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Versions: 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 RFC 4906

Network Working Group                                       Luca Martini
Internet Draft                                           Nasser El-Aawar
Expiration Date: August 2001                                 Giles Heron
                                            Level 3 Communications, LLC.

                                                           Daniel Tappan
                                                           Eric C. Rosen
                                                           Alex Hamilton
                                                     Jayakumar Jayakumar
                                                     Cisco Systems, Inc.

                                                         Steve Vogelsang
                                                            John Shirron
                                                              Toby Smith
                                                   Laurel Networks, Inc.

                                                         Andrew G. Malis
                                                            Vinai Sirkay
                                                   Vivace Networks, Inc.

                                                Dimitri Stratton Vlachos
                                                     Mazu Networks, Inc.

                                                           February 2001


                 Transport of Layer 2 Frames Over MPLS


               draft-martini-l2circuit-trans-mpls-05.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.




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   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

Abstract

   This document describes methods for transporting the Protocol Data
   Units (PDUs) of layer 2 protocols such as Frame Relay, ATM AAL5,
   Ethernet, and providing a SONET circuit emulation service across an
   MPLS network.


Table of Contents

    1      Specification of Requirements  ..........................   2
    2      Introduction  ...........................................   3
    3      Tunnel Labels and VC Labels  ............................   3
    4      Protocol-Specific Details  ..............................   4
    4.1    Frame Relay  ............................................   5
    4.2    ATM  ....................................................   5
    4.2.1  ATM AAL5 VCC Transport  .................................   5
    4.2.2  ATM Transparent Cell Transport  .........................   5
    4.2.3  ATM VCC and VPC Cell Transport  .........................   5
    4.2.4  OAM Cell Support  .......................................   6
    4.2.5  ILMI Support  ...........................................   6
    4.3    Ethernet VLAN  ..........................................   7
    4.4    Ethernet  ...............................................   7
    4.5    HDLC ( Cisco )  .........................................   7
    4.6    PPP  ....................................................   7
    4.7    Static MPLS  ............................................   7
    5      LDP  ....................................................   8
    5.1    Interface Parameters Field  .............................   9
    6      IANA Considerations  ....................................  11
    7      Security Considerations  ................................  11
    8      References  .............................................  11
    9      Author Information  .....................................  12




1. Specification of Requirements

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119.







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2. Introduction

   In an MPLS network, it is possible to carry the Protocol Data Units
   (PDUs) of layer 2 protocols by prepending an MPLS label stack to
   these PDUs. This document specifies the necessary label distribution
   procedures for accomplishing this using the encapsulation methods in
   [7]. We restrict discussion to the case of point-to-point transport.
   QoS related issues are not discussed in this draft.

   An accompanying document [8] also describes a method for transporting
   time division multiplexed (TDM) digital signals (TDM circuit
   emulation) over a packet-oriented MPLS network. The transmission
   system for circuit-oriented TDM signals is the Synchronous Optical
   Network (SONET)[5]/Synchronous Digital Hierarchy (SDH) [6]. To
   support TDM traffic, which includes voice, data, and private leased
   line service, the MPLS network must emulate the circuit
   characteristics of SONET/SDH payloads. MPLS labels and a new circuit
   emulation header are used to encapsulate TDM signals and provide the
   Circuit Emulation Service over MPLS (CEM). This encapsulation method
   is described in [8].

3. Tunnel Labels and VC Labels

   Suppose it is desired to transport layer 2 PDUs from ingress LSR R1
   to egress LSR R2, across an intervening MPLS network. We assume that
   there is an LSP from R1 to R2. That is, we assume that R1 can cause a
   packet to be delivered to R2 by pushing some label onto the packet
   and sending the result to one of its adjacencies. Call this label the
   "tunnel label", and the corresponding LSP the "tunnel LSP".

   The tunnel LSP merely gets packets from R1 to R2, the corresponding
   label doesn't tell R2 what to do with the payload, and in fact if
   penultimate hop popping is used, R2 may never even see the
   corresponding label.  (If R1 itself is the penultimate hop, a tunnel
   label may not even get pushed on.)  Thus if the payload is not an IP
   packet, there must be a label, which becomes visible to R2, that
   tells R2 how to treat the received packet.  Call this label the "VC
   label".

   So when R1 sends a layer 2 PDU to R2, it first pushes a VC label on
   its label stack, and then (if R1 is not adjacent to R2) pushes on a
   tunnel label.  The tunnel label gets the MPLS packet from R1 to R2;
   the VC label is not visible until the MPLS packet reaches R2.  R2's
   disposition of the packet is based on the VC label.

