Internet Draft
MPLS Working Group                       Ken-ichi Nagami (Toshiba Corp.)
INTERNET DRAFT                          Noritoshi Demizu (NAIST)
                                           Hiroshi Esaki (Toshiba Corp.)
                                         Paul Doolan (Ennovate Networks)
                                                             August 1998
                                                   Expires February 1999


                    VCID Notification over ATM link
                   <draft-ietf-mpls-vcid-atm-01.txt>

Status of this memo

   This document is an Internet-Draft.  Internet-Drafts are working
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Abstract

   The ATM Label Switching Router (ATM-LSR) is one of the major
   applications of label switching. Because the ATM layer labels (VPI
   and VCI) associated with a VC may change on each VC of that VC, it is
   not possible to use them to identify a VC in label binding
   messages. The concept of Virtual Connection Identifier (VCID) is
   introduced to solve this problem.  VCID has the same value at both
   ends of a VC.  This document specifies the procedures for the
   communication of VCID values between neighboring ATM-LSRs that must
   occur in order to ensure this property.


1. Introduction

   Several label switching schemes have been proposed to integrate Layer
   2 and Layer 3.  The ATM Label Switching Router (ATM-LSR) is one of the
   major applications of label switching.

   In the case of ATM VCs, the VPI and VCI labels are, in the general
   case, rewritten with new values at every switch node through which
   the VC passes and cannot be used to provide end to end
   identification of a VC.

   In the context of MPLS 'stream', which are classes of packets that
   have some common charachteristic that may be deduced by examination
   of the layer 3 header in the packets, are bound to layer 2 'labels'. 
   We speak of stream being 'bound' to labels.  These bindings are
   conveyed between peer LSRs by means of a Label Distribution Protocol
   [LDP].

   In order to apply MPLS to ATM links, we need some way to identify ATM
   VCs in LDP binding messages. In [VCID], an identifier called a
   Virtual Connection ID (VCID) is introduced. VCID has the same value
   at both ends of a VC.  This document specifies the procedures for
   the communication of VCID values between neighboring ATM-LSRs that
   must occur in order to ensure this property.


2. Overview of VCID Notification Procedures

2.1 VCID Notification procedures

   The ATM has several types of VCs (transparent point-to-point
   link/VP/PVC/SVC). A transparent point-to-point link is defined as one
   that has the same VPI/VCI label at both ends of a VC.  For example,
   two nodes are directly connected (i.e., without intervening ATM
   switches) or are connected through a VP with the same VPI value at
   both ends of the VP.

   There are two broad categories of VCID notification procedures;
   inband and out of band. The categorisation refers to the connection
   over which the messages of the VCID notification procedure are
   forwarded. In the case of the inband procedures, those messages are
   forwarded over the VC to which they refer. In contrast the out of
   band procedures transmit the messages over some other connection
   (than the VC to which they refer).

   We list below the various types of link and briefly mention the VCID
   notification procedures employed and the rational for that
   choice. The procedures themselves are discussed in detail in later
   sections.


   Transparent point-to-point link : no VCID notification
      VCID notification procedure is not necessary because the label
      (i.e., VPI/VCI) is the same at each end of the VC.

   VP : inband notification (as a default mechanism)
    - Inband notification
      VCID notification is needed because the VPI at each end of the VC
      may not be the same. Inband VCID notification [VCID] is used in
      this case.

    - No notification
      If a node has only one VP to a neighboring node, VCID notification
      procedure is not mandatory. The VCI can be used as the VCID. This
      is because the VCI value is the same at each end of the VP.

   PVC : inband notification
      Inband VCID notification [VCID] is used in this case because the
      labels at each end of the VC may not be the same.

   SVC : there are three possibilities
    - Out of band notification
      If a signaling message has a field which is large enough to carry
      a VCID value (e.g., GIT [GIT]), then the VCID is carried directly
      in it.

    - Outband notification using a small-sized field
      If a signaling message has a field which is not large enough to
      carry a VCID value, this procedure is used.

    - Inband notification
      If a signaling message can not carry user information, this
      procedure is used.

      When an LSP is a point-to-multipoint VC and an ATM switch in an
      LSR is not capable of VC merge, it may cause problems in
      performance and quality of service.  When the LSR wants to add a
      new leaf to the LSP, it needs to split the active LSP temporarily
      to send an inband notification message.


