CCAMP Working Group                   Eric Mannie (Ebone) - Editor
   Internet Draft
   Expiration Date: June 2002                Stefan Ansorge (Alcatel)
                                         Peter Ashwood-Smith (Nortel)
                                              Ayan Banerjee (Calient)
                                                   Lou Berger (Movaz)
                                               Greg Bernstein (Ciena)
                                                 Angela Chiu (Celion)
                                                 John Drake (Calient)
                                                 Yanhe Fan (Axiowave)
                                            Michele Fontana (Alcatel)
                                               Gert Grammel (Alcatel)
                                              Juergen Heiles(Siemens)
                                               Suresh Katukam (Cisco)
                                           Kireeti Kompella (Juniper)
                                           Jonathan P. Lang (Calient)
                                                  Fong Liaw (Zaffire)
                                                 Zhi-Wei Lin (Lucent)
                                             Ben Mack-Crane (Tellabs)
                                      Dimitri Papadimitriou (Alcatel)
                                       Dimitrios Pendarakis (Tellium)
                                           Mike Raftelis (White Rock)
                                           Bala Rajagopalan (Tellium)
                                              Yakov Rekhter (Juniper)
                                              Debanjan Saha (Tellium)
                                             Vishal Sharma (Metanoia)
                                               George Swallow (Cisco)
                                                 Z. Bo Tang (Tellium)
                                                   Eve Varma (Lucent)
                                             Maarten Vissers (Lucent)
                                                Yangguang Xu (Lucent)

                                                        December 2001


    GMPLS Extensions to Control Non-Standard SONET and SDH Features


         draft-ietf-ccamp-gmpls-sonet-sdh-extensions-01.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."

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  draft-ietf-ccamp-gmpls-sonet-sdh-extensions-01.txt  December, 2001


   To view the current status of any Internet-Draft, please check the
   "1id-abstracts.txt" listing contained in an Internet-Drafts Shadow
   Directory, see http://www.ietf.org/shadow.html.


Abstract

   This document is a companion to the GMPLS signaling extensions to
   control SONET and SDH document [GMPLS-SONET-SDH] that defines the
   SONET/SDH technology specific information needed when using GMPLS
   signaling.

   This informational document defines GMPLS signaling extensions to
   control four optional non-standard (i.e. proprietary) SONET and
   SDH features: group signals, arbitrary concatenation, virtual
   concatenation of contiguously concatenated signals and per byte
   transparency.


1. Introduction

   Generalized MPLS (GMPLS) [GMPLS-ARCH] extends MPLS from supporting
   packet (Packet Switching Capable - PSC) interfaces and switching
   to include support of four new classes of interfaces and
   switching: Layer-2 Switch Capable (L2SC), Time-Division Multiplex
   (TDM), Lambda Switch Capable (LSC) and Fiber-Switch Capable (FSC).

   A functional description of the extensions to MPLS signaling
   needed to support the new classes of interfaces and switching is
   provided in [GMPLS-SIG]. [GMPLS-RSVP] describes RSVP-TE specific
   formats and mechanisms needed to support all five classes of
   interfaces, and CR-LDP extensions can be found in [GMPLS-LDP].

   [GMPLS-SONET-SDH] presents details that are specific to SONET/SDH.
   Per [GMPLS-SIG], SONET/SDH specific parameters are carried in the
   signaling protocol in traffic parameter specific objects.

   This informational document defines GMPLS signaling extensions to
   control four optional non-standard (i.e. proprietary) SONET/SDH
   features: group signals (section 2), arbitrary concatenation
   (section 3), virtual concatenation of contiguously concatenated
   signals (section 4), and per byte transparency (section 5).
   Section 6 gives examples of SONET/SDH traffic parameters (also
   referred to as signal coding) when requesting a SONET/SDH LSP.

   Such features are already implemented or under development by a
   significant number of manufacturers. For instance, arbitrary
   concatenation is already implemented in many legacy SONET and SDH
   equipment that don't support any byte-oriented protocol based
   control plane.




