0, (most significant bit) D: Port Down Bit 1, I: Invalid Label Bit 2, N: New Port Bit 3, Z: Dead Port Bit 4, x: Unused Bits 5--7. Duration Is the length of time, in seconds, that any of the loopback states remain in operation. When the duration has expired the port will automatically be returned to service. If another Port Management message is received for the same port before the duration has expired, the loopback will continue to remain in operation for the length of time specified by the Duration field in the new message. The Duration field is only used in request messages with the Function field set to Internal Loopback, External Loopback, or Bothway Loopback. Function Specifies the action to be taken. The specified action Worster, et. al. Page 35] Internet Draft General Switch Management Protocol Feb 1999 will be taken regardless of the current status of the port (Available, Unavailable, or any Loopback state). If the specified function requires a new Port Session Number to be generated, the new Port Session Number must be returned in the success response message. The defined values of the Function field are: Bring Up: Function = 1. Bring the port into service. All connections that arrive at the specified input port must be deleted and a new Port Session Number must be selected using some form of random number. On completion of the operation all dynamically assigned Label values for the specified input port must be unassigned, i.e. no connections will be established in the Label space that GSMP controls on this input port. The Port Status of the port afterwards will be Available. Take Down: Function = 2. Take the port out of service. Any cells received at this port will be discarded. No cells will be transmitted from this port. The Port Status of the port afterwards will be Unavailable. The behavior is undefined if the port is taken down over which the GSMP session that controls the switch is running. (In this case the most probable behavior would be for the switch either to ignore the message or to terminate the current GSMP session and to initiate another session, possibly with the backup controller, if any.) The correct method to reset the link over which GSMP is running is to issue an RSTACK message in the adjacency protocol. Internal Loopback: Function = 3. Cells arriving at the output port from the switch fabric are looped through to the input port to return to the switch fabric. All of the ATM functions of the input port above the physical layer, e.g. header translation, are performed upon the looped back cells. The Port Status of the port afterwards will be Internal Loopback. External Loopback: Function = 4. Cells arriving at the input port from the external communications link are immediately Worster, et. al. Page 36] Internet Draft General Switch Management Protocol Feb 1999 looped back to the communications link at the physical layer without entering the input port. None of the ATM functions of the input port above the physical layer are performed upon the looped back cells. The Port Status of the port afterwards will be External Loopback. Bothway Loopback: Function = 5. Both internal and external loopback are performed. The Port Status of the port afterwards will be Bothway Loopback. Reset Input Port: Function = 6. All connections that arrive at the specified input port must be deleted and the input and output port hardware re-initialized. On completion of the operation all dynamically assigned Label values for the specified input port must be unassigned, i.e. no connections will be established in the Label space that GSMP controls on this input port. The range of VPIs and VCIs that may be controlled by GSMP on this port will be set to the default values specified in the Port Configuration message. The transmit cell rate of the output port must be set to its default value. The Port Session Number is not changed by the Reset Input Port function. The Port Status of the port afterwards will be Unavailable. Reset Event Flags: Function = 7. For each bit that is set in the Event Flags field, the corresponding Event Flag in the switch port must be reset. The Port Status of the port is not changed by this function. Set Transmit Cell Rate: Function = 8. Sets the transmit cell rate of the output port as close as possible to the rate specified in the Transmit Cell Rate field. In the success response message the Transmit Cell Rate must indicate the actual transmit cell rate of the output port. If the transmit cell rate of the requested output port cannot be changed, a failure response must be returned with the Code field indicating: "The transmit cell rate of this output port cannot be changed." If the transmit cell rate of the requested output port can be changed, but the value of the Transmit Cell Rate field is beyond the range of acceptable values, a failure response Worster, et. al. Page 37] Internet Draft General Switch Management Protocol Feb 1999 must be returned with the Code field indicating: "Requested transmit cell rate out of range for this output port." In the failure response message the Transmit Cell Rate must contain the same value as contained in the request message that caused the failure. The transmit cell rate of the output port is not changed by the Bring Up, Take Down, or any of the Loopback functions. It is returned to the default value by the Reset Input Port function. Transmit Cell Rate This field is only used in request and success response messages with the Function field set to "Set Transmit Cell Rate." It is used to set the output cell rate of the output port. It is specified in cells/s. If the Transmit Cell Rate field contains the value 0xFFFFFFFF the transmit cell rate of the output port should be set to the highest valid value. 5.2 Label Range Message [Editor's note: this message is ATM specific. It needs to be decided if we need such flexibility for non ATM ports. If so, we could either generalise this message or add similar messages for non ATM ports.] The default label range, Min VPI to Max VPI and Min VCI to Max VCI, is specified for each port by the Port Configuration or the All Ports Configuration messages. When the protocol is initialized, before the transmission of any Label Range messages, the label range of each port will be set to the default label range. (The default label range is dependent upon the switch design and configuration and is not specified by the GSMP protocol.) The Label Range message allows the range of VPIs supported by a specified port, or the range of VCIs supported by a specified VPI on a specified port, to be changed. Each switch port must declare whether it supports the Label Range message in the Port Configuration or the All Ports Configuration messages. The Label Range message is: Message Type = 33 The Label Range message has the following format for the request and success response messages: Worster, et. al. Page 38] Internet Draft General Switch Management Protocol Feb 1999 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Session Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Q|V|x x| Min VPI |x x x x| Max VPI | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Min VCI | Max VCI | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remaining VPIs | Remaining VCIs | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Flags Q: Query If the Query flag is set in a request message, the switch must respond with the current range of valid VPIs, or the current range of valid VCIs on a specified VPI, according to the Label flag. The current label range is not changed by a request message with the Query flag set. If the Query flag is zero, the message is requesting a label change operation. V: Label If the Label flag is set, the message refers to a range of VPIs only. The Min VCI and Max VCI fields are unused. If the Label flag is zero the message refers to a range of VCIs on either one VPI or on a range of VPIs. x: Unused Min VPI Max VPI Specify a range of VPI values, Min VPI to Max VPI inclusive. A single VPI may be specified with a Min VPI and a Max VPI having the same value. In a request message, if the value of the Max VPI field is less than or equal to the value of the Min VPI field, the requested range is a single VPI with a value equal to the Min VPI field. Zero is a valid value. In a request message, if the Query flag is set, and the Label flag is zero, the Max VPI field specifies a single VPI and the Worster, et. al. Page 39] Internet Draft General Switch Management Protocol Feb 1999 Min VPI field is not used. The maximum valid value of these fields for both request and response messages is 0xFFF. Min VCI Max VCI Specify a range of VCI values, Min VCI to Max VCI inclusive. A single VCI may be specified with a Min VCI and a Max VCI having the same value. In a request message, if the value of the Max VCI field is less than or equal to the value of the Min VCI field, the requested range is a single VCI with a value equal to the Min VCI field. Zero is a valid value. (However, VPI=0, VCI=0 is not available as a virtual channel connection as it is used as a special value in ATM to indicate an unassigned cell.) Remaining VPIs Remaining VCIs These fields are unused in the request message. In the success response message and in the failure response message these fields give the maximum number of remaining VPIs and VCIs that could be requested for allocation on the specified port (after completion of the requested operation in the case of the success response). It gives