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   CCAMP Working Group                   Eric Mannie (Ebone) - Editor
   Internet Draft
   Expiration Date: December 2001            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)

                                                           June 2001


               GMPLS Extensions for SONET and SDH Control


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


E. Mannie Editor                                                     1

               draft-ietf-ccamp-gmpls-sonet-sdh-01.txt     June, 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 Generalized MPLS signaling
   documents, [GMPLS-SIG], [GMPLS-RSVP] and [GMPLS-LDP].  It defines
   the SONET/SDH technology specific information needed when using
   GMPLS signaling.


1. Introduction

   Generalized MPLS (GMPLS) extends MPLS from supporting packet
   (Packet Switching Capable - PSC) interfaces and switching to
   include support of three new classes of interfaces and switching:
   Time-Division Multiplex (TDM), Lambda Switch (LSC) and Fiber-
   Switch (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 four
   classes of interfaces, and CR-LDP extensions can be found in
   [GMPLS-LDP]. This document 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.

   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. SDH and SONET Traffic Parameters

   This section defines the GMPLS traffic parameters for SONET/SDH.
   The protocol specific formats, for the SDH/SONET-specific RSVP-TE
   objects and CR-LDP TLVs are described in sections 2.2 and 2.3
   respectively.

   These traffic parameters specify indeed a base set of capabilities
   for SONET (ANSI T1.105) and SDH (ITU-T G.707) such as
   concatenation and transparency. Other documents could enhance this
   set of capabilities in the future. For instance, signaling for SDH
   over PDH (ITU-T G.832), or sub-STM-0 (ITU-T G.708) interfaces
   could be defined.

   The traffic parameters defined hereafter MUST be used when
   SONET/SDH is specified in the LSP Encoding Type field of a
   Generalized Label Request [GMPLS-SIG].




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

2.1. SONET/SDH Traffic Parameters

      The traffic parameters for SONET/SDH is organized 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Signal Type  |      RCC      |              NCC              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |              NVC              |        Multiplier (MT)        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Transparency (T)                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Signal Type (ST): 8 bits

     This field indicates the type of Elementary Signal that
     comprises the requested LSP. Several transforms can be applied
     successively on the Elementary Signal to build the Final Signal
     being actually requested for the LSP.

     Each transform is optional and must be ignored if zero, except
     MT that cannot be zero and is ignored if equal to one.

     Transforms must be applied strictly in the following order:

      - First, contiguous concatenation (by using the RCC and NCC
        fields) can be optionally applied on the Elementary Signal,
        resulting in a contiguously concatenated signal.
      - Second, virtual concatenation (by using the NVC field) can
        be optionally applied either directly on the Elementary
        Signal, or on the contiguously concatenated signal obtained
        from the previous phase (see Appendix 4).
      - Third, some transparency can be optionally specified when
        requesting a frame as signal rather than an SPE or VC based
        signal (by using the Transparency field).
      - Fourth, a multiplication (by using the Multiplier field) can be
        optionally applied either directly on the Elementary Signal, or
        on the contiguously concatenated signal obtained from the first
        phase, or on the virtually concatenated signal obtained from
        the second phase, or on these signals combined with some
        transparency.













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

   Permitted Signal Type values for SONET/SDH are:

       Value      Type
       -----  -----------------
        1    VT1.5  SPE / VC-11
        2    VT2    SPE / VC-12
        3    VT3    SPE
        4    VT6    SPE / VC-2
        5    STS-1  SPE / VC-3
        6    STS-3c SPE / VC-4
        7    STS-1      / STM-0   (only when requesting transparency)
        8    STS-3      / STM-1   (only when requesting transparency)
        9    STS-12     / STM-4   (only when requesting transparency)
        10   STS-48     / STM-16  (only when requesting transparency)
        11   STS-192    / STM-64  (only when requesting transparency)
        12   STS-768    / STM-256 (only when requesting transparency)

     A dedicated signal type is assigned to a SONET STS-3c SPE instead
     of coding it as a contiguous concatenation of three STS-1 SPEs.
     This was done in order to provide easy interworking between SONET
     and SDH signaling.