   Note that the tunnel could be a GRE encapsulated MPLS tunnel between
   R1 and R2. In this case R1 would be adjacent to R2 , and only the VC
   label would be used, and the intervening network need only carry IP



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   packets.

   If the payload of the MPLS packet is, for example, an ATM AAL5 PDU,
   the VC label will generally correspond to a particular ATM VC at R2.
   That is, R2 needs to be able to infer from the VC label the outgoing
   interface and the VPI/VCI value for the AAL5 PDU. If the payload is a
   Frame Relay PDU, then R2 needs to be able to infer from the VC label
   the outgoing interface and the DLCI value. If the payload is an
   Ethernet frame, then R2 needs to be able to infer from the VC label
   the outgoing interface, and perhaps the VLAN identifier. This process
   is unidirectional, and will be repeated independently for
   bidirectional operation. It is REQUIRED to assign the same VC ID for
   a given circuit in both directions. The transported frame MAY be
   modified when it reaches the egress router. If the header of the
   transported layer 2 frame is modified, this MUST be done at the
   egress LSR only.  Note that the VC label must always be at the bottom
   of the label stack, and the tunnel label, if present, must be
   immediately above the VC label. Of course, as the packet is
   transported across the MPLS network, additional labels may be pushed
   on (and then popped off) as needed. Even R1 itself may push on
   additional labels above the tunnel label. If R1 and R2 are directly
   adjacent LSRs, then it may not be necessary to use a tunnel label at
   all.

   This document does not specify a method for distributing the tunnel
   label or any other labels that may appear above the VC label on the
   stack. Any acceptable method of MPLS label distribution will do.

   This document does specify a method for assigning and distributing
   the VC label. Static label assignment MAY be used, and
   implementations SHOULD provide support for this.  If signaling is
   used, the VC label MUST be distributed from R2 to R1 using LDP in the
   downstream unsolicited mode; this requires that an LDP connection be
   created between R1 and R2. [1]

   Note that this technique allows an unbounded number of layer 2 "VCs"
   to be carried together in a single "tunnel".  Thus it scales quite
   well in the network backbone.

4. Protocol-Specific Details











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4.1. Frame Relay

   The Frame Relay PDUs are encapsulated according to the procedures
   defined in [7]. The MPLS edge LSR MUST provide Frame Relay PVC status
   signaling to the Frame Relay network. If the MPLS edge LSR detects a
   service affecting condition as defined in [2] Q.933 Annex A.5 sited
   in IA FRF1.1, it MUST withdraw the label that corresponds to the
   frame relay DLCI. The Egress LSR SHOULD generate the corresponding
   errors and alarms as defined in [2] on the Frame relay VC.

4.2. ATM

4.2.1. ATM AAL5 VCC Transport

   ATM AAL5 CSPS-PDUs are encapsulated according to [7] ATM AAL5 CPCS-
   PDU mode.  At the edge LSRs, R1 and R2, if ATM ILMI signaling is
   supported it SHOULD be connected to VC signaling. This mode allows
   the transport of ATM AAL5 CSPS-PDUs traveling on a particular ATM PVC
   across the mpls network to another ATM PVC.


4.2.2. ATM Transparent Cell Transport

   This mode is similar to the Ethernet port mode. Every cell that is
   received at the ingress ATM port on the ingress LSR, R1, is
   encapsulated according to [7], ATM cell mode, and sent across the LSP
   to the egress LSR, R2. This mode allows an ATM port to be connected
   to only one other ATM port. [7] allows for grouping of multiple cells
   into a single MPLS frame. Grouping of ATM cells is OPTIONAL for
   transmission at the ingress LSR, R1. If the Egress LSR R2 supports
   cell concatenation the ingress LSR, R1, should only concatenate cells
   up to the "Maximum Number of concatenated ATM cells" parameter
   received as part of the FEC element.


4.2.3. ATM VCC and VPC Cell Transport

   This mode is similar to the ATM AAL5 VCC transport except that only
   cells are transported. Every cell that is received on a pre-defined
   ATM PVC, or ATM PVP, at the ingress ATM port on the ingress LSR, R1,
   is encapsulated according to [7], ATM cell mode, and sent across the
   LSP to the egress LSR R2. Grouping of ATM cells is OPTIONAL for
   transmission at the ingress LSR, R1. If the Egress LSR R2 supports
   cell concatenation the ingress LSR, R1, MUST only concatenate cells
   up to the "Maximum Number of concatenated ATM cells in a frame"
   parameter received as part of the FEC element.