the switch controller an idea of how many VPIs and VCIs it could request. The number given is the maximum possible given the constraints of the switch hardware. There is no implication that this number of VPIs and VCIs is available to every switch port. If the Query flag and the Label flag are set in the request message, the switch must reply with a success response message containing the current range of valid VPIs that are supported by the port. The Min VPI and Max VPI fields are not used in the request message. If the Query flag is set and the Label flag is zero in the request message, the switch must reply with a success response message containing the current range of valid VCIs that are supported by the VPI specified by the Max VPI field. If the requested VPI is invalid, a failure response must be returned indicating: "One or more of the specified input VPIs is invalid." The Min VPI field is not used in either the request or success response messages. If the Query flag is zero and the Label flag is set in the request message, the Min VPI and Max VPI fields specify the new range of VPIs to be allocated to the input port specified by the Port Worster, et. al. Page 40] Internet Draft General Switch Management Protocol Feb 1999 field. Whatever the range of VPIs previously allocated to this port it should be increased or decreased to the specified value. If the Query flag and the Label flag are zero in the request message, the Min VCI and Max VCI fields specify the range of VCIs to be allocated to each of the VPIs specified by the VPI range. Whatever the range of VCIs previously allocated to each of the VPIs within the specified VPI range on this port, it should be increased or decreased to the specified value. The allocated VCI range must be the same on each of the VPIs within the specified VPI range. The success response to a Label Range message requesting a change of label range is a copy of the request message with the Remaining VPIs and Remaining VCIs fields updated to the new values after the Label Range operation. If the switch is unable to satisfy a request to change the VPI range, it must return a failure response message with the Code field set to "Cannot support requested VPI range." In this failure response message the switch must use the Min VPI and Max VPI fields to suggest a VPI range that it would be able to satisfy. If the switch is unable to satisfy a request to change the VCI range on all VPIs within the requested VPI range, it must return a failure response message with the Code field set to "Cannot support requested VCI range on all requested VPIs." In this failure response message the switch must use the Min VPI, Max VPI, Min VCI, and Max VCI fields to suggest a VPI and VCI range that it would be able to satisfy. In all other failure response messages for the label range operation the switch must return the values of Min VPI, Max VPI, Min VCI, and Max VCI from the request message. While switches can typically support all 256 or 4096 VPIs the VCI range that can be supported is often more constrained. Often the Min VCI must be 0 or 32. Typically all VCIs within a particular VPI must be contiguous. The hint in the failure response message allows the switch to suggest a label range that it could satisfy in view of its particular architecture. While the Label Range message is defined to specify both a range of VPIs and a range of VCIs within each VPI, the most likely use is to change either the VPI range or the range of VCIs within a single VPI. It is possible for a VPI to be valid but to be allocated no valid VCIs. Such a VPI could be used for a virtual path connection but to support virtual channel connections it would need to be allocated a range of VCIs. Worster, et. al. Page 41] Internet Draft General Switch Management Protocol Feb 1999 A Label Range request message may be issued regardless of the Port Status or the Line Status of the target switch port. If the Port field of the request message contains an invalid port (a port that does not exist or a port that has been removed from the switch) a failure response message must be returned with the Code field set to, "One or more of the specified ports does not exist." 6. State and Statistics Messages The state and statistics messages permit the controller to request the values of various hardware counters associated with the switch input and output ports and connections. They also permit the controller to request the connection state of a switch input port. The Connection Activity message is used to determine whether one or more specific connections have recently been carrying traffic. The Statistics message is used to query the various port and connection traffic and error counters. The Report Connection State message is used to request an input port to report the connection state for a single connection, a single ATM virtual path connection, or for the entire input port. 6.1 Connection Activity Message The Connection Activity message is used to determine whether one or more specific connections have recently been carrying traffic. The Connection Activity message contains one or more Activity Records. Each Activity Record is used to request and return activity information concerning a single connection. Each connection is specified by its input port and Input Label which are specified in the Input Port and Input Label fields of each Activity Record. Two forms of activity detection are supported. If the switch supports per connection traffic accounting, the current value of the traffic counter for each specified connection must be returned. The units of traffic counted are not specified but will typically be either cells or frames. The controller must compare the traffic counts returned in the message with previous values for each of the specified connections to determine whether each connection has been active in the intervening period. If the switch does not support per connection traffic accounting, but is capable of detecting per connection activity by some other unspecified means, the result may be indicated for each connection using the Flags field. The Connection Activity message is: Message Type = 48 Worster, et. al. Page 42] Internet Draft General Switch Management Protocol Feb 1999 The Connection Activity request and success response messages have the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Number of Records | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Activity Records ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Number of Records Field specifies the number of Activity Records to follow. The number of Activity records in a single Connection Activity message must not cause the packet length to exceed the maximum transmission unit defined by the encapsulation. Each Activity Record has the following format: +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Input Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |V|C|A|E| | +-+-+-+-+ Input Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Traffic Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Input Port Identifies the port number of the input port on which the connection of interest arrives in order to identify the connection (regardless of whether the traffic count for the connection is maintained on the input port or the output port). Input Label Fields identify the specific connection for which statistics are being requested. Flags Worster, et. al. Page 43] Internet Draft General Switch Management Protocol Feb 1999 V: Valid Record In the success response message the Valid Record flag is used to indicate an invalid Activity Record. The flag must be zero if any of the fields in this Activity Record are invalid, if the input port specified by the Input Port field does not exist, or if the specified connection does not exist. If the Valid Record flag is zero in a success response message, the Counter flag, the Activity flag, and the Traffic Count field are undefined. If the Valid Record flag is set, the Activity Record is valid, and the Counter and Activity flags are valid. The Valid Record flag is not used in the request message. C: Counter In a success response message, if the Valid Record flag is set, the Counter flag, if zero, indicates that the value in the Traffic Count field is valid. If set, it indicates that the value in the Activity flag is valid. The Counter flag is not used in the request message. A: Activity In a success response message, if the Valid Record and Counter flags are set, the Activity flag, if set, indicates that there has been some activity on this connection since the last Connection Activity message for this connection. If zero, it indicates that there has been no activity on this connection since the last Connection Activity message for this connection. The Activity flag is not used in the request message. E: Extension Label The Extension Label flag if zero indicates that the Input Label field is a 28 bit field. If the Extension Label flag is set then the Input Label field is a 60 bit field structured as a 28 bit first level label field followed by a 32 bit second level label field. Traffic Count Field is not used in the request message. In the success response message, if the switch supports per connection traffic counting, the Traffic Count field must be set to the value of a free running, connection specific, 64-bit traffic counter counting traffic flowing across the specified connection. The value of the traffic counter is not modified by reading it. If per connection traffic counting is supported, the switch must report the Connection Activity result using the traffic count rather than using the Activity flag. Worster, et. al. Page 44] Internet Draft General Switch Management Protocol Feb 1999 The format of the failure response is the same as the request message with the Number of Records field set to zero and no Connection Activity records returned in the message. If the switch is incapable of detecting per connection activity, a failure response must be returned indicating, "The specified request is not implemented on this switch." 