2.2 VCID Assignment

   A VCID value is assigned by either an upstream node or a downstream
   node depending on the type of VC.  For a point-to-point VC, either
   the upstream node or the downstream node could assign a VCID
   value. For a point-to-multipoint VC, only an upstream (root) node can
   assign a VCID value.


3. VCID Notification Procedures

3.1 Inband Notification Procedures

3.1.1 Inband Notification for Point-to-point VC

   VCID notification is performed by transmitting a control message
   through the VC newly established (by signalling or management) for
   use as an label switched path (LSP) [FRAME], The procedure for VCID
   notification between two nodes A and B is detailed below.

   0. Node A establishes a VC to the destination LSR B. (by signalling
      or management)

   1. Node A selects a VCID value.

   2. Node A sends a message which contains the VCID value through the
      newly established VC to Node B.

   3. Node A establishes an association between the outgoing label
      (VPI/VCI) for the VC and the VCID value.

   4. Node B receives the message from the VC and establishes an
      association between the VCID in the message and the incomming
      label(VPI/VCI) for the VC.

   5. Node B sends an ACK message to node A.

   6. After Node A receives the ACK message, node A and node B both
      associate the VCID with the same VC.

       Node A           Node B
         |                |
         |--------------->|
         |     VCID       |
         |                |
         |<---------------|
         |      ACK       |


3.1.2 Inband notification for point-to-multipoint VC

   VCID notification is performed by sending a control message through
   the VC to be used as an LSP. The upstream node must assign the VCID
   value. The procedure by which it notifies the downstream node of that
   value is given below. The procedure is used when a new VC is created
   or a new leaf is added to the VC.

   First, the procedure for establishing the first VC is described.

   1. The upstream node assigns a VCID value for the VC.  When the VCID
      value is already assigned to a VC, it is used for VCID.

   2. The upstream node sends a message which contains the VCID value
      and the address of the upstream node through the VC used for a
      label switched path. This message is transferred to all leaf
      nodes.

   3. The upstream node establishes an association between the outgoing
      label for the VC and the VCID value.

   4. The downstream nodes receiving the message check the address of
      the upstream node. If the address is not the same network prefix
      as its address, the message is discarded. Otherwise, the
      downstream nodes establish an association between the VCID in the
      message and the VC from which the message is received.

   5. The downstream nodes send an ACK message to the upstream node.

   6. After the upstream node receives the ACK messages, the upstream
      node and the downstream nodes share the VCID.

       Upstream        Downstream 1   Downstream 2
         |                |               |
         |-----------+--->|               | 
         |     VCID  +------------------->|
         |                |               |
         |<---------------|               |
         |      ACK       |               |
         |<-------------------------------|
         |              ACK               |


   Second, the procedure for adding a leaf to the existing
   point-to-multipoint VC is described.

   0. The upstream node adds the downstream node, using the ATM
      signaling.

   1. The VCID value which already assigned to the VC is used.

   2. The upstream node sends a message which contains the VCID value
      and the address of the upstream node through the VC used for a
      label switched path. This message is transferred to all leaf
      nodes.

   3. The downstream nodes receiving the message check the address of
      the upstream node. If the address is not the same network prefix
      as its address, the message is discarded. Otherwise, the
      downstream nodes establish an association between the VCID in the
      message and the VC from which the message is received.

   4. After the upstream node receives the ACK messages, the upstream
      node and the downstream nodes share the VCID.



3.2 Outband Notification using a small-sized field

   This method can be applied when a VC is established using an ATM
   signaling message and the message has a field which is not large
   enough to carry a VCID value.

   SETUP message of the ATM Forum UNI 3.1/4.0 has a 7-bit mandatory
   field for the user. This is a user specific field in the Layer 3
   protocol field in the BLLI IE (Broadband Low Layer Information
   Information Element).

   The BLLI value is used as a temporary identifier for a VC during a
   VCID notification procedure.  This mechanism is defined as "Outband
   Notification using a small-sized field" described in [VCID]. The BLLI
   value of a new VC must not be assigned to other VCs during the
   procedure to avoid identifier conflict.  When the association among
   the BLLI value, a VCID value, and the corresponding VC is
   established, the BLLI value can be reused for a new VC. VCID values
   can be assigned independently from BLLI values.