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4.2.4. OAM Cell Support

   OAM cells MAY be transported on the VC LSP. When the LSR is operating
   in AAL5 PDU transport mode if it does not support transport of ATM
   cells, the LSR MUST discard incoming MPLS frames on an ATM VC LSP
   that contain a VC label with the T bit set [7]. When operating in
   AAL5 PDU transport mode an LSR that supports transport of OAM cells
   using the T bit defined in [7], or an LSR operating in any of the
   three cell transport modes MUST follow the procedures outlined in [9]
   section 8 for mode 0 only, in addition to the applicable procedures
   specified in [6].

4.2.4.1. OAM Cell Emulation Mode

   AN LSR that does not support transport of OAM cells across an LSP MAY
   provide OAM support on ATM PVCs using the following procedures:

   If an F5 end-to-end OAM cell is received from a ATM VC by an ingress
   LSR or egress LSR, with a loopback indication value of 1 and the LSR
   has a label mapping for the ATM VC, the LSR MUST decrement the
   loopback indication value and loop back the cell on the ATM VC.
   Otherwise the loopback cell MUST be discarded by the LSR.

   The ingress LSR, R1, may also optionally be configured to
   periodically generate F5 end-to-end loopback OAM cells on a VC. If
   the LSR fails to receive a response to an F5 end-to-end loopback OAM
   cell for a pre-defined period of time it MUST withdraw the label
   mapping for the VC.

   If an ingress LSR, R1, receives an AIS F5 OAM cell, fails to receive
   a pre-defined number of the End-to-End loop OAM cells, or a physical
   interface goes down, it MUST withdraw the label mappings for all VCs
   associated with the failure. When a VC label mapping is withdrawn,
   the egress LSR, R2, MUST generate AIS F5 OAM cells on the VC
   associated with the withdrawn label mapping. In this mode it is very
   useful to apply a unique group ID to each interface. In the case
   where a physical interface goes down, a wild card label withdraw can
   be sent to all LDP neighbors, greatly reducing the signaling response
   time.


4.2.5. ILMI Support

   An MPLS edge LSR MAY provide an ATM ILMI to the ATM edge switch. If
   an ingress LSR receives an ILMI message indicating that the ATM edge
   switch has deleted a VC, or if the physical interface goes down, it
   MUST withdraw the label mappings for all VCs associated with the
   failure. When a VC label mapping is withdrawn, the egress LSR SHOULD



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   notify its client of this failure by deleting the VC using ILMI.

4.3. Ethernet VLAN

   The Ethernet frame will be encapsulated according to the procedures
   in [7].  It should be noted that if the VLAN identifier is modified
   by the egress LSR, according to the procedures outlined above, the
   Ethernet spanning tree protocol might fail to work properly.

4.4. Ethernet

   The Ethernet frame will be encapsulated according to the procedures
   in [7].  If the LSR detects a failure on the Ethernet physical port,
   or the port is administratively disabled, the corresponding VC label
   mapping MAY be withdrawn. If the egress LSR, R2, does not have a VC
   label mapping for the corresponding Ethernet port, the Ethernet port
   physical layer MAY be disabled.

4.5. HDLC ( Cisco )

   If the MPLS edge LSR detects that the physical link has failed it
   MUST withdraw the label that corresponds to the HDLC link. The Egress
   LSR SHOULD notify the CE device of this failure by using a physical
   layer mechanism to take the link out of service.

4.6. PPP

   If the MPLS edge LSR detects that the physical link has failed it
   MUST withdraw the label that corresponds to the PPP link. The Egress
   LSR SHOULD notify the CE device of this failure by using a physical
   layer mechanism to take the link out of service.

4.7. Static MPLS

   The MPLS frames encapsulated according to [3] using any layer 2
   technology that is commonly used to transport MPLS can be transported
   across the service provider MPLS network using the methods described
   in this document.  The VC label in this case is the statically
   configured label that is accepted at the ingress LSR R1, and
   advertised with an associated VC ID in LDP. The VC ID has to match in
   both directions on a particular VC. At the egress LSR, R2 a common
   MPLS label swap operation will swap the VC label with the label that
   is statically configured for this particular VC. This transport mode
   can be used to offer packet transport using different kinds of layer
   2 access infrastructures.