6.2 Statistics Messages The Statistics messages are used to query the various port and connection and error counters. The Statistics request messages have the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |x x x|E| | +-+-+-+-+ Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ E: Extension Label The Extension Label flag if zero indicates that the Label field is a 28 bit field. If the Extension Label flag is set then the Label field is a 60 bit field structured as a 28 bit first level label field followed by a 32 bit second level label field. Label The Label Field identifies the specific connection for which statistics are being requested. The success response for the Statistics message has the following format: Worster, et. al. Page 45] Internet Draft General Switch Management Protocol Feb 1999 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |x x x|E| | +-+-+-+-+ Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Input Cell Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Input Frame Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Input Cell Discard Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Input Frame Discard Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + ATM HEC Error Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Input Invalid Label Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Output Cell Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Output Frame Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Output Cell Discard Count + | | Worster, et. al. Page 46] Internet Draft General Switch Management Protocol Feb 1999 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Output Frame Discard Count + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ EPort Label Fields are the same as those of the request message. Input Cell Count Output Cell Count Give the value of a free running 64-bit counter counting cells arriving at the input or departing from the output respectively. Input Frame Count Output Frame Count Give the value of a free running 64-bit counter counting frames (packets) arriving at the input or departing from the output respectively. Input Cell Discard Count Output Cell Discard Count Give the value of a free running 64-bit counter counting cells discarded due to queue overflow on an input port or on an output port respectively. Input Frame Discard Count Output Frame Discard Count Give the value of a free running 64-bit counter counting frames discarded due to congestion on an input port or on an output port respectively. ATM HEC Error Count Gives the value of a free running 64-bit counter counting ATM cells discarded due to header checksum errors on arrival at an input port. Invalid Label Count Gives the value of a free running 64-bit counter counting cells or frames discarded because their Label is invalid on arrival at an input port. Worster, et. al. Page 47] Internet Draft General Switch Management Protocol Feb 1999 6.2.1 Port Statistics Message The Port Statistics message requests the statistics for the switch port specified in the Port field. The contents of the Label field in the Port Statistics request message is ignored. All of the count fields in the success response message refer to per-port counts regardless of the connection to which the cells or frames belong. Any of the count fields in the success response message not supported by the port must be set to zero. The Port Statistics message is: Message Type = 49 6.2.2 Connection Statistics Message The Connection Statistics message requests the statistics for the connection specified in the Label field that arrives on the switch input port specified in the Port field. All of the count fields in the success response message refer only to the specified connection. The ATM HEC Error Count and Invalid Label Count fields are not connection specific and must be set to zero. Any of the other count fields not supported on a per connection basis must be set to zero in the success response message. The Connection Statistics message is: Message Type = 50 6.2.3 QoS Class Statistics Message The QoS Class Statistics message is not supported in this version of GSMP. Message Type = 51 is reserved. 6.3 Report Connection State Message The Report Connection State message is used to request an input port to report the connection state for a single connection, a single ATM virtual path connection, or for the entire input port. The Report Connection State message is: Message Type = 52 The Report Connection State request message has the following format: Worster, et. al. Page 48] Internet Draft General Switch Management Protocol Feb 1999 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Input Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A|V|x|E| | +-+-+-+-+ Input Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Input PortIdentifies the port number of the input port for which the connection state is being requested. Flags A: All Connections If the All Connections flag is set, the message requests the connection state for all connections that arrive at the input port specified by the Input Port field. In this case the Input Label field and the Label flag are unused. V: ATM VPI The ATM VPI flag may only be set for ports with PortType=ATM. If the switch recieves a Report Connection State message in which the ATM VPI flag set and in which the input port specified by the Input Port field does not have PortType=ATM, the switch must return an Error Message "xxxxxx". If the All Connections flag is zero and the ATM VPI flag is also zero, the message requests the connection state for the connection that arrives at the input port specified by the Port and Input Label fields. ATM specific procedures: If the All Connections flag is zero and the ATM VPI flag is set and the input port specified by the Input Port field has LabelType=ATM, the message requests the connection state for the virtual path connection that arrives at the input port specified by the Input Port and Input VPI fields. If the specified Input VPI Worster, et. al. Page 49] Internet Draft General Switch Management Protocol Feb 1999 identifies an ATM virtual path connection (i.e. a single switched virtual path) the state for that connection is requested. If the specified Input VPI identifies a virtual path containing virtual channel connections, the message requests the connection state for all virtual channel connections that belong to the specified virtual path. x: Unused. E: Extension Label The Extension Label flag if zero indicates that the Input Label field is a 28 bit field. If the Extension Label flag is set then the Input Label field is a 60 bit field structured as a 28 bit first level label field followed by a 32 bit second level label field. Input Label Field identifies the specific connection for which connection state is being requested. For a virtual path connection (switched as a single virtual path connection) or a virtual path (switched as one or more virtual channel connections within the virtual path) the Input VCI field is not used. For requests that do not require a virtual path connection or virtual channel connection to be specified, the Input VPI and Input VCI fields are not used. The Report Connection State success response message has the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Input Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Connection Records ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Input PortIs the same as the Input Port field in the request Worster, et. al. Page 50] Internet Draft General Switch Management Protocol Feb 1999 message. It identifies the port number of the input port for which the connection state is being reported. Sequence Number In the case that the requested connection state cannot be reported in a single success response message, each successive success response message in reply to the same request message must increment the Sequence Number. The Sequence Number of the first success response message, in response to a new request message, must be zero. Connection Records Each success response message must contain one or more Connection Records. Each Connection Record specifies a single point-to-point or point-to-multipoint connection. The number of Connection Records in a single Report Connection State success response must not cause the packet length to exceed the maximum transmission unit defined by the encapsulation. If the requested connection state cannot be reported in a single success response message, multiple success response messages must be sent. All success response messages that are sent in response to the same request message must have the same Input Port and Transaction Identifier fields as the request message. A single Connection Record must not be split across multiple success response messages. The More flag of the last Connection Record in a success response message indicates whether the