     Refer to Appendix 1 and Appendix 2 for an extended set of signal
     type values beyond the signal types as defined in T1.105/G.707.

   Requested Contiguous Concatenation (RCC): 8 bits

     This field is used to request and negotiate the optional
     SONET/SDH contiguous concatenation of the Elementary Signal.

     This field is a vector of flags. Each flag indicates the
     support of a particular type of contiguous concatenation.
     Several flags can be set at the same time to indicate a choice.

     These flags allow an upstream node to indicate to a downstream
     node the different types of contiguous concatenation that it
     supports. However, the downstream node decides which one to use
     according to its own rules.

     A downstream node receiving such flags chooses, as it likes, a
     particular type of contiguous concatenation, if any supported.
     A downstream node that doesnÆt support any of the concatenation
     types indicated by the field must refuse the LSP request. In
     particular, it must refuse the LSP request if it doesnÆt
     support contiguous concatenation at all.

     The upstream node can know which type of contiguous
     concatenation the downstream node chosen by looking at the
     position indicated by the first label and the number of
     label(s) as returned by the downstream node.





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     The entire field is set to zero to indicate that no contiguous
     concatenation is requested at all (default value). A non-zero
     field indicates that some contiguous concatenation is being
     requested.

     The following flag is defined:

         Flag 1 (bit 1): Standard contiguous concatenation.

     Flag 1 indicates that only the standard SONET/SDH contiguous
     concatenation as defined in T1.105/G.707 is supported. Note
     that bit 1 is the low order bit. Other flags are reserved for
     extensions, if not used they should be set to zero when sent,
     and should be ignored when received.

     See note 1 hereafter in the section on the NCC about the SONET
     contiguous concatenation of STS-1 SPEs when the number of
     components is a multiple of three.

     Refer to Appendix 3 for an extended set of contiguous
     concatenation types beyond the contiguous concatenation types as
     defined in T1.105/G.707.

   Number of Contiguous Components (NCC): 16 bits

     This field indicates the number of identical SONET/SDH SPEs/VCs
     that are requested to be concatenated, as specified in the RCC
     field.

     Note 1: when requesting a SONET STS-Nc SPE with N=3*X, the
     elementary signal to use must always be an STS-3c SPE signal
     type and the value of NCC must always be equal to X. This
     allows also facilitating the interworking between SONET and
     SDH. In particular, it means that the contiguous concatenation
     of three STS-1 SPEs cannot not be requested because according
     to this specification, this type of signal must be coded using
     the STS-3c SPE signal type.

     Note 2: when requesting a transparent STM-N/STS-N signal
     limited to a single contiguously concatenated VC-4-Nc/STS-Nc-
     SPE, the signal type must be STM-N/STS-N, RCC with flag 1 and
     NCC set to 1.

     This field is irrelevant if no contiguous concatenation is
     requested (RCC = 0), in that case it must be set to zero when
     send, and should be ignored when received. A RCC value
     different from 0 must imply a number of components greater than
     1.







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

   Number of Virtual Components (NVC): 16 bits

     This field indicates the number of signals that are requested
     to be virtually concatenated. These signals are all of the same
     type by definition. They are Elementary Signal SPEs/VCs for
     which signal types are defined.

     This field is set to 0 (default value) to indicate that no
     virtual concatenation is requested.

     Refer to Appendix 4 for an extended set of signals that can be
     virtually concatenated beyond the virtual concatenation as defined
     in T1.105/G.707.

   Multiplier (MT): 16 bits

     This field indicates the number of identical signals that are
     requested for the LSP, i.e. that form the Final Signal. These
     signals can be either identical Elementary Signals, or
     identical contiguously concatenated signals, or identical
     virtually concatenated signals. Note that all these signals
     belongs thus to the same LSP.

     The distinction between the components of multiple virtually
     concatenated signals is done via the order of the labels that
     are specified in the signaling. The first set of labels must
     describe the first component (set of individual signals
     belonging to the first virtual concatenated signal), the second
     set must describe the second component (set of individual
     signals belonging to the second virtual concatenated signal)
     and so on.