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   This document doesn't specify how to implement these features in
   the transmission plane but how to control their usage with a GMPLS
   control plane.

   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 [RFC2119].


2. Signal Type Values Extension For Group Signals

   This section defines the following optional additional Signal Type
   values for the Signal Type field of section 2.1 of [GMPLS-SONET-
   SDH]:

       Value         Type
       -----  ---------------------
        13     VTG      / TUG-2
        14                TUG-3
        15     STSG-3   / AUG-1
        16     STSG-12  / AUG-4
        17     STSG-48  / AUG-16
        18     STSG-192 / AUG-64
        19     STSG-768 / AUG-256

  Administrative Unit Group-Ns (AUG-Ns) and STS Groups-3*Ns (STSG-Ms),
  are logical objects defined as a collection of AU-3s/STS-1 SPEs, AU-
  4s/STS-3c SPEs and/or AU-4-Xcs/STS-3*Xc SPEs (X = 4,16,64,256).

  When used as a signal type this means that all the VC-3s/STS-1_SPEs,
  VC-4s/STS-3c_SPEs or VC-4-Xcs/STS-3*Xc SPEs in the AU-3s/STS-1 SPEs,
  AU-4s/STS-3c SPEs or AU-4-Xcs/STS-3*Xc SPEs that comprise the AUG-
  N/STSG-3*N are switched together as one unique signal.

  In addition the structure of the VC-3s/STS-1_SPEs, VC-4s/STS-3c_SPEs
  and VC-4-Xcs/STS-3*Xc_SPEs in the AUG-N/STSG-3*N are preserved and
  are allowed to change over the life of an AUG-N/STSG-3*N.

  It is this flexibility in the relationships between the component VCs
  or SPEs that differentiates this signal from a set of VC-3s/STS-
  1_SPEs, VC-4s/STS-3c_SPEs or VC-4-Xcs/STS-3*Xc_SPEs. Whether the AUG-
  N/STSG-3*N is structured with AU-3s/STS-1 SPEs, AU-4s/STS-3c SPEs
  and/or AU-4-Xcs/STS-3*Xc SPEs does not need to be specified and is
  allowed to change over time. The same reasoning applies to TUG-2/VTG
  and TUG-3 signal types.

  For example an STSG-48 could at one time consist of four STS-12c
  signals and at another point in time of three STS-12c signals and
  four STS-3c signals.

  Note that the use of VTG, TUG-X, AUG-N and STSG-M as circuit types is
  not described in ANSI and ITU-T standards. These signal types are
  conceptual objects that intend to designate a group of physical
  objects in the data plane.

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3. Contiguous Concatenation Extension

   This section defines the following optional extension flag for the
   Requested Contiguous Concatenation (RCC) field defined in section
   2.1 of [GMPLS-SONET-SDH]:

      Flag 2 (bit 2): Arbitrary contiguous concatenation.

   This flag allows an upstream node to signal to a downstream node
   that it supports arbitrary contiguous concatenation. This type of
   concatenation is not defined by ANSI or ITU-T.

   Arbitrary contiguous concatenation allows the contiguous
   concatenation of any number X of VC-4/STS-1 SPE/STS-3c SPE with X
   less or equal N, resulting in a VC-4-Xa/STS-1-Xa SPE/STS-3c-Xa SPE
   signal. In addition, it allows the arbitrary contiguous
   concatenated signal to start at any location (AU-4/STS-1 timeslot)
   in the STM-N/STS-N signal.

   This flag can be setup together with Flag 1 (Standard Contiguous
   Concatenation) to give a choice to the downstream node. The
   resulting type of contiguous concatenation can be different at
   each hop according to the result of the negotiation.

   A label is assigned following the same rule as for the Standard
   Contiguous Concatenation (see [GMPLS-SONET-SDH]).


4. Virtual Concatenation Extension

   This section defines the following optional extension for the
   signals that can be virtually concatenated.