response to the request has been completed or whether one or more further success response messages should be expected in response to the same request message. Each Connection Record has the following format: +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A|V|P|M| Input VPI | Input VCI | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Output Branch Records ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ [Editor's note: help, where do i put the extension label flag?] Flags A: All Connections V: ATM VPI For the first Connection Record in each success response Worster, et. al. Page 51] Internet Draft General Switch Management Protocol Feb 1999 message the All Connections and the ATM VPI flags must be the same as those of the request message. For successive Connection Records in the same success response message these flags are not used. P: ATM VPC The ATM VPC flag, if set and only if set, indicates that the Connection Record refers to an ATM virtual path connection. M: More If the More flag is set, it indicates that another Connection Record, in response to the same request message, will follow either in the same success response message or in a successive success response message. If the More flag is zero it indicates that this is the last Connection record in this success response message and that no further success response messages will be sent in response to the current request message. It indicates that the response to the request message is now complete. Input Label The input label of the connection specified in this Connection Record. If this Connection Record specifies a virtual path connection (the VPC flag is set) the Input VCI field is unused. Output Branch Records Each Connection Record must contain one or more Output Branch Records. Each Output Branch Record specifies a single output branch belonging to the connection identified by the Input Label field of the Connection Record and the Input Port field of the Report Connection State message. A point-to-point connection will require only a single Output Branch Record. A point-to- multipoint connection will require multiple Output Branch Records. The last Output Branch Record of each Connection Record is indicated by the Last Branch flag of the Output Branch Record. If a point-to-multipoint connection has more output branches than can fit in a single Connection Record contained within a single success response message, that connection may be reported using multiple Connection Records in multiple success response messages. Each Output Branch Record has the following format: Worster, et. al. Page 52] Internet Draft General Switch Management Protocol Feb 1999 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Output Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |L|x x|E| | +-+-+-+-+ Output Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Output PortThe output port of the switch to which this output branch is routed. Flags L: Last Branch The Last Branch flag, if set, indicates that this is the last Output Branch Record of this Connection Record. If zero, it indicates that one or more further Output Branch Records are to follow. If this is the last Output Branch Record in the message and the Last Branch flag is zero, further output branches belonging to the same connection will be given in another Connection Record. This Connection Record will be the first Connection Record in the next success response message. This Connection Record must have the same Input VPI and Input VCI values as the current Connection Record. E: Extension Label The Extension Label flag if zero indicates that the Output Label field is a 28 bit field. If the Extension Label flag is set then the Input Label field is a 60 bit field structured as a 28 bit first level label field followed by a 32 bit second level label field. x: Unused. Output Label The output label of the output branch specified in this Output Branch Record. ATM specific procedures: If this Output Branch Record is part of a Connection Record that specifies a virtual path connection (the ATM VPC flag is set) the Output VCI field is unused. Worster, et. al. Page 53] Internet Draft General Switch Management Protocol Feb 1999 A Report Connection State request message may be issued regardless of the Port Status or the Line Status of the target switch port. If the Input Port of the request message is valid, and the All Connections flag is set, but there are no connections established on that port, a failure response message must be returned with the code field set to, "Failure specific to the particular message type." For the Report Connection State message, this failure code indicates that no connections matching the request message were found. This failure message should also be returned if the Input Port of the request message is valid, the All Connections flag is zero, and no connections are found on that port matching the specified virtual path connection, virtual path, or virtual channel connection. 7. Configuration Messages The configuration messages permit the controller to discover the capabilities of the switch. Three configuration request messages have been defined: Switch, Port, and All Ports. All configuration request messages have the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 7.1 Switch Configuration Message The Switch Configuration message requests the global (non port- specific) configuration for the switch. The Switch Configuration message is: Message Type = 64 The Port field is not used in the request message. The Switch Configuration success response message has the following format: Worster, et. al. Page 54] Internet Draft General Switch Management Protocol Feb 1999 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Firmware Version Number | Window Size | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Switch Type | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Switch Name | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Firmware Version Number The version number of the switch control firmware installed. Window Size The maximum number of unacknowledged request messages that may be transmitted by the controller without the possibility of loss. This field is used to prevent request messages being lost in the switch because of overflow in the receive buffer. The field is a hint to the controller. If desired, the controller may experiment with higher and lower window sizes to determine heuristically the best window size. [editor's note: some text may be added here with regard to the tcp/ip encapsulation since if tcp is used then the switch may adjust the reciever window size.] Switch Type A 16-bit field allocated by the manufacturer of the switch. (For these purposes the manufacturer of the switch is assumed to be the organization identified by the OUI in the Switch Name field.) The Switch Type identifies the product. When the Switch Type is combined with the OUI from the Switch Name the product is uniquely identified. Network Management may use this identification to obtain product related information from a database. Switch Name A 48-bit quantity that is unique within the operational context of the device. A 48-bit IEEE 802 MAC address, if available, may be used as the Switch Name. The most significant 24 bits of the Switch Name must be an Worster, et. al. Page 55] Internet Draft General Switch Management Protocol Feb 1999 Organizationally Unique Identifier (OUI) that identifies the manufacturer of the switch. 7.2 Port Configuration Message The Port Configuration message requests the switch for the configuration information of a single switch port. The Port field in the request message specifies the port for which the configuration is requested. The Port Configuration message is: Message Type = 65. The Port Configuration success response message has the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Session Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PortType |S|x x x x x x x| Data Fields Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ PortType Specific Data ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Service Model Data ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Port The switch port to which the configuration information refers. Configuration information relating to both the input and the output sides of the switch port is given. Port numbers are 32 bits wide and allocated by the switch. The switch may choose to structure the 32 bits into subfields that have meaning to the physical structure of the switch hardware (e.g. physical slot and port). This structure may be indicated in the Physical Slot Number and Physical Port Number fields. Worster, et. al. Page 56] Internet Draft General Switch Management Protocol Feb 1999 PortType [Editor's note: words to be written. also, somewhere in chapter 1 or so we will need text that explains that certain protocol elements depend on the PortType value.] PortType = 0d01 = ATM S: Service Model If set, indicates that service model data follows the PortSpecific port configuration data. Data Fields Length The total length in bytes of the combined PortType Specific Data and Service Model Data fields. The length of each of these fields may be derived from the other data so the value of Data Fields Length serves primarily as a check and to assist parsing of the All Ports Configuration message success response. PortType Specific Data This field contains the configuration data specific to the particular port type as specified by the PortType field. The field format and length depends also on the value of PortType. PortType Specific Data is defined below. Service Model Data This field contains data that describes the services within the Service Model that can be supported by the port. The length of this field is variable. [Editor's note: beyond the above sentences no definition of the service model has been provided in this revision of the draft. this will be extended in future revisions.] 