     This field is set to one (default value) to indicate that
     exactly one instance of a signal is being requested. Zero is an
     invalid value.

   Transparency (T): 32 bits

     This field is a vector of flags that indicates the type of
     transparency being requested. Several flags can be combined to
     provide different types of transparency. Not all combinations
     are necessarily valid. The default value for this field is
     zero, i.e. no transparency requested.

     Transparency as defined from the point of view of this
     signaling specification is only applicable to the fields in the
     SONET/SDH frame overheads. In the SONET case, these are the
     fields in the Section Overhead (SOH), and the Line Overhead
     (LOH). In the SDH case, these are the fields in the Regenerator
     Section Overhead (RSOH), the Multiplex Section overhead (MSOH),
     and the pointer fields between the two. With SONET, the pointer
     fields are part of the LOH.



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

     Note as well that transparency is only applicable when using
     the following Signal Types: STM-0, STM-1, STM-4, STM-16, STM-
     64, STM-256, STS-1, STS-3, STS-12, STS-48, STS-192, and STS-
     768. At least one transparency type must be specified when
     requesting such a signal type.

     Transparency indicates precisely which fields in these
     overheads must be delivered unmodified at the other end of the
     LSP. An ingress LSR requesting transparency will pass these
     overhead fields that must be delivered to the egress LSR
     without any change. From the ingress and egress LSRs point of
     views, these fields must be seen as unmodified.

     Transparency is not applied at the interfaces with the
     initiating and terminating LSRs, but is only applied between
     intermediate LSRs.

     The transparency field is used to request an LSP that supports
     the requested transparency type; it may also be used to setup
     the transparency process to be applied in each intermediate
     LSR.

     The different transparency flags are the following:

        Flag 1 (bit 1): Section/Regenerator Section layer.
        Flag 2 (bit 2): Line/Multiplex Section layer.

     Where bit 1 is the low order bit. Others flags are reserved,
     they should be set to zero when sent, and should be ignored
     when received. A flag is set to one to indicate that the
     corresponding transparency is requested.

     Section/Regenerator Section layer transparency means that the
     entire frames must be delivered unmodified. This implies that
     pointers cannot be adjusted. When using Section/Regenerator
     Section layer transparency all other flags must be ignored.

     Line/Multiplex Section layer transparency means that the
     LOH/MSOH must be delivered unmodified. This implies that
     pointers cannot be adjusted.

     Refer to Appendix 5 for an extended set of transparency types
     beyond the transparency types as defined in T1.105/G.707.

2.2. RSVP-TE Details

   For RSVP-TE, the SONET/SDH traffic parameters are carried in the
   SONET/SDH SENDER_TSPEC and FLOWSPEC objects.  The same format is
   used both for SENDER_TSPEC object and FLOWSPEC objects. The
   contents of the objects is defined above in Section 2.1. The
   objects have the following class and type:




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     For SONET ANSI T1.105 and SDH ITU-T G.707:

       SONET/SDH SENDER_TSPEC object: Class = 12, C-Type = 4 (TBA)
       SONET/SDH FLOWSPEC object: Class = 9, C-Type = 4 (TBA)

   There is no Adspec associated with the SONET/SDH SENDER_TSPEC.
   Either the Adspec is omitted or an int-serv Adspec with the
   Default General Characterization Parameters and Guaranteed Service
   fragment is used, see [RFC2210].

   For a particular sender in a session the contents of the FLOWSPEC
   object received in a Resv message SHOULD be identical to the
   contents of the SENDER_TSPEC object received in the corresponding
   Path message. If the objects do not match, a ResvErr message with
   a "Traffic Control Error/Bad Flowspec value" error SHOULD be
   generated.

2.3. CR-LDP Details


   For CR-LDP, the SONET/SDH traffic parameters are carried in the
   SONET/SDH Traffic Parameters TLV.  The contents of the TLV is
   defined above in Section 2.1. The header of the TLV has the
   following format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |U|F|          Type             |      Length                   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     The type field indicates either SONET or SDH:

       For SONET ANSI T1.105 : 0xTBA.
       For SDH ITU-T G.707   : 0xTBA.