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5. LDP

   The VC label bindings are distributed using the LDP downstream
   unsolicited mode described in [1]. The LSRs will establish an LDP
   session using the Extended Discovery mechanism described in [1,
   section 2.4-2.5], for this purpose a new type of FEC element is
   defined. The FEC element type is 128. [note1]

   The Virtual Circuit FEC element, is defined 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    VC tlv     |C|         VC Type             |VC info Length |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Group ID                                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        VC ID                                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Interface parameters                    |
   |                              "                                |
   |                              "                                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


     - VC Type

       A 15 bit quantity containing a value which represents the type of
       VC. Assigned Values are:

               VC Type  Description

               0x0001   Frame Relay DLCI
               0x0002   ATM AAL5 VCC transport
               0x0003   ATM transparent cell transport
               0x0004   Ethernet VLAN
               0x0005   Ethernet
               0x0006   HDLC ( Cisco )
               0x0007   PPP
               0x8008   CEM [8]
               0x0009   ATM VCC cell transport
               0x000A   ATM VPC cell transport
               0x000B   MPLS

     - Control word bit (C)

       The  highest  order bit (C) of the Vc type is used to flag the
       presence  of  a  control  word  ( defined in [7] ) as follows:



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               bit 15 = 1 control word present on this VC.
               bit 15 = 0 no control word present on this VC.

     - VC information length

       Length of the VC ID field and the interface parameters field in
       octets. If this value is 0, then it references all VCs using the
       specified group ID and there is no VC ID present, nor any
       interface parameters.

     - Group ID

       An arbitrary 32 bit value which represents a group of VCs that is
       used to augment the VC space. This value MUST be user
       configurable. The group ID is intended to be used as a port
       index, or a virtual tunnel index. To simplify configuration a
       particular VC ID at ingress could be part of the virtual tunnel
       for transport to the egress router. The Group ID is very useful
       to send a wild card label withdrawals to remote LSRs upon
       physical port failure.

     - VC ID

       A non zero 32-bit connection ID that together with the VC type,
       identifies a particular VC.

     - Interface parameters

       This variable length field is used to provide interface specific
       parameters, such as interface MTU.


5.1. Interface Parameters Field

   This field specifies edge facing interface specific parameters and
   SHOULD be used to validate that the LSRs, and the ingress and egress
   ports at the edges of the circuit have the necessary capabilities to
   interoperate with each other.  The field structure is defines 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Parameter ID |    Length     |    Variable Length Value      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                         Variable Length Value                 |
   |                             "                                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



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   The parameter ID is defined as follows:
   Parameter ID Length    Description

       0x01         4       Interface MTU in octets.
       0x02         4       Maximum Number of concatenated ATM cells.
       0x03   up to 82      Optional Interface Description string.
       0x04         4       CEM [8] Payload Bytes.
       0x05         4       CEM options.

   The Length field is defined as the length of the interface parameter
   including the parameter id and length field itself.

     - Interface MTU

       A 2 octet value indicating the MTU in bytes. This is the Maximum
       Transmit Unit of the egress packet interface that will be
       transmitting the decapsulated PDU that is received from the MPLS
       network. This parameter is REQUIRED, and SHOULD match in both
       direction of a specific circuit. The MTU is specified in bytes,
       and if it does not match on a specific circuit, that circuit
       should not be enabled. This parameter is applicable only to VC
       types 1, 2, 4, 5, 6, 7, and 0x0b.

     - Maximum Number of concatenated ATM cells

       This 2 octet parameter specifies the maximum number of
       concatenated ATM cells that can be processed as a single PDU by
       the egress LSR. This parameter does not need to match in both
       directions of a specific LSR. This parameter is REQUIRED for the
       following VC types: 3, 9, and 0x0a. An LSR transmitting
       concatenated cells on this VC can concatenate a number of cells
       up to the value of this parameter, but MUST NOT exceed it.

     - Optional Interface Description string

       This arbitrary, OPTIONAL,  interface description string can be
       used to send an administrative description text string to the
       remote LSR. This parameter is OPTIONAL, and is applicable to all
       VC types. The interface description parameter length is variable,
       and can be up to 80 octets.

     - Payload Bytes

       A 2 octet value indicating the the number of TDM payload octets
       contained in all packets on the CEM stream, from 48 to 1,023
       octets. All of the packets in a given CEM stream have the same
       number of payload bytes. Note that there is a possibility that
       the packet size may exceed the SPE size in the case of an STS-1



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       SPE, which could cause two pointers to be needed in the CEM
       header, since the payload may contain two J1 bytes for
       consecutive SPEs. For this reason, the number of payload bytes
       must be less than or equal to 783 for STS-1 SPEs.

     - CEM Options.  An optional 16 Bit value of CEM Flags. Bit 0 is
       defined being set to indicate CEM-DBA in operation.