7.2.1 PortType Specific Data The length, format and semantics of the PortType Specific Data field in the Port Configuration message suffess response and in the Port Records of the All Port Configuration message success response all depend on the PortType value of the same message or record respectively. The specification of the PortType Specific Data field for each defined PortType value are given in the subsequent subsections. Worster, et. al. Page 57] Internet Draft General Switch Management Protocol Feb 1999 7.2.1.1 PortType Specific Data for PortType=ATM 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |V|M|L|R| Min VPI |Q|x x x| Max VPI | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Min VCI | Max VCI | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Receive Cell Rate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transmit Cell Rate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Status | Line Type | Line Status | Priorities | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Physical Slot Number | Physical Port Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Flags V: VP Switching The VP Switching flag, if set, indicates that this input port is capable of supporting virtual path switching. Else, if zero, it indicates that this input port is only capable of virtual channel switching. M: Multicast Labels The Multicast Labels flag, if set, indicates that this output port is capable of labelling each output branch of a point-to-multipoint tree with a different label. If zero, it indicates that this output port is not able to label each output branch of a point-to-multipoint tree with a different label. L: Logical Multicast The Logical Multicast flag, if set, indicates that this output port is capable of supporting more than a single branch from any point-to-multipoint connection. This capability is often referred to as logical multicast. If zero, it indicates that this output port can only support a single output branch from each point-to- multipoint connection. R: Label Range The Label Range flag, if set, indicates that this switch port is capable of reallocating its VPI label range or its VCI label range and therefore accepts the Label Worster, et. al. Page 58] Internet Draft General Switch Management Protocol Feb 1999 Range message. Else, if zero, it indicates that this port does not accept Label Range messages. Q: QoS The QoS flag, if set, indicates that this switch port is capable of handling the Quality of Service messages defined in section 9 of this specification. Else, if zero, it indicates that this port does not accept the Quality of Service messages. x: Unused Min VPI The default minimum value of dynamically assigned incoming VPI that the connection table on the input port supports and that may be controlled by GSMP. This value is not changed as a result of the Label Range message. Max VPI The default maximum value of dynamically assigned incoming VPI that the connection table on the input port supports and that may be controlled by GSMP. This value is not changed as a result of the Label Range message. At power-on, after a hardware reset, and after the Reset Input Port function of the Port Management message, the input port must handle all values of VPI within the range Min VPI to Max VPI inclusive and GSMP must be able to control all values within this range. It should be noted that the range Min VPI to Max VPI refers only to the incoming VPI range that can be supported by the associated port. No restriction is placed on the values of outgoing VPIs that may be written into the cell header. If the switch does not support virtual paths it is acceptable for both Min VPI and Max VPI to specify the same value, most likely zero. Use of the Label Range message allows the range of VPIs supported by the port to be changed. However, the Min VPI and Max VPI fields in the Port Configuration and All Ports Configuration messages always report the same default values regardless of the operation of the Label Range message. Min VCI The default minimum value of dynamically assigned incoming VCI that the connection table on the input port Worster, et. al. Page 59] Internet Draft General Switch Management Protocol Feb 1999 can support and may be controlled by GSMP. This value is not changed as a result of the Label Range message. Max VCI The default maximum value of dynamically assigned incoming VCI that the connection table on the input port can support and may be controlled by GSMP. This value is not changed as a result of the Label Range message. At power-on, after a hardware reset, and after the Reset Input Port function of the Port Management message, the input port must handle all values of VCI within the range Min VCI to Max VCI inclusive, for each of the virtual paths in the range Min VPI to Max VPI inclusive, and GSMP must be able to control all values within this range. It should be noted that the range Min VCI to Max VCI refers only to the incoming VCI range that can be supported by the associated port on each of the virtual paths in the range Min VPI to Max VPI. No restriction is placed on the values of outgoing VCIs that may be written into the cell header. Use of the Label Range message allows the range of VCIs to be changed on each VPI supported by the port. However, the Min VCI and Max VCI fields in the Port Configuration and All Ports Configuration messages always report the same default values regardless of the operation of the Label Range message. For a port over which the GSMP protocol is operating, the VCI of the GSMP control channel may or may not be reported as lying within the range Min VCI to Max VCI. A switch should honor a connection request message that specifies the VCI value of the GSMP control channel even if it lies outside the range Min VCI to Max VCI. Receive Cell Rate The maximum rate of cells that may arrive at the input port in cells/s. Transmit Cell Rate The maximum rate of cells that may depart from the output port in cells/s. (The transmit cell rate of the output port may be changed by the Set Transmit Cell Rate function of the Port Management message.) Port Status Gives the administrative state of the port. The defined values of the Port Status field are: Worster, et. al. Page 60] Internet Draft General Switch Management Protocol Feb 1999 Available: Port Status = 1. The port is available to both send and receive cells. When a port changes to the Available state from any other administrative state, all dynamically assigned connections must be cleared and a new Port Session Number must be generated. Unavailable: Port Status = 2. The port has intentionally been taken out of service. No cells will be transmitted from this port. No cells will be received by this port. Internal Loopback: Port Status = 3. The port has intentionally been taken out of service and is in internal loopback: cells arriving at the output port from the switch fabric are looped through to the input port to return to the switch fabric. All of the ATM functions of the input port above the physical layer, e.g. header translation, are performed upon the looped back cells. External Loopback: Port Status = 4. The port has intentionally been taken out of service and is in external loopback: cells arriving at the input port from the external communications link are immediately looped back to the communications link at the physical layer without entering the input port. None of the ATM functions of the input port above the physical layer are performed upon the looped back cells. Bothway Loopback: Port Status = 5. The port has intentionally been taken out of service and is in both internal and external loopback. The Port Status of the port over which the GSMP session controlling the switch is running, must be declared Available. The controller will ignore any other Port status for this port. The Port Status of switch ports after power-on initialization is not defined by GSMP. Line Type The type of physical transmission interface for this port. The values for this field are defined by the Worster, et. al. Page 61] Internet Draft General Switch Management Protocol Feb 1999 atmIfType object specified in the Ipsilon IP Switch MIB [4]. Line Status The status of the physical transmission medium connected to the port. The defined values of the Line Status field are: Up: Line Status = 1. The line is able to both send and receive cells. When the Line Status changes to Up from either the Down or Test states, a new Port Session Number must be generated. Down:Line Status = 2. The line is unable either to send or receive cells or both. Test:Line Status = 3. The port or line is in a test mode, for example, power-on test. PrioritiesThe number of different priority levels that this output port can assign to connections. Zero is invalid in this field. If an output port is able to support "Q" priorities, the highest priority is numbered zero and the lowest priority is numbered "Q-1". The ability to offer different qualities of service to different connections based upon their