3. SDH and SONET Labels

   SDH and SONET each define a multiplexing structure, with the SONET
   multiplex structure being a subset of the SDH multiplex structure.
   These two structures are trees whose roots are respectively an
   STM-N or an STS-N; and whose leaves are the signals that can be
   transported via the time-slots and switched between time-slots,
   i.e. a VC-x or a VT-x. An SDH/SONET label will identify the exact
   position of a particular signal in a multiplexing structure. SDH
   and SONET labels are carried in the Generalized Label per [GMPLS-
   RSVP] and [GMPLS-LDP].

   These multiplexing structures will be used as naming trees to
   create unique multiplex entry names or labels. Since the SONET
   multiplexing structure may be seen as a subset of the SDH
   multiplexing structure, the same format of label is used for SDH
   and SONET. As explained in [GMPLS-SIG], a label does not identify

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   the "class" to which the label belongs. This is implicitly
   determined by the link on which the label is used. However, in
   some cases the encoding specified hereafter can make the direct
   distinction between SDH and SONET.

   In case of signal concatenation or multiplication, a list of
   labels can appear in the Label field of a Generalized Label.

   In case of any type of contiguous concatenation, only one label
   appears in the Label field. That label is the lowest signal of the
   contiguously concatenated signal. By lowest signal we mean the one
   having the lowest label when compared as integer values, i.e. the
   first component signal of the concatenated signal encountered when
   descending the tree.

   In case of virtual concatenation, the explicit ordered list of all
   labels in the concatenation is given. Each label indicates a
   component of the virtually concatenated signal. The order of the
   labels must reflect the order of the payloads to concatenate (not
   the physical order of time-slots). The above representation limits
   virtual concatenation to remain within a single (component) link;
   it imposes as such a restriction compared to the specification in
   G.707/T1.105.

   In case of multiplication (i.e. using the multiplier transform),
   the explicit ordered list of all labels that take part in the
   Final Signal is given. In case of multiplication of virtually
   concatenated signals, the first set of labels indicates the first
   virtually concatenated signal, the second set of labels indicates
   the second virtually concatenated signal, and so on. The above
   representation limits multiplication to remain within a single
   (component) link.

   The format of the label for SDH and/or SONET TDM-LSR link is:

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               S               |   U   |   K   |   L   |   M   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   For SDH, this is an extension of the numbering scheme defined in
   G.707 section 7.3, i.e. the (K, L, M) numbering. For SONET, the U
   and K fields are not significant and must be set to zero. Only the
   S, L and M fields are significant for SONET and have a similar
   meaning as for SDH.

   Each letter indicates a possible branch number starting at the
   parent node in the multiplex structure. Branches are considered as
   numbered in increasing order, starting from the top of the
   multiplexing structure. The numbering starts at 1, zero is used to
   indicate a non-significant field.



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

   When a field is not significant in a particular context it MUST be
   set to zero when transmitted, and MUST be ignored when received.

   When hierarchical SDH/SONET LSPs are used, an LSP with a given
   bandwidth can be used to tunnel lower order LSPs.  The higher
   order SDH/SONET LSP behaves as a virtual link with a given
   bandwidth (e.g. VC-3), it may also be used as a Forwarding
   Adjacency. A lower order SDH/SONET LSP can be established through
   that higher order LSP. Since a label is local to a (virtual) link,
   the highest part of that label is non-significant and is set to
   zero.

   For instance, a VC-3 LSP can be advertised as a forwarding
   adjacency. In that case all labels allocated between the two ends
   of that LSP will have S, U and K set to zero, i.e., non-
   significant, while L and M will be used to indicate the signal
   allocated in that VC-3.

     1. S is the index of a particular AUG-1/STS-1. S=1->N indicates
     a specific AUG-1/STS-1 inside an STM-N/STS-N multiplex. For
     example, S=1 indicates the first AUG-1/STS-1, and S=N indicates
     the last AUG-1/STS-1 of this multiplex.