   In addition to the elementary signal types, which can be virtual
   concatenated as described in section 2.1 of [GMPLS-SONET-SDH],
   identical contiguously concatenated signals may be virtually
   concatenated. In this last case, it allows for instance to request
   the virtual concatenation of several VC-4-4c/STS-12c SPEs (i.e.
   per [GMPLS-SONET-SDH] (STS-3c)-4c SPE), or more generally any VC-
   4-Xc/STS-3c-Xc SPEs to obtain a VC-4-Xc-Yv/STS-3c-Xc-Yv.

   The virtual concatenation can also be applied to arbitrary
   contiguously concatenated signals to form VC-4-Xa-Yv/STS-1-Xa-Yv
   SPE/STS-3c-Xa-Yv SPE. Note that STS-3c-Xa-Yv SPE signal is
   described only for completeness of the mechanism defined in this
   document.

   The standard definition for virtual concatenation allows each
   virtual concatenation components to travel over diverse paths.
   Within GMPLS, virtual concatenation components must travel over
   the same (component) link if they are part of the same LSP. This
   is due to the way that labels are bound to a (component) link.

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   Note however, that the routing of components on different paths is
   indeed equivalent to establishing different LSPs, each one having
   its own route. Several LSPs can be initiated and terminated
   between the same nodes and their corresponding components can then
   be associated together (i.e. virtually concatenated).

   In case of virtual concatenation of a contiguously concatenated
   signal, the same rule as described in section 3 of [GMPLS-SONET-
   SD] for virtual concatenation applies, except that a component of
   the virtually concatenated signal is now a contiguously
   concatenated signal. The first label indicates the first
   contiguously concatenated signal; the second label indicates the
   second contiguously concatenated signal, and so on.


5. Transparency Extension

   This section defines the following optional extension for the
   Transparency field defined in section 2.1 of [GMPLS-SONET-SDH].

  This "extended" transparency (simply referred here as
  transparency) can be requested for a particular SOH/RSOH or
  MSOH/LOH field in the STM-N/STS-N signal.

  Transparency is not applied at the interfaces of the initiating
  and terminating LSRs, but is only applied between intermediate
  LSRs. Moreover, the transparency extensions can be implemented
  effectively in very different ways, e.g. by forwarding the
  corresponding overhead bytes unmodified, or by tunneling the
  bytes.

  This document specifies neither how transparency is achieved; nor
  the behavior of the signal at the egress of the transparent
  network during fault conditions at the ingress of the transparent
  network or within the transparent network; nor network deployment
  scenarios. The signaling is independent of these considerations.

  When the signaling is used between intermediate nodes it is up to
  a data plane profile or specification to indicate how transparency
  is effectively achieved in the data plane. When the signaling is
  used at the interfaces with the initiating and terminating LSRs it
  is up to the data plane specification to guarantee compliant
  behavior to G.707/T1.105 under fault free and fault conditions.

  Note that B1 in the SOH/RSOH is computed over the complete
  previous frame, if one bit changes, B1 must be re-computed. Note
  that B2 in the LOH/MSOH is also computed over the complete
  previous frame, except the SOH/RSOH.







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  draft-ietf-ccamp-gmpls-sonet-sdh-extensions-01.txt  December, 2001

  The different transparency extension flags are the following:

       Flag 3  (bit 3) : J0.
       Flag 4  (bit 4) : SOH/RSOH DCC (D1-D3).
       Flag 5  (bit 5) : LOH/MSOH DCC (D4-D12).
       Flag 6  (bit 6) : LOH/MSOH Extended DCC (D13-D156).
       Flag 7  (bit 7) : K1/K2.
       Flag 8  (bit 8) : E1.
       Flag 9  (bit 9) : F1.
       Flag 10 (bit 10): E2.
       Flag 11 (bit 11): B1.
       Flag 12 (bit 12): B2.
       Flag 13 (bit 13): M0.
       Flag 14 (bit 14): M1.

  Line/Multiplex Section layer transparency (refer to section 2.1 of
  [GMPLS-SONET-SDH]) can be combined only with any of the following
  transparency types: J0, SOH/RSOH DCC (D1-D3), E1, F1; and all
  other transparency flags must be ignored.