       Node A           Node B
         |                |
         |<-------------->|
         | ATM Signaling  |
         | with BLLI      |
         |                |
         |--------------->|
         |  BLLI & VCID   |
         |                |
         |<---------------|
         |      ACK       |

   A point-to-multipoint VC can also be established using ADD_PARTY of
   the ATM Forum Signaling.  ADD_PARTY adds a new VC leaf to an existing VC
   or an existing VC tree.  In this procedure, the BLLI value of
   ADD_PARTY has to be the same value as that used to establish the
   first point-to-point VC of the tree.  The same BLLI value can be used
   in different VC trees only when these VC trees can not add a leaf at
   the same time. As a result, the BLLI value used in the signaling must
   be determined by the root node of the multicast tree.

   [note]
      BLLI value is unique at the sender node.  But BLLI value is not
      unique at the reciever node because multiple sender nodes may
      allocate the same BLLI value.  So, the receiver node must
      recognize BLLI value and the sender address.  ATM Signaling
      messages(SETUP and ADD_PARTY) carry both the BLLI and the sender
      ATM address.  The receiver node can realize which node sends the
      BLLI message.


3.2.1 Outband notification using a small-sized field for point-to-point VC

   This subsection describes procedures for establishing a VC and for
   notification of its VCID between neighboring LSRs for unicast
   traffic.  VC pool [VCPOOL] can be applied.

   For point-to-point VC, either an upstream LSR or a downstream LSR can
   allocate a VCID for a new VC.

   The procedure employed when the upstream LSR assigns a VCID is as
   follows.

   1. An upstream LSR establishes a VC to the downstream LSR using ATM
      signaling and supplies a value in the BLLI field that it is not
      currently using for any other (incomplete) VCID notification
      transaction with this peer.

   2. The upstream LSR notifies the downstream LSR of the association
      between the BLLI and VCID values.

   3. The downstream LSR establishes the association between the VC
      with the BLLI value and the VCID and sends an ACK message to the
      upstream LSR.  If the VCID is associated with some other VC
      between the upstream and downstream LSRs, that old VC is removed
      from service.

   4. After the upstream LSR receives the ACK message, it establishes
      the association between the VC and the VCID. The VC is ready to
      be used. At this time the BLLI value employed in this transaction
      is free for reuse.

   The procedure employed when a downstream LSR assigns a VCID is
   as follows:

   1. An upstream LSR establishes a VC by ATM signaling between the
      downstream LSR with a unique BLLI value at this time.

   2. The downstream LSR notifies the upstream LSR of a paired BLLI
      value and VCID using a message dedicated for this purpose.

   3. The upstream LSR establishes the association between the VC with
      the BLLI value and the VCID and sends an ACK message to the
      downstream LSR. If the VCID is associated with some other VC
      between the upstream and downstream LSRs, that old VC is removed
      from service.

   4. After the downstream LSR receives the ACK message, it establishes
      the association between the VC and the VCID.  The VC is ready to
      be used.At this time the BLLI value employed in this transaction
      is free for reuse.


3.2.2 Outband notification using a small-sized field
      for point-to-multipoint VC

   This subsection describes procedures for establishing the first VC
   for a multicast tree and for adding a new VC leaf to an existing VC
   tree including the notification of its VCID for a multicast stream
   using point-to-multipoint VCs.

   In this procedure, an upstream LSR determines both the VCID and BLLI
   value in the multicast case.  The reason that the BLLI value is
   determined by an upstream LSR is described above.

   First, the procedure for establishing the first VC is described.

   1. An upstream LSR establishes a VC by the ATM Forum Signaling between
      the downstream LSR with a unique BLLI value at this time.

   2. The upstream LSR notifies the downstream LSR of a paired BLLI
      value and VCID using a message dedicated for this purpose.

   3. The downstream LSR establishes the association between the VC with
      the BLLI value and the VCID and sends an ACK message to the
      upstream LSR.  If the VCID is used by some other VC between the
      upstream and downstream LSRs, the old VC is discarded.

   4. After the upstream LSR receives the ACK message, the VC is ready
      to be used and the BLLI value can be used for another VC.

   Second, the procedure for adding a leaf to the existing
   point-to-multipoint VC is described.

   1. The upstream LSR establishes a VC by the ATM Forum Signaling between
      its downstream LSR with the BLLI value that was used during the
      first signaling procedure.  If another VC is using the BLLI value
      at the same time, the upstream waits for the completion of the
      signaling procedure that is using this BLLI value.

   2. Go to step 2 of the procedure for the first VC.


3.3 Outband notification

   This method can be applied when a VC is established using a ATM
   signaling message and the message has a field (e.g., GIT [GIT]) which
   is large enough to carry a VCID value. Message format is described in
   [GIT].