     2. U is only significant for SDH and must be ignored for SONET.
     It indicates a specific VC inside a given AUG-1. U=1 indicates a
     single VC-4, while U=2->4 indicates a specific VC-3 inside the
     given AUG-1.

     3. K is only significant for SDH VC-4 and must be ignored for
     SONET and SDH HOVC-3. It indicates a specific branch of a VC-4.
     K=1 indicates that the VC-4 is not further subdivided and
     contains a C-4. K=2->4 indicates a specific TUG-3 inside the VC-
     4. K is not significant when the AUG-1 is divided into AU-3s
     (easy to read and test).

     4. L indicates a specific branch of a TUG-3, VC-3 or STS-1 SPE.
     It is not significant for an unstructured VC-4 or STS-1 SPE. L=1
     indicates that the TUG-3/VC-3/STS-1 SPE is not further
     subdivided and contains a VC-3/C-3 in SDH or the equivalent in
     SONET. L=2->8 indicates a specific TUG-2/VT Group inside the
     corresponding higher order signal.

     5. M indicates a specific branch of a TUG-2/VT Group. It is not
     significant for an unstructured VC-4, TUG-3, VC-3 or STS-1 SPE.
     M=1 indicates that the TUG-2/VT Group is not further subdivided
     and contains a VC-2/VT-6 SPE. M=2->3 indicates a specific VT-3
     inside the corresponding VT Group, these values MUST NOT be used
     for SDH since there is no equivalent of VT-3 with SDH. M=4->6
     indicates a specific VC-12/VT-2 SPE inside the corresponding
     TUG-2/VT Group. M=7->10 indicates a specific VC-11/VT-1.5 SPE
     inside the corresponding TUG-2/VT Group. Note that M=0 denotes
     an unstructured VC-4, VC-3 or STS-1 SPE (easy for debugging).



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

      The M encoding is summarized in the following table:

          M    SDH                          SONET
         ----------------------------------------------------------
          0    unstructured VC-4/VC-3  unstructured STS-1 SPE
          1    VC-2                    VT-6
          2    -                       1st VT-3
          3    -                       2nd VT-3
          4    1st VC-12               1st VT-2
          5    2nd VC-12               2nd VT-2
          6    3rd VC-12               3rd VT-2
          7    1st VC-11               1st VT-1.5
          8    2nd VC-11               2nd VT-1.5
          9    3rd VC-11               3rd VT-1.5
          10   4th VC-11               4th VT-1.5

   In case of contiguous concatenation, the label that is used is the
   lowest label of the contiguously concatenated signal as explained
   before. The higher part of the label indicates where the signal
   starts and the lowest part is not significant. For instance, when
   requesting an STS-48c the label is S>0, U=0, K=0, L=0, M=0.

   Examples of labels:

   Example 1: S>0, U=1, K=1, L=0, M=0
   Denotes the unstructured VC-4 of the Sth AUG-1.

   Example 2: S>0, U=1, K>1, L=1, M=0
   Denotes the unstructured VC-3 of the Kth-1 TUG-3 of the Sth AUG-1.

   Example 3: S>0, U=0, K=0, L=0, M=0
   Denotes the unstructured SPE of the Sth STS-1.

   Example 4: S>0, U=0, K=0, L>1, M=1
   Denotes the VT-6 in the Lth-1 VT Group in the Sth STS-1.

   Example 5: S>0, U=0, K=0, L>1, M=9
   Denotes the 3rd VT-1.5 in the Lth-1 VT Group in the Sth STS-1.


4. Acknowledgments

   Valuable comments and input were received from many people.


5. Security Considerations

   This draft introduce no new security considerations to either
   [GMPLS-RSVP] or [GMPLS-LDP].






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6. References

   [GMPLS-SIG] Ashwood-Smith, P. et al, "Generalized MPLS -
               Signaling Functional Description", Internet Draft,
               draft-ietf-mpls-generalized-signaling-04.txt,
               May 2001.