priority is assumed to be a property of the output port of the switch. It may be assumed that for connections that share the same output port, an ATM cell on a connection with a higher priority is much more likely to exit the switch before an ATM cell on a connection with a lower priority if they are both in the switch at the same time. Physical Slot Number The physical location of the slot in which the port is located. It is an unsigned 16-bit integer that can take any value except 0xFFFF. The value 0xFFFF is used to indicate "unknown." The Physical Slot Number is not used by the GSMP protocol. It is provided to assist network management in functions such as logging, port naming, and graphical representation. Physical Port Number The physical location of the port within the slot in which the port is located. It is an unsigned 16-bit Worster, et. al. Page 62] Internet Draft General Switch Management Protocol Feb 1999 integer that can take any value except 0xFFFF. The value 0xFFFF is used to indicate "unknown." The Physical Port Number is not used by the GSMP protocol. It is provided to assist network management in functions such as logging, port naming, and graphical representation. There must be a one to one mapping between Port Number and the Physical Slot Number and Physical Port Number combination. Two different Port Numbers must not yield the same Physical Slot Number and Physical Port Number combination. The same Port Number must yield the same Physical Slot Number and Physical Port Number within a single GSMP session. If both Physical Slot Number and Physical Port Number indicate "unknown" the physical location of switch ports may be discovered by looking up the product identity in a database to reveal the physical interpretation of the 32-bit Port Number. 7.3 All Ports Configuration Message The All Ports Configuration message requests the switch for the configuration information of all of its ports. The All Ports Configuration message is: Message Type = 66 The Port field is not used in the request message. The All Ports Configuration success response message has the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Number of Records | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Port Records ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Number of Records Field gives the total number of Port Records to be returned in response to the All Ports Configuration request message. The number of port records in a single Worster, et. al. Page 63] Internet Draft General Switch Management Protocol Feb 1999 All Ports Configuration success response must not cause the packet length to exceed the maximum transmission unit defined by the encapsulation. If a switch has more ports than can be sent in a single success response message it must send multiple success response messages. All success response messages that are sent in response to the same request message must have the same Transaction Identifier as the request message and the same value in the Number of Records field. All success response messages that are sent in response to the same request message, except for the last message, must have the result field set to "More." The last message, or a single success response message, must have the result field set to "Success." All Port records within a success response message must be complete, i.e. a single Port record must not be split across multiple success response messages. Port Records Follow in the remainder of the message. Each port record has the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Session Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PortType |S|x x x x x x x| Data Fields Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ PortType Specific Data ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Service Model Data ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The definition of the fields in the Port Record is exactly the same as that of the Port Configuration message. 8. Event Messages Event messages allow the switch to inform the controller of certain asynchronous events. Event messages are not acknowledged. The Result field and the Code field in the message header are not Worster, et. al. Page 64] Internet Draft General Switch Management Protocol Feb 1999 used and should be set to zero. Event messages are not sent during initialization. Event messages have the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Result | Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transaction Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Port Session Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Event Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |x x x|E| | +-+-+-+-+ Label ~ ~ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Event Sequence Number The current value of the Event Sequence Number for the specified port. The Event Sequence Number is set to zero when the port is initialized. It is incremented by one each time the port detects an asynchronous event that the switch would normally report via an Event message. The Event Sequence Number must be incremented each time an event occurs even if the switch is prevented from sending an Event message due to the action of the flow control. E: Extension Label The Extension Label flag if zero indicates that the Label field is a 28 bit field. If the Extension Label flag is set then the Label field is a 60 bit field structured as a 28 bit first level label field followed by a 32 bit second level label field. Label Field gives the Label to which the event message refers. If this field is not required by the event message it is set to zero. Each switch port must maintain an Event Sequence Number and a set of Event Flags, one Event Flag for each type of Event message. When a switch port sends an Event message it must set the Event Flag on that port corresponding to the type of the event. The port is not permitted to send another Event message of the same type Worster, et. al. Page 65] Internet Draft General Switch Management Protocol Feb 1999 until the Event Flag has been reset. Event Flags are reset by the "Reset Event Flags" function of the Port Management message. This is a simple flow control preventing the switch from flooding the controller with event messages. The Event Sequence Number of the port must be incremented every time an event is detected on that port even if the port is prevented from reporting the event due to the action of the flow control. This allows the controller to detect that it has not been informed of some events that have occurred on the port due to the action of the flow control. 8.1 Port Up Message The Port Up message informs the controller that the Line Status of a port has changed from either the Down or Test state to the Up state. When the Line Status of a switch port changes to the Up state from either the Down or Test state a new Port Session Number must be generated, preferably using some form of random number. The new Port Session Number is given in the Port Session Number field. The Label field is not used and is set to zero. The Port Up message is: Message Type = 80 8.2 Port Down Message The Port Down message informs the controller that the Line Status of a port has changed from the Up state to the Down state. This message will be sent to report link failure if the switch is capable of detecting link failure. The port session number that was valid before the port went down is reported in the Port Session Number field. The Label field is not used and is set to zero. The Port Down message is: Message Type = 81 8.3 Invalid Label Message The Invalid Label message is sent to inform the controller that one or more cells or frames have arrived at an input port with a Label that is currently not allocated to an assigned connection. The input port is indicated in the Port field, and the Label in the Label field. The Invalid Label message is: Message Type = 82 8.4 New Port Message The New Port message informs the controller that a new port has been added to the switch. The port number of the new port is given Worster, et. al. Page 66] Internet Draft General Switch Management Protocol Feb 1999 in the Port field. A new Port Session Number must be assigned, preferably using some form of random number. The new Port Session Number is given in the Port Session Number field. The state of the new port is undefined so the Label field is not used and is set to zero. The New Port message is: Message Type = 83 8.5 Dead Port Message The Dead Port message informs the controller that a port has been removed from the switch. The port number of the port is given in the Port field. The Port Session Number that was valid before the port was removed is reported in the Port Session Number field. The Label fields are not used and are set to zero. The Dead Port message is: Message Type = 84 9. Service Model Definition 10. Adjacency Protocol The adjacency protocol is used to synchronize state across the link, to agree on which version of the protocol to use, to discover the identity of the entity at the other end of a link, and to detect when it changes. GSMP is a hard state protocol. It is therefore important to detect loss of contact between switch and controller, and to detect any change of identity of switch or controller. No GSMP messages other than those of the adjacency protocol may be sent across the link until the adjacency protocol has achieved synchronization. 