  Note that the extended LOH/MSOH DCC (D13-D156) is only applicable
  to (defined for) STS-768/STM-256.

   If B1 transparency is requested, this means transparency for the bit
   error supervision functionality provided by the B1. The B1 contains
   the BIP8 calculated over the previous RS/Section frame of the STM-
   N/STS-N signal at the RS/Section termination source. At the
   RS/Section termination sink the B1 BIP is compared with the local
   BIP also calculated over the previous RS/Section frame of the STM-
   N/STS-N. Any difference between the two BIP values is an indication
   for a bit error that occurred between the termination source and
   sink. In case of B1 transparency this functionality shall be
   preserved. This means that a B1 bit error detection as described
   above performed after the transparent transport (at a RS/Section
   termination sink) indicates exactly the bit errors that occur
   between the B1 insertion point (RS/Section termination source) and
   this point. Any intended changes to the previous RS/Section frame
   content due to the implementation of the transparency feature (e.g.
   modifications of the RS/Section overhead, modifications of the
   payload due to pointer justifications) have to be reflected in the
   B1 BIP value, it has to be adjusted accordingly.

   If B2 transparency is requested, this means transparency for the bit
   error supervision functionality provided by the B2. The B2 contains
   the BIP24*N/BIP8*N calculated over the previous MS/Line frame of the
   STM-N/STS-N signal at the MS/Line termination source. At the MS/Line
   termination sink the B2 BIP is compared with the local BIP also
   calculated over the previous MS/Line frame of the STM-N/STS-N. Any
   difference between the two BIP values is an indication for a bit
   error that occurred between the termination source and sink. In case
   of B2 transparency this functionality shall be preserved. This means
   that a B2 bit error detection as described above performed after the
   transparent transport (at a MS/Line termination sink) indicates
   exactly the bit errors that occur between the B2 insertion point

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  draft-ietf-ccamp-gmpls-sonet-sdh-extensions-01.txt  December, 2001

   (MS/Line termination source) and this point. Any intended changes to
   the previous MS/Line frame content due to the implementation of the
   transparency feature (e.g. modifications of the MS/Line overhead,
   modifications of the payload due to pointer justifications) have to
   be reflected in the B2 BIP value, it has to be adjusted accordingly.

   M1 and M1/M0 transparency are only meaningful when the B2
   transparency is requested.


6. Examples

   This section defines examples of SONET and SDH signal coding. Their
   objective is to help the reader to understand how works the traffic
   parameter coding and not to give examples of typical SONET or SDH
   signals.

   As stated in [GMPLS_SONET_SDH], signal types are Elementary
   Signals to which successive concatenation, multiplication and
   transparency transforms can be applied.

   1. An STM-64 signal with RSOH and MSOH DCCs transparency is formed
   by the application of RCC with value 0, NCC with value 0, NVC with
   value 0, MT with value 1 and T with flag 4 and 5 to an STM-64
   Elementary Signal.

   2. An STS-192 signal with K1/K2 and LOH DCC transparency is formed
   by the application of RCC with value 0, NVC with value 0, MT with
   value 1 and T with flags 5 and 7 to an STS-192 Elementary Signal.

   3. An STS-48c signal with LOH DCC and E2 transparency is formed by
   the application of RCC with flag 1, NCC with value 1, NVC with
   value 0, MT with value 1 and T with flag 5 and 10 to an STS-48
   Elementary Signal.

   4. An STS-768c signal with K1/K2 and LOH DCC transparency is
   formed by the application of RCC with flag 1, NCC with value 1,
   NVC with value 0, MT with value 1 and T with flag 5 and 7 to an
   STS-768 Elementary Signal.

   5. 4 x STS-12 signals with K1/K2 and LOH DCC transparency is
   formed by the application of RCC with value 0, NVC with value 0,
   MT with value 4 and T with flags 5 and 7 to an STS-12 Elementary
   Signal.

