Internet Draft INTERNET DRAFT Avri Doria GSMP Working Group Nokia Informational Kenneth Sundell Nortel Networks 10 March, 2000 Requirements for adding Optical Switch Support to GSMP <draft-doria-gsmp-req-olsr-00.txt> 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. Abstract This memo provides an overview of the requirements on the GSMP protocol for support of optical switching. Doria, Sundell Expires October, 2000 [Page 1] Internet Draft Requirements for OLSR support Jan 2000 1. Overview This draft is intended to open up discussion of the required changes to GSMP for support of optical (WDM or DWDM) switching of IP packets and flows. It is uncertain at this point what the mix of implementations will be, but the possibilities include: IP based optical routers, optical label switches, wavelength routers, and optical crossconnects. There are also several different generic models that might be applied to running IP over WDM.[7] One item which seems probable, however, is that it will be advantageous to separate the control plane functions from the data plane functions in order to provide a more flexible network architecture.[4] In this draft, no position will be taken about the eventual architectural model which will be most appropriate for IP over WDM. The only assumption is that the ability to separate the control plane from the data plane is as useful in IP over WDM as it is in current MPLS technology. GSMP[3] is well suited for providing the optical switch control mechanism necessary for allowing an IP based controller to direct the activities of an optical switch. In order for GSMP to operate between IP controllers and optical switches and cross connects, support for optical labels and service and resource abstractions must be added to GSMP. 2. Connection Management Issues The current connection management commands shouldn't need to be changed to support optical switches. There will, however, need to be new label types defined. Optical labels are too long to use the GSMP short labels, and will therefore require that a new set of TLVs be created. There are two options for this that are explored below. 2.1 Single Optical Label TLV An "optical" label TLV is needed in order to encode optical labels. However a label in an MPLS enabled optical network may represent any of the following: A fiber bundle An arbitrary number of fibers in that bundle A single fiber An arbitrary number of lambdas within a fiber A single fiber Doria, Sundell Expires October , 2000 [Page 2] Internet Draft Requirements for OLSR support Jan 2000 An arbitrary number of sub-lambda channels A single sub-lambda channel One way to support these assumptions/requirements in GSMP would be to provide a single (but complicated) optical label TLV which would accommodate all the ways of expressing a label. A general format would be as follows: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |T|S|x|x| Optical Label (0x3xx) | Label Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Label Component 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ ... ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Label Component N | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Each of the label components would encode the variants of channel group types such as Fiber, Lambda, Gigabit Ethernet, SONET (with line rate specified) etc. T: Label Type Indicator T = 0: Short 28 bit Label T = 1: TLV label Both label types are discussed below in [3] (section 3.1.3.1 and 3.1.3.2). S: Stacked Label Indicator Label Stacking is discussed in [3] (section 3.1.3.3) X: Reserved Flags. These are generally used by specific messages and will be defined in those messages. Doria, Sundell Expires October , 2000 [Page 3] Internet Draft Requirements for OLSR support Jan 2000 2.2 Separate Variant Labels Or as an alternative we could use one label tlv for each variant as follows: 2.2.1 Fiber Label TLV 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |T|S|x|x| Fiber Label (0x3xx) | Label Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Fiber ID | Lambda ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ ... ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Fiber ID | Lambda ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ If the group type is fiber, the all lambda id fields should be 0x0000 or 0xffff as other have suggested. An alternative could be to use the Lambda Label TLV specified below for expressing a fiber label with the Lambda ID set as proposed above. 2.2.2 Lambda Label TLV 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |T|S|x|x| Lambda Label (0x3xx) | Label Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Fiber ID | Lambda ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ ... ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Fiber ID | Lambda ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ An optical label may be composed of fiber id's and lambdas. The Fiber ID identifies the physical fiber(s) and the Lambda ID identifies the individual Lambda(s). This label tlv could describe what lambdas to use in one or several fibers. Doria, Sundell Expires October , 2000 [Page 4] Internet Draft Requirements for OLSR support Jan 2000 2.2.3 SONET/SDH Label TLV 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |T|S|x|x|SDH/SONET Label (0x3xx)| Label Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Fiber ID | Lambda ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Channel ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The channel Id identifies the line rate that is used, e.g. OC-48, OC-192 in STM-1 channel steps (representing each bit) as proposed in [5]. 