6. IANA Considerations

   As specified in this document, a Virtual Circuit FEC element contains
   the VC Type field. VC Type value 0 is reserved. VC Type values 1
   through 11 are defined in this document. VC Type values 12 through 63
   are to be assigned by IANA using the "IETF Consensus" policy defined
   in RFC2434. VC Type values 64 through 127 are to be assigned by IANA,
   using the "First Come First Served" policy defined in RFC2434. VC
   Type values 128 through 32767 are vendor-specific, and values in this
   range are not to be assigned by IANA.

   As specified in this document, a Virtual Circuit FEC element contains
   the Interface Parameters field, which is a list of one or more
   parameters, and each parameter is identified by the Parameter ID
   field. Parameter ID value 0 is reserved. Parameter ID values 1
   through 5 are defined in this document.  Parameter ID values 6
   through 63 are to be assigned by IANA using the "IETF Consensus"
   policy defined in RFC2434. Parameter ID values 64 through 127 are to
   be assigned by IANA, using the "First Come First Served" policy
   defined in RFC2434. Parameter ID values 128 through 255 are vendor-
   specific, and values in this range are not to be assigned by IANA.


7. Security Considerations

   This document does not affect the underlying security issues of MPLS.

8. References

   [1] "LDP Specification." L. Andersson, P. Doolan, N. Feldman, A.
        Fredette, B. Thomas. January 2001. RFC3036

   [2] ITU-T Recommendation Q.933, and Q.922 Specification for Frame
   Mode Basic call control, ITU Geneva 1995

   [3] "MPLS Label Stack Encoding", E. Rosen, Y. Rekhter, D. Tappan, G.
        Fedorkow, D. Farinacci, T. Li, A. Conta. RFC3032

   [4] "IEEE 802.3ac-1998" IEEE standard specification.



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   [5] American National Standards Institute, "Synchronous Optical
   Network Formats," ANSI T1.105-1995.

   [6] ITU Recommendation G.707, "Network Node Interface For The
   Synchronous Digital Hierarchy", 1996.

   [7] "Encapsulation Methods for Transport of Layer 2 Frames Over
   MPLS", draft-martini-l2circuit-encap-mpls-01.txt ( Work in progress )

   [8] "SONET/SDH Circuit Emulation Service Over MPLS (CEM)
   Encapsulation", draft-malis-sonet-ces-mpls-01.txt ( Work in progress
   )

   [9] "Frame Based ATM over SONET/SDH Transport (FAST)," 2000.

   [note1] FEC element type 128 is pending IANA approval.

9. Author Information


   Luca Martini
   Level 3 Communications, LLC.
   1025 Eldorado Blvd.
   Broomfield, CO, 80021
   e-mail: luca@level3.net


   Nasser El-Aawar
   Level 3 Communications, LLC.
   1025 Eldorado Blvd.
   Broomfield, CO, 80021
   e-mail: nna@level3.net


   Giles Heron
   Level 3 Communications
   66 Prescot Street
   London
   E1 8HG
   United Kingdom
   e-mail: giles@level3.net


   Dimitri Stratton Vlachos
   Mazu Networks, Inc.
   125 Cambridgepark Drive
   Cambridge, MA 02140
   e-mail: d@mazunetworks.com



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   Dan Tappan
   Cisco Systems, Inc.
   250 Apollo Drive
   Chelmsford, MA, 01824
   e-mail: tappan@cisco.com


   Jayakumar Jayakumar,
   Cisco Systems Inc.
   225, E.Tasman, MS-SJ3/3,
   San Jose, CA, 95134
   e-mail: jjayakum@cisco.com


   Alex Hamilton,
   Cisco Systems Inc.
   285 W. Tasman, MS-SJCI/3/4,
   San Jose, CA, 95134
   e-mail: tahamilt@cisco.com


   Eric Rosen
   Cisco Systems, Inc.
   250 Apollo Drive
   Chelmsford, MA, 01824
   e-mail: erosen@cisco.com


   Steve Vogelsang
   Laurel Networks, Inc.
   2607 Nicholson Rd.
   Sewickley, PA 15143
   e-mail: sjv@laurelnetworks.com


   John Shirron
   Laurel Networks, Inc.
   2607 Nicholson Rd.
   Sewickley, PA 15143
   e-mail: jshirron@laurelnetworks.com










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   Andrew G. Malis
   Vivace Networks, Inc.
   2730 Orchard Parkway
   San Jose, CA 95134
   Phone: +1 408 383 7223
   Email: Andy.Malis@vivacenetworks.com


   Vinai Sirkay
   Vivace Networks, Inc.
   2730 Orchard Parkway
   San Jose, CA 95134
   e-mail: vinai.sirkay@vivacenetworks.com





































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