   6. A VC-4-3a signal is formed by the application of RCC with flag
   2 (arbitrary contiguous concatenation), NCC with value 3, NVC with
   value 0, MT with value 1 and T with value 0 to a VC-4 Elementary
   Signal.

   7. An STS-1-34a SPE signal is formed by the application of RCC
   with flag 2 (arbitrary contiguous concatenation), NCC with value
   34, NVC with value 0, MT with value 1 and T with value 0 to an
   STS-1 SPE Elementary Signal.

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  draft-ietf-ccamp-gmpls-sonet-sdh-extensions-01.txt  December, 2001


   8. 2 x STS-1-4a-5v SPE signal is formed by the application of RCC
   with flag 2 (for arbitrary contiguous concatenation), NCC with
   value 4, NVC with value 5, MT with value 2 and T with value 0 to
   an STS-1 SPE Elementary Signal.


7. Acknowledgments

   Valuable comments and input were received from many people.


8. Security Considerations

   This draft introduces no new security considerations to [GMPLS-
   SONET-SDH].


9. References

   [GMPLS-SIG] Ashwood-Smith, P. et al, "Generalized MPLS -
               Signaling Functional Description", Internet Draft,
               draft-ietf-mpls-generalized-signaling-07.txt,
               November 2001.

   [GMPLS-LDP] Ashwood-Smith, P. et al, "Generalized MPLS Signaling -
               CR-LDP Extensions", Internet Draft,
               draft-ietf-mpls-generalized-cr-ldp-05.txt,
               November 2001.

   [GMPLS-RSVP] Ashwood-Smith, P. et al, "Generalized MPLS
                Signaling - RSVP-TE Extensions", Internet Draft,
                draft-ietf-mpls-generalized-rsvp-te-06.txt,
                November 2001.

   [GMPLS-SONET-SDH] E. Mannie Editor, "GMPLS extensions for SONET
                and SDH control", Internet Draft,
                draft-ietf-ccamp-gmpls-sonet-sdh-03.txt, December
                2001.

   [GMPLS-ARCH] E. Mannie Editor, "GMPLS Architecture", Internet
                Draft, draft-ietf-ccamp-gmpls-architecture-01.txt,
                November 2001.

   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels," RFC 2119.









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10. Authors Addresses

      Stefan Ansorge
      Alcatel
      Lorenzstrasse 10
      70435 Stuttgart
      Germany
      Phone: +49 7 11 821 337 44
      Email: Stefan.ansorge@alcatel.de

      Peter Ashwood-Smith
      Nortel Networks Corp.
      P.O. Box 3511 Station C,
      Ottawa, ON K1Y 4H7
      Canada
      Phone:  +1 613 763 4534
      Email:  petera@nortelnetworks.com

      Ayan Banerjee
      Calient Networks
      5853 Rue Ferrari
      San Jose, CA 95138
      Phone:  +1 408 972-3645
      Email:  abanerjee@calient.net

      Lou Berger
      Movaz Networks, Inc.
      7926 Jones Branch Drive
      Suite 615
      McLean VA, 22102
      Phone:  +1 703 847-1801
      Email:  lberger@movaz.com

      Greg Bernstein
      Ciena Corporation
      10480 Ridgeview Court
      Cupertino, CA 94014
      Phone:  +1 408 366 4713
      Email:  greg@ciena.com

      Angela Chiu
      Celion Networks
      One Sheila Drive, Suite 2
      Tinton Falls, NJ 07724-2658
      Phone: +1 732 747 9987
      Email: angela.chiu@celion.com

      John Drake
      Calient Networks
      5853 Rue Ferrari
      San Jose, CA 95138
      Phone:  +1 408 972 3720
      Email:  jdrake@calient.net


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      Yanhe Fan
      Axiowave Networks, Inc.
      100 Nickerson Road
      Marlborough, MA 01752
      Phone:  +1 508 460 6969 Ext. 627
      Email:  yfan@axiowave.com