3. Port and Label Management Issues 3.1 Port Management Message No changes are currently seen as needed in the port management message. 3.2 Label Range Message An updated label range message is needed. An example of Lambda label ranges below. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |T|Q|V|M| Lambda Label (0x3xx) | Label Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Fiber ID | Minimum Lambda ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | Maximum Lambda ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remaining Lambda ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Label Range for a Specific Fiber ID (or port). There is also a need to address the support of multiplexing (e.g. no multiplexing, SONET multiplexing, Gigabit Ethernet multiplexing etc). Doria, Sundell Expires October , 2000 [Page 5] Internet Draft Requirements for OLSR support Jan 2000 The semantics of T, Q, V and M bits are GSMP specific and described in [3] (chapter 5.2). 4. Statistics messages No changes are currently proposed for the statistics messages to support optical switching. 5. Configuration Issues 5.1 Switch Configuration No changes are currently proposed for the switch configuration messages to support optical switching. 5.2 Port Configuration The port configuration message supplies the controller with the configuration information related to a single port. In order to handle the specific port types in a WDM switch, extensive additions will need to be made to this command. Port types will need to be added to support the mix of SONET signals that can operate over a single fiber. Information that may need to be conveyed includes[7]: - wavelengths available on the fiber - serial bit rate per wavelength - type of fiber 5.3 Service Configuration While new capability sets will need to be added to support quality parameters in optical switches, no changes are foreseen to the service configuration message as its role to carry the service information as defined in the applicable service model. The changes related to the service model will be discussed in section 6. 6. Service Model issues While one assumption of using optical media is that bandwidth is plentiful, it should be expected that traffic engineering will be necessary in any case[4]. GSMP provides the means for each Doria, Sundell Expires October , 2000 [Page 6] Internet Draft Requirements for OLSR support Jan 2000 connection, or in this each light trail, to be created with specific quality attributes. Certainly re-timing and re-shaping will need to be controlled. Currently, the default set of service models in GSMP are all based on the services models defined elsewhere, e.g. the intserv model, the diffserv model, ATM QoS models and the Frame relay forum QoS models. A determination needs to be made of the applicable quality models for optical channel trails. These models must then be mapped to the GSMP capability set mechanism. 7. Encapsulation issues The working group needs to decide whether a new encapsulation is required. In other words, will all optical switches used in either the MPLS over Optics and the IP over optics applications require that IP be implemented on the control channel connecting the GSMP controller and Optical switch (the GSMP target). If a raw wavelength control connection is to be allowed, a new encapsulation will need to be added to the encapsulation document.[2] The authors of this draft recommend that IP be required on the control channel. 8. MIB issues If a new encapsulation is defined, then the encapsulation group will need to be updated. No other changes should be required. 9. Security Considerations The security of GSMP's TCP/IP control channel has been addressed in [2]. Any potential remaining security considerations are not addressed in the current revision of this draft. References [1] Sjostrand, H., "Definitions of Managed Objects for the General Switch Management Protocol (GSMP)," Internet-Draft draft-ietf-gsmp-mib-00 (work in progress), September 1999. [2] T. Worster, "GSMP Packet Encapsulations for ATM, Ethernet and TCP," Internet-Draft draft-ietf-gsmp-encaps-00 (work in progress), Jan 2000. Doria, Sundell Expires October , 2000 [Page 7] Internet Draft Requirements for OLSR support Jan 2000 [3] Doria, A, Sundell, K, Hellstrand, F, Worster, T, "General Switch Management Protocol V3," Internet Draft draft-ietf- gsmp-04.txt (work in progress), March 2000 [4] Awduche, D, Rekhter, Y, et. al., "Multi-Protocol Lambda Switching: Combining MPLS Traffic Engineering Control with Optical Crossconnects," draft-awduche-mpls-te-optical- 01.txt (work in progress), November, 1999 [5] Fan, Y, Ashwood-Smith, P, et. al. "Extensions to CR-LDP and RSVP-TE for Optical Path Set-up," draft-fan-mpls- lambda-signaling-00.txt" (work in progress), March 2000 [6] Wang, G, Fedyk, D, et al, " Extensions to OSPF/IS-IS for Optical Routing," draft-wang-isis-lambda-te-routing-00.txt (work in progress), March 2000 [7] Luciani, J, Awduche, D, "IP over WDM: A framework,", draft-lucinai-ip-over-wdm-00.txt (work in progress), March 2000 [8] Kurki, J, Kilkki, K, Doria, A, "Wavelength Router As a Transport Platform for IP", Paper to be presented in European Conference on Networks and Optical Communications, NOC 2000, June 6-9, 2000, Stuttgart, Germany Authors' Addresses Avri Doria Nokia Internet Communications 5 Wayside Road Burlington MA 01803 Phone: +1 781 993 4656 avri.doria@nokia.com Kenneth Sundell Nortel Networks AB S:t Eriksgatan 115 A P.O. Box 6701 SE-113 85 Stockholm Sweden ksundell@nortelnetworks.com Doria, Sundell Expires October , 2000 [Page 8]