       Node A           Node B
         |                |
         |<-------------->|
         | ATM Signaling  |
         | with VCID      |


4 VCID Message Format
4.1 VCID Class Messages

   VCID class messages are added to the LDP specification [LDP].  An LDP
   VCID PDU consists of an LDP common header followed by one or more
   objects.  VCID PROPOSE inband message is sent as a null encapsulation
   packet through a VC to be used as an LSP.  A label value in the label
   stack entry for VCID PROPOSE inband message is 4, that should be
   added as a reserved label value to the section 2.1 of [ENCAPS].
   Other messages are sent as TCP packets.

   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      |   Msg Class   |       PDU Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        LDP Identifier                         |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |       Reserved                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Msg Type   |    Reserved   |         Msg Length            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        Mandatory Objects                      |
   |                       (Variable  Length)                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        Optional Objects                       |
   |                       (Variable  Length)                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Version
        One octet unsigned integer containing the version number of the
        protocol.  This version of the specification specifies protocol
        Version = 0x01.

   Msg Class
        One octet integer defining the class of the LDP message.
        VCID Class            = 0x04

   PDU Length
        Two octet integer specifying the total length of this PDU in
        bytes, excluding the common header.

   LDP Identifier
        Six octet field that uniquely identifiers the label space for
        which this PDU applies.  The first four octets encode an IP
        address assigned to the LSR.  This address should be the router-
        id, also used in LSR-path-vector loop detection/prevention
        objects.  The last two octets identify a label space within the
        LSR.  For a platform-wide label space, these should both be
        zero.

   Reserved
        This field is reserved. It must be set to zero on transmission
        and must be ignored on receipt.

   Msg Type
        The MsgType field identifies the type of message.  The following
        discovery messages are supported:
        VCID Propose inband Message  = 0x01
	VCID Propose Message         = 0x02
	VCID ACK Message             = 0x02
	VCID NACK Message            = 0x03

   Msg Length
        Two octet integer specifying the total length of all objects
        associated with the message type.

4.1.1 VCID Propose inband Message

   This message is sent as a null encapsulation packet with a label
   value 4 through a VC to be used as an LSP.

   Mandatory Objects
   At least one of each mandatory object with associated object headers.

   +-----------------------+----------+
   | MANDATORY OBJECT      | Type     |
   +-----------------------+----------+
   | VCID                  | 0x01     |
   +-----------------------+----------+
   | Address               | 0x03     |
   +-----------------------+----------+

4.1.2 VCID Propose Message

   Mandatory Objects
   At least one of each mandatory object with associated object headers.

   +-----------------------+----------+
   | MANDATORY OBJECT      | Type     |
   +-----------------------+----------+
   | VCID                  | 0x01     |
   +-----------------------+----------+
   | Temporary ID          | 0x02     |
   +-----------------------+----------+


4.1.3 VCID ACK Message

   Mandatory Objects
   At least one of each mandatory object with associated object headers.

   +-----------------------+----------+
   | MANDATORY OBJECT      | Type     |
   +-----------------------+----------+
   | VCID                  | 0x01     |
   +-----------------------+----------+

4.1.4 VCID NACK Message

   Mandatory Objects
   At least one of each mandatory object with associated object headers.

   +-----------------------+----------+
   | MANDATORY OBJECT      | Type     |
   +-----------------------+----------+
   | VCID                  | 0x01     |
   +-----------------------+----------+


4.2 VCID Class Objects
4.2.1 Object Header

   All objects in a VCID message must begin with the following object
   header.  This header is the same as LDP specification.

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Obj Type   |   Sub Type    |         Length                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Object Type
          VCID_OBJECT         = 0x01
          TEMPORARY_ID_OBJECT = 0x02
          ADDRESS_OBJECT      = 0x03

4.2.2 VCID Object

   +-----------------------+-------+--------------------------+----------+
   | OBJECT                | Type  |  Subtype(s)              | Length   |
   +-----------------------+-------+--------------------------+----------+
   | VCID                  | 0x01  |  0x01  Default           |    4     |
   +-------------------------------+--------------------------+----------+

   Subtype = 0x01 Default

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            VCID                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