10.1 Packet Format All GSMP messages belonging to the adjacency protocol have the following structure: Worster, et. al. Page 67] Internet Draft General Switch Management Protocol Feb 1999 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Timer |M| Code | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sender Name | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Receiver Name | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sender Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Receiver Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sender Instance | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Receiver Instance | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Version In the adjacency protocol the Version field is used for version negotiation. In a SYN message the Version field always contains the highest version understood by the sender. A receiver receiving a SYN message with a version higher than understood will ignore that message. A receiver receiving a SYN message with a version lower than its own highest version, but a version that it understands, will reply with a SYNACK with the version from the received SYN in its GSMP Version field. This defines the version of the GSMP protocol to be used while the adjacency protocol remains synchronized. All other messages will use the agreed version in the Version field. The version number for the version of the GSMP protocol defined by this specification is Version = 2. Message Type The adjacency protocol is: Message Type = 10 Timer The Timer field is used to inform the receiver of the timer value used in the adjacency protocol of the sender. The timer specifies the nominal time between Worster, et. al. Page 68] Internet Draft General Switch Management Protocol Feb 1999 periodic adjacency protocol messages. It is a constant for the duration of a GSMP session. The timer field is specified in units of 100ms. M-Flag The M-Flag is used in the SYN message to indicate whether the sender is a master or a slave. If the M-Flag is set in the SYN message, the sender is a master. If zero, the sender is a slave. The GSMP protocol is asymmetric, the controller being the master and the switch being the slave. The M-Flag prevents a master from synchronizing with another master, or a slave with another slave. If a slave receives a SYN message with a zero M-Flag, it must ignore that SYN message. If a master receives a SYN message with the M-Flag set, it must ignore that SYN message. In all other messages the M-Flag is not used. Code Field specifies the function of the message. Four Codes are defined for the adjacency protocol: SYN: Code = 1 SYNACK: Code = 2 ACK: Code = 3 RSTACK: Code = 4. Sender Name For the SYN, SYNACK, and ACK messages, is the name of the entity sending the message. The Sender Name is a 48- bit quantity that is unique within the operational context of the device. A 48-bit IEEE 802 MAC address, if available, may be used for the Sender Name. If the Ethernet encapsulation is used the Sender Name must be the Source Address from the MAC header. For the RSTACK message, the Sender Name field is set to the value of the Receiver Name field from the incoming message that caused the RSTACK message to be generated. Receiver Name For the SYN, SYNACK, and ACK messages, is the name of the entity that the sender of the message believes is at the far end of the link. If the sender of the message does not know the name of the entity at the far end of the link, this field should be set to zero. For the RSTACK message, he Receiver Name field is set to the value of the Sender Name field from the incoming message that caused the RSTACK message to be generated. Worster, et. al. Page 69] Internet Draft General Switch Management Protocol Feb 1999 Sender Port For the SYN, SYNACK, and ACK messages, is the local port number of the link across which the message is being sent. For the RSTACK message, the Sender Port field is set to the value of the Receiver Port field from the incoming message that caused the RSTACK message to be generated. Receiver Port For the SYN, SYNACK, and ACK messages, is what the sender believes is the local port number for the link, allocated by the entity at the far end of the link. If the sender of the message does not know the port number at the far end of the link, this field should be set to zero. For the RSTACK message, the Receiver Port field is set to the value of the Sender Port field from the incoming message that caused the RSTACK message to be generated. Sender Instance For the SYN, SYNACK, and ACK messages, is the sender's instance number for the link. It is used to detect when the link comes back up after going down or when the identity of the entity at the other end of the link changes. The instance number is a 32-bit number that is guaranteed to be unique within the recent past and to change when the link or node comes back up after going down. Zero is not a valid instance number. For the RSTACK message, the Sender Instance field is set to the value of the Receiver Instance field from the incoming message that caused the RSTACK message to be generated. Receiver Instance For the SYN, SYNACK, and ACK messages, is what the sender believes is the current instance number for the link, allocated by the entity at the far end of the link. If the sender of the message does not know the current instance number at the far end of the link, this field should be set to zero. For the RSTACK message, the Receiver Instance field is set to the value of the Sender Instance field from the incoming message that caused the RSTACK message to be generated. 10.2 Procedure The adjacency protocol is described by the following rules and state tables. The rules and state tables use the following operations: Worster, et. al. Page 70] Internet Draft General Switch Management Protocol Feb 1999 o The "Update Peer Verifier" operation is defined as storing the values of the Sender Instance, Sender Port, and Sender Name fields from a SYN or SYNACK message received from the entity at the far end of the link. o The procedure "Reset the link" is defined as: 1. Generate a new instance number for the link 2. Delete the peer verifier (set to zero the values of Sender Instance, Sender Port, and Sender Name previously stored by the Update Peer Verifier operation) 3. Send a SYN message 4. Enter the SYNSENT state. o The state tables use the following Boolean terms and operators: A The Sender Instance in the incoming message matches the value stored from a previous message by the "Update Peer Verifier" operation. B The Sender Instance, Sender Port, and Sender Name fields in the incoming message match the values stored from a previous message by the "Update Peer Verifier" operation. C The Receiver Instance, Receiver Port, and Receiver Name fields in the incoming message match the values of the Sender Instance, Sender Port, and Sender Name currently sent in outgoing SYN, SYNACK, and ACK messages. "&&" Represents the logical AND operation "||" Represents the logical OR operation "!" Represents the logical negation (NOT) operation. o A timer is required for the periodic generation of SYN, SYNACK, and ACK messages. The value of the timer is announced in the Timer field. The period of the timer is unspecified but a value of one second is suggested. There are two independent events: the timer expires, and a packet arrives. The processing rules for these events are: Worster, et. al. Page 71] Internet Draft General Switch Management Protocol Feb 1999 Timer Expires: Reset Timer If state = SYNSENT Send SYN If state = SYNRCVD Send SYNACK If state = ESTAB Send ACK Packet Arrives: If incoming message is an RSTACK: If (A && C && !SYNSENT) Reset the link Else Discard the message. If incoming message is a SYN, SYNACK, or ACK: Response defined by the following State Tables. If incoming message is any other GSMP message and state != ESTAB: Discard incoming message. If state = SYNSENT Send SYN (Note 1) If state = SYNRCVD Send SYNACK (Note 1) Note 1: No more than two SYN or SYNACK messages should be sent within any time period of length defined by the timer. o State synchronization across a link is considered to be achieved when the protocol reaches the ESTAB state. All GSMP messages, other than adjacency protocol messages, that are received before synchronization is achieved will be discarded. State Tables State: SYNSENT +======================================================================+ | Condition | Action | New State | +====================+=====================================+===========+ | SYNACK && C | Update Peer Verifier; Send ACK | ESTAB | +--------------------+-------------------------------------+-----------+ | SYNACK && !C | Send RSTACK | SYNSENT | +--------------------+-------------------------------------+-----------+ | SYN | Update Peer Verifier; Send SYNACK | SYNRCVD | +--------------------+-------------------------------------+-----------+ | ACK | Send RSTACK | SYNSENT | +======================================================================+ State: SYNRCVD Worster, et. al. Page 72] Internet Draft General Switch Management Protocol Feb 1999 +======================================================================+ | Condition | Action | New State | +====================+=====================================+===========+ | SYNACK && C | Update Peer Verifier; Send ACK | ESTAB | +--------------------+-------------------------------------+-----------+ | SYNACK && !C | Send RSTACK | SYNRCVD | +--------------------+-------------------------------------+-----------+ | SYN | Update Peer Verifier; Send SYNACK | SYNRCVD | +--------------------+-------------------------------------+-----------+ | ACK && B && C | Send ACK | ESTAB | +--------------------+-------------------------------------+-----------+ | ACK && !