   [GMPLS-LDP] Ashwood-Smith, P. et al, "Generalized MPLS Signaling -
               CR-LDP Extensions", Internet Draft,
               draft-ietf-mpls-generalized-cr-ldp-03.txt,
               May 2001.

   [GMPLS-RSVP] Ashwood-Smith, P. et al, "Generalized MPLS
                Signaling - RSVP-TE Extensions", Internet Draft,
                draft-ietf-mpls-generalized-rsvp-te-03.txt,
                May 2001.

   [GMPLS-ARCH] E. Mannie Editor, "GMPLS Architecture", Internet
                Draft, draft-many-gmpls-architecture-00.txt, March
                2001.

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

   [RFC2210] Wroclawski, J., "The Use of RSVP with IETF Integrated
             Services," RFC 2210, September 1997.


7. Authors Addresses

      Stefan Ansorge
      Alcatel SEL AG
      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



E. Mannie Editor     Internet-Draft December 2001                   12

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

      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

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

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






E. Mannie Editor     Internet-Draft December 2001                   13

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

      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

      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
      Senior R&D Engineer - Optical Networking
      Alcatel IPO-NSG
      Francis Wellesplein 1,
      B-2018 Antwerpen, Belgium
      Phone: +32 3 240-8491
      Email: Dimitri.Papadimitriou@alcatel.be




E. Mannie Editor     Internet-Draft December 2001                   14

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

      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

      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




E. Mannie Editor     Internet-Draft December 2001                   15

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

      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







































E. Mannie Editor     Internet-Draft December 2001                   16

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

Appendix 1 - Signal Type Values Extension For Group Signals

   This appendix defines the following optional additional Signal
   Type values for the Signal Type field of section 2.1:

       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 that are 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
  or 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 TUG-X, AUG-N and STSG-M as circuit types is not
  described in ANSI and ITU-T standards. The use of these signal types
  in the signaling plane is conceptual.

   These signal types are conceptual objects that intend to designate
   a group of physical objects in the standardized data plane.









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

Appendix 2 - Signal Type Values Extension For VC-3

   This appendix defines the following optional additional Signal
   Type value for the Signal Type field of section 2.1:

       Value         Type
       -----  ---------------------
        20     "VC-3 via AU-3 at the end"

   According to the G.707 standard a VC-3 in the TU-3/TUG-3/VC-4/AU-4
   branch of the SDH multiplex cannot be structured in TUG-2s,
   however a VC-3 in the AU-3 branch can be. In addition, a VC-3
   could be switched between the two branches if required.

   A VC-3 circuit could be terminated on an ingress interface of an
   LSR (e.g. forming a VC-3 forwarding adjacency). This LSR could
   then want to demultiplex this VC-3 and switch internal low order
   LSPs. For implementation reasons, this could be only possible if
   the LSR receives the VC-3 in the AU-3 branch. E.g. for an LSR not
   able to switch internally from a TU-3 branch to an AU-3 branch on
   its incoming interface before demultiplexing and then switching
   the content with its switch fabric.

   In that case it is useful to indicate that the VC-3 LSP must be
   terminated at the end in the AU-3 path instead of the TU-3 path.

   This is achieved by using the "VC-3 via AU-3 at the end" signal
   type. This information can be used, for instance, by the
   penultimate LSR to switch an incoming VC-3 received in any branch
   to the TU-3 branch on the outgoing interface to the destination
   LSR.

   The "VC-3 via AU-3 at the end" signal type does not imply that the
   VC-3 must be switched via the AU-3 branch at some other places.
   The VC-3 signal type indicates that a VC-3 in any branch is
   suitable.



















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

Appendix 3 - Contiguous Concatenation Extension

   This appendix defines the following optional extension flag for
   the Requested Contiguous Concatenation (RCC) field of section 2.1:

      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 for any value of X (X
   less or equal N) in VC-4-Xc/STS-Xc. 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.



































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

Appendix 4 - Virtual Concatenation Extension

   This appendix 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 indicated in section 2.1, identical contiguously
   concatenated signals may be virtual concatenated. In this last
   case, it allows to request the virtual concatenation of, for
   instance, several VC-4-4c/STS-12c SPEs, or any VC-4-Xc/STS-Xc SPEs
   to obtain a VC-4-Xc-Yv/STS-Xc-Yv SPE.