4.2.3 Temporary ID Object

   +-----------------------+-------+--------------------------+----------+
   | OBJECT                | Type  |  Subtype(s)              | Length   |
   +-----------------------+-------+--------------------------+----------+
   | Temporary ID          | 0x02  |  0x01  BLLI              |    1     |
   +-------------------------------+--------------------------+----------+

   Subtype = 0x01  Default

    0                 
    0 1 2 3 4 5 6 7 8 
   +-+-+-+-+-+-+-+-+-+
   |      BLLI       |
   +-+-+-+-+-+-+-+-+-+


4.2.4 Address Object

   +-----------------------+-------+--------------------------+----------+
   | OBJECT                | Type  |  Subtype(s)              | Length   |
   +-----------------------+-------+--------------------------+----------+
   | Address               | 0x02  |  0x01  Default           | variable |
   +-------------------------------+--------------------------+----------+

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |      Address List Family      |Source Address (variable length)
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          . . . .                                                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Destination Address (variable length)                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Address Family
      This 16 bit quantity contains a value from ADDRESS FAMILY NUM-
      BERS in Assigned Numbers [RFC1700] that encodes the address family
      that the network layer addresses in the Addresses field are from.

   Addresses
      Two addresses encoded according to the Address Family Field,
      padded to a 16-bit boundary. First address is a source address of
      this object. Second address is a destination address of this
      object.


4.3 Mapping messages
4.3.1 Label Object

   An VCID subtype is added to label object of an advertisment class
   message in the LDP specification.  This object is used for a label
   mapping between SMD and VCID.

   +-----------------------+-------+--------------------------+----------+
   | OBJECT                | Type  |  Subtype(s)              | Length   |
   +-----------------------+-------+--------------------------+----------+
   | Label                 | 0x03  |  0x03  VCID              |    4     |
   +-------------------------------+--------------------------+----------+

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            VCID                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


Security Considerations

   Security issues are not discussed in this document.


Intellectual Property Considerations

   Toshiba Corporation and Ennovate Networks may seek patent or other
   intellectual property protection for some of the aspects of the
   technology discussed in this document.  If any standards arising from
   this document are or become protected by one or more patents assigned
   to Toshiba Corporation, Toshiba intends to license them on reasonable
   and non- discriminatory terms.


Acknowledgments

   The authors would like to acknowledge the valuable technical comments
   of Shigeo Matsuzawa, Akiyoshi Mogi, Yasuhiro Katsube, Muneyoshi
   Suzuki, George Swallow and members of the LAST-WG of the WIDE Project.


References

   [VCID] N. Demizu, et al., "VCID: Virtual Connection Identifier",
      draft-demizu-mpls-vcid-01.txt, Oct. 1997

   [VCPOOL] N. Demizu, et al., "VC pool",
      draft-demizu-mpls-vcpool-00.txt, Oct. 1997

   [FRAME] R. Callon, et al., "A Framework for Multiprotocol Label
      Switching", draft-ietf-mpls-framework-02.txt, Nov. 1997

   [GIT] M. Suzuki, "The Assignment of the Information Field and
      Protocol Identifier in the Q.2941 Generic Identifier and Q.2957
      User-to-user Signaling for the Internet Protocol",
      draft-ietf-mpls-git-uus-assignment-00.txt, June 1998

   [ENCAPS] E. Rossen, et al., "MPLS Label Stack Encoding",
      draft-ietf-mpls-label-encaps-02.txt, July 1998

   [rfc1700] J. Reynolds, J. Postel, "Assigned Numbers", RFC 1700, ISI,
      October 1994


Authors Information

   Ken-ichi Nagami
   R&D Center, Toshiba Corporation,
   1 Komukai-Toshiba-cho, Saiwai-ku,
   Kawasaki, 210, Japan
   Phone: +81-44-549-2231
   Email: nagami@isl.rdc.toshiba.co.jp

   Noritoshi Demizu
   Graduate School of Information Science,
   Nara Institute of Science and Technology
   8916-5 Takayama, Ikoma, Nara 630-0101, Japan
   Phone: +81-743-72-5348
   E-mail: nori-d@is.aist-nara.ac.jp

   Hiroshi Esaki
   Computer and Network Division,
   Toshiba Corporation,
   1-1-1 Shibaura,
   Minato-ku, 105-01, Japan
   Email: hiroshi@isl.rdc.toshiba.co.jp

   Paul Doolan
   Ennovate Networks
   330 Codman Hill Road
   Boxborough, MA
   Phone: 978-263-2002 x103
   Email: pdoolan@ennovatenetworks.com