(B && C) | Send RSTACK | SYNRCVD | +======================================================================+ State: ESTAB +======================================================================+ | Condition | Action | New State | +====================+=====================================+===========+ | SYN || SYNACK | Send ACK (note 2) | ESTAB | +--------------------+-------------------------------------+-----------+ | ACK && B && C | Send ACK (note 3) | ESTAB | +--------------------+-------------------------------------+-----------+ | ACK && !(B && C) | Send RSTACK | ESTAB | +======================================================================+ Note 2: No more than two ACKs should be sent within any time period of length defined by the timer. Thus, one ACK must be sent every time the timer expires. In addition, one further ACK may be sent between timer expirations if the incoming message is a SYN or SYNACK. This additional ACK allows the adjacency protocol to reach synchronization more quickly. Note 3: No more than one ACK should be sent within any time period of length defined by the timer. 10.3 Loss of Synchronization If after synchronization is achieved, no valid GSMP messages are received in any period of time in excess of three times the value of the Timer field announced in the incoming adjacency protocol messages, loss of synchronization may be declared. The preferred procedure for a switch to use when it looses synchronization with its active controller is to attempt to establish synchronization with (one of) its backup controller(s). However, in this preferred approach, it must not reset its state until it achieves synchronization with a backup controller. This Worster, et. al. Page 73] Internet Draft General Switch Management Protocol Feb 1999 means that if, before achieving synchronization with a backup controller, it regains synchronization with its original controller, it may continue the original session (and cease attempting to establish synchronization with a backup controller). If synchronization with the original session is regained it is the responsibility of the controller to ensure consistent state between the switch and controller. While the above is the preferred procedure, it is also the case that the simplest procedure when declaring loss of synchronization with the active controller is to reset the switch state, and start searching for a controller. This simple procedure is legitimate. 11. Summary of Failure Response Codes [Editor's note: this section is currently out of whack w.r.t. the rest of the spec and will be updated in a future revision of the draft.] The following list gives a summary of the failure codes defined for failure response messages: 1: Unspecified reason not covered by other failure codes. 2: Invalid request message. 3: The specified request is not implemented on this switch. 4: Invalid Port Session Number. 5: One or more of the specified ports does not exist. 6: One or more of the specified ports is down. 7: Unused. (This failure code has been replaced by failure codes 18--21.) 8: The specified connection does not exist. 9: The specified branch does not exist. 10: A branch belonging to the specified point-to-multipoint connection is already established on the specified output port and the switch cannot support more than a single branch of any point-to-multipoint connection on the same output port. 11: The limit on the maximum number of point-to-multipoint connections that the switch can support has been reached. 12: The limit on the maximum number of branches that the specified point-to-multipoint connection can support has been reached. 13: Unable to assign the requested Label value to the requested branch on the specified point-to-multipoint connection. 14: General problem related to the manner in which point-to- multipoint is supported by the switch. Worster, et. al. Page 74] Internet Draft General Switch Management Protocol Feb 1999 15: Out of resources (e.g. memory exhausted, etc.). 16: Failure specific to the particular message type. (The meaning of this failure code depends upon the Message Type. It is defined within the description of any message that uses it.) 17: Cannot label each output branch of a point-to-multipoint tree with a different label. 18: One or more of the specified input VPIs is invalid. 19: One or more of the specified input VCIs is invalid. 20: One or more of the specified output VPIs is invalid. 21: One or more of the specified output VCIs is invalid. 22: Invalid Class of Service field in a Connection Management message. 23: Insufficient resources for QoS Profile. 24: Virtual path switching is not supported on this input port. 25: Point-to-multipoint virtual path connections are not supported on either the requested input port or the requested output port. 26: Attempt to add a virtual path connection branch to an existing virtual channel connection. 27: Attempt to add a virtual channel connection branch to an existing virtual path connection. 28: Only point-to-point bidirectional connections may be established. 29: Cannot support requested VPI range. 30: Cannot support requested VCI range on all requested VPIs. 31: The transmit cell rate of this output port cannot be changed. 32: Requested transmit cell rate out of range for this output port. 128: Weighted scheduling within this waiting room is unavailable. 129: This waiting room is unable to offer weighted sharing for a QoS class. 130: This waiting room is unable to offer weighted sharing for a connection. 131: Scheduler Identifier still in use. 132: QoS Class Identifier still in use. 133: Invalid QoS parameter. 134: Insufficient QoS resources. 135: Any point-to-multipoint connection arriving on this input port must use the same QoS parameters for all output branches. Worster, et. al. Page 75] Internet Draft General Switch Management Protocol Feb 1999 12. Summary of Message Set [Editor's note: this section is currently out of whack w.r.t. the rest of the spec and will be updated in a future revision of the draft.] The following table gives a summary of the messages defined in this version of the specification. It also indicates which messages must be supported in a minimal implementation of the protocol. Those messages marked as "Required" must be supported by the switch for an implementation to be considered to conform to this specification. (While the controller should also implement those messages marked "Required," conformance cannot be tested for the controller due to the Master-Slave nature of the protocol.) Message Name Message Type Status Connection Management Messages Add Branch VCC....................16 Required VPC....................26 Delete Tree.......................18 Delete All........................20 Delete Branches...................17 Required Move Branch VCC...................22 VPC...................27 Port Management Messages Port Management...................32 Required Label Range.......................33 State and Statistics Messages Connection Activity...............48 Port Statistics...................49 Required Connection Statistics.............50 QoS Class Statistics..............51 Report Connection State...........52 Configuration Messages Switch Configuration..............64 Required Port Configuration................65 Required All Ports Configuration...........66 Required Event Messages Worster, et. al. Page 76] Internet Draft General Switch Management Protocol Feb 1999 Port Up...........................80 Port Down.........................81 Invalid Label...................82 New Port..........................83 Dead Port.........................84 Quality of Service Messages QoS Configuration.................96 Scheduler Establishment...........97 QoS Class Establishment...........98 QoS Release.......................99 QoS Connection Management VCC....100 VPC....101 Adjacency Protocol....................10 Required 13. Security Considerations Security considrations are not addressed in the current revision of the draft. References [1] ATM Forum Traffic Management Specification 4.0, af-tm- 0056.000, April 1996. [2] "B-ISDN ATM Layer Specification," International Telecommunication Union, ITU-T Recommendation I.361, Mar. 1993. [3] "B-ISDN ATM Adaptation Layer (AAL) Specification," International Telecommunication Union, ITU-T Recommendation I.363, Mar. 1993. [4] Ipsilon IP Switch MIB, http://www.ipsilon.com/products/ips.mib. [Editor's note: this reference is obsolete. The reference must be removed if a suitable updated publication cannot be found as a replacement.] [5] Reynolds, J., and J. Postel, "Assigned Numbers," STD 2, RFC 1700, October 1994. [6] Newman, P, Edwards, W., Hinden, R., Hoffman, E. Ching Liaw, F., Lyon, T. and Minshall, G., "Ipsilon's General Worster, et. al. Page 77] Internet Draft General Switch Management Protocol Feb 1999 Switch Management Protocol Specification," Version 1.1, RFC 1987, August 1996. [7] Newman, P, Edwards, W., Hinden, R., Hoffman, E., Ching Liaw, F., Lyon, T. and Minshall, G., "Ipsilon's General Switch Management Protocol Specification," Version 2.0, RFC 2397, March 1998. Authors' Addresses Tom Worster GDC 199 W Newton St Boston MA 02116 USA 617 247 2624 tom.worster@gdc.com Worster, et. al. Page 78]