   Note that 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. 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.

   In case of virtual concatenation of a contiguously concatenated
   signal, the same rule as described in section 3 for virtual
   concatenation applies, except that a component of the virtually
   concatenated signal is now itself represented by a list of labels
   because it is concatenated. The first set of labels indicates the
   first contiguously concatenated signal; the second set of labels
   indicates the second contiguously concatenated signal, and so on.

























E. Mannie Editor     Internet-Draft December 2001                   20

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

Appendix 5 - Transparency Extension

   This appendix defines the following optional extension for the
   Transparency field of section 2.1.

  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 untouched, or by tunneling the bytes.

  This specification 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.

  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.

  Line/Multiplex Section layer transparency (refer to section 2.1)
  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.



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

   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
   (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.



















E. Mannie Editor     Internet-Draft December 2001                   22

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

Annex 1 - Examples

   This annex 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 above, signal types are Elementary Signals to which
   successive concatenation, multiplication and transparency
   transforms can be applied.

   1. A VC-4 signal 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
   value 0 to a VC-4 Elementary Signal.

   2. A VC-4-7v signal is formed by the application of RCC with value
   0, NCC with value 0, NVC with value 7 (virtual concatenation of 7
   components), MT with value 1 and T with value 0 to a VC-4
   Elementary Signal.

   3. A VC-4-16c signal is formed by the application of RCC with flag
   1 (standard contiguous concatenation), NCC with value 16, NVC with
   value 0, MT with value 1 and T with value 0 to a VC-4 Elementary
   Signal.

   5. An STM-16 signal with Multiplex Section layer 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 2 to an STM-16
   Elementary Signal.

   6. 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.

   7. An STM-4c signal (i.e. VC-4-4C with the transport overhead)
   with Multiplex Section layer 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 2 applied to an STM-4
   Elementary Signal.

   8. An STM-256c signal with Multiplex Section layer 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 2 applied to an
   STM-256 Elementary Signal.

   9. An STS-1 SPE signal 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 value 0 to an STS-1 SPE Elementary Signal.

   10. An STS-3c SPE signal is formed by the application of RCC with
   value 0 (no contiguous concatenation), NCC with value 0, NVC with
   value 0, MT with value 1 and T with value 0 to an STS-3c SPE
   Elementary Signal.

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


   11. An STS-48c SPE signal is formed by the application of RCC with
   flag 1 (standard contiguous concatenation), NCC with value 16, NVC
   with value 0, MT with value 1 and T with value 0 to an STS-3c SPE
   Elementary Signal.

   12. An STS-1-3v SPE signal is formed by the application of RCC
   with value 0, NVC with value 3 (virtual concatenation of 3
   components), MT with value 1 and T with value 0 to an STS-1 SPE
   Elementary Signal.

   13. An STS-3c-9v SPE signal is formed by the application of RCC
   with value 0, NCC with value 0, NVC with value 9 (virtual
   concatenation of 9 STS-3c), MT with value 1 and T with value 0 to
   an STS-3c SPE Elementary Signal.

   14. An STS-12 signal with Section layer (full) transparency is
   formed by the application of RCC with value 0, NVC with value 0,
   MT with value 1 and T with flag 1 to an STS-12 Elementary Signal.

   15. 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.

   16. 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.

   17. 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.

   18. 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.

   19. 3 x STS-768c SPE signal is formed by the application of RCC
   with flag 1, NCC with value 256, NVC with value 0, MT with value
   3, and T with value 0 to an STS-3c SPE Elementary Signal.

   20. 5 x VC-4-13v composed signal is formed by the application of
   RCC with value 0, NVC with value 13, MT with value 5 and T with
   value 0 to a VC-4 Elementary Signal.

   21. 2 x STS-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.



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

   22. 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.

   23. An STS-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.














































E. Mannie Editor     Internet-Draft December 2001                   25


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