      Michele Fontana
      Alcatel
      Via Trento 30,
      I-20059 Vimercate, Italy
      Phone: +39 039 686-7053
      Email: michele.fontana@netit.alcatel.it

      Gert Grammel
      Alcatel
      Via Trento 30,
      I-20059 Vimercate, Italy
      Phone: +39 039 686-7060
      Email: gert.grammel@netit.alcatel.it

      Juergen Heiles
      Siemens AG
      Hofmannstr. 51
      D-81379 Munich, Germany
      Phone: +49 89 7 22 - 4 86 64
      Email: Juergen.Heiles@icn.siemens.de

      Suresh Katukam
      Cisco Systems
      1450 N. McDowell Blvd,
      Petaluma, CA 94954-6515 USA
      e-mail: skatukam@cisco.com

      Kireeti Kompella
      Juniper Networks, Inc.
      1194 N. Mathilda Ave.
      Sunnyvale, CA 94089
      Email:  kireeti@juniper.net

      Jonathan P. Lang
      Calient Networks
      25 Castilian
      Goleta, CA 93117
      Email:  jplang@calient.net

      Zhi-Wei Lin
      101 Crawfords Corner Rd
      Holmdel, NJ  07733-3030
      Phone: +1 732 949 5141
      Email: zwlin@lucent.com




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  draft-ietf-ccamp-gmpls-sonet-sdh-extensions-01.txt  December, 2001

      Ben Mack-Crane
      Tellabs
      Email: Ben.Mack-Crane@tellabs.com

      Eric Mannie
      EBONE
      Terhulpsesteenweg 6A
      1560 Hoeilaart - Belgium
      Phone:  +32 2 658 56 52
      Mobile: +32 496 58 56 52
      Fax:    +32 2 658 51 18
      Email:  eric.mannie@ebone.com

      Dimitri Papadimitriou
      Alcatel
      Francis Wellesplein 1,
      B-2018 Antwerpen, Belgium
      Phone: +32 3 240-8491
      Email: Dimitri.Papadimitriou@alcatel.be

      Mike Raftelis
      White Rock Networks
      18111 Preston Road Suite 900
      Dallas, TX 75252
      Phone: +1 (972)588-3728
      Fax:   +1 (972)588-3701
      Email: Mraftelis@WhiteRockNetworks.com

      Bala Rajagopalan
      Tellium, Inc.
      2 Crescent Place
      P.O. Box 901
      Oceanport, NJ 07757-0901
      Phone:  +1 732 923 4237
      Fax:    +1 732 923 9804
      Email:  braja@tellium.com

      Yakov Rekhter
      Juniper Networks, Inc.
      Email:  yakov@juniper.net

      Debanjan Saha
      Tellium Optical Systems
      2 Crescent Place
      Oceanport, NJ 07757-0901
      Phone:  +1 732 923 4264
      Fax:    +1 732 923 9804
      Email:  dsaha@tellium.com







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      Vishal Sharma
      Metanoia, Inc.
      335 Elan Village Lane
      San Jose, CA 95134
      Phone:  +1 408 943 1794
      Email: vsharma87@yahoo.com

      George Swallow
      Cisco Systems, Inc.
      250 Apollo Drive
      Chelmsford, MA 01824
      Voice:  +1 978 244 8143
      Email:  swallow@cisco.com

      Z. Bo Tang
      Tellium, Inc.
      2 Crescent Place
      P.O. Box 901
      Oceanport, NJ 07757-0901
      Phone:  +1 732 923 4231
      Fax:    +1 732 923 9804
      Email:  btang@tellium.com

      Eve Varma
      101 Crawfords Corner Rd
      Holmdel, NJ  07733-3030
      Phone: +1 732 949 8559
      Email: evarma@lucent.com

      Maarten Vissers
      Botterstraat 45
      Postbus 18
      1270 AA Huizen, Netherlands
      Email: mvissers@lucent.com

      Yangguang Xu
      21-2A41, 1600 Osgood Street
      North Andover, MA 01845
      Email: xuyg@lucent.com
















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