CCAMP Working Group                                   D. Ceccarelli, Ed.
Internet-Draft                                               D. Caviglia
Intended status: Standards Track                                Ericsson
Expires: February 28, June 1, 2013                                           F. Zhang
                                                                   D. Li
                                                     Huawei Technologies
                                                              S. Belotti
                                                               P. Grandi
                                                          Alcatel-Lucent
                                                                  R. Rao
                                                             K. Pithewan
                                                    Infinera Corporation
                                                                J. Drake
                                                                 Juniper
                                                         August 27,
                                                       November 28, 2012

  Traffic Engineering Extensions to OSPF for Generalized MPLS (GMPLS)
                 Control of Evolving G.709 OTN Networks
                 draft-ietf-ccamp-gmpls-ospf-g709v3-03
                 draft-ietf-ccamp-gmpls-ospf-g709v3-04

Abstract

   The recent revision of

   ITU-T Recommendation G.709 [G709-V3] [G.709-2012] has introduced new fixed and
   flexible ODU Optical Data Unit (ODU) containers, enabling optimized
   support for an increasingly abundant service mix.

   This document describes OSPF Open Shortest Path First - Traffic
   Engineering (OSPF-TE) routing protocol extensions to support
   Generalized MPLS (GMPLS) control of all currently defined ODU
   containers, in support of both sub-lambda and lambda level routing
   granularity.

Status of this Memo

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   This Internet-Draft will expire on February 28, June 1, 2013.

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   Copyright (c) 2012 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3  4
     1.1.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  3  4
   2.  OSPF-TE Extensions . . . . . . . . . . . . . . . . . . . . . .  3  4
   3.  TE-Link Representation . . . . . . . . . . . . . . . . . . . .  4  6
   4.  ISCD format extensions . . . . . . . . . . . . . . . . . . . .  5  7
     4.1.  Switch Capability Specific Information . . . . . . . . . .  7  8
       4.1.1.  Switch Capability Specific Information for fixed
               containers . . . . . . . . . . . . . . . . . . . . . .  9
       4.1.2.  Switch Capability Specific Information for
               variable containers  . . . . . . . . . . . . . . . . . 10
       4.1.3.  Switch Capability Specific Information - Field
               values and explanation . . . . . . . . . . . . . . . . 12
   5.  Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 14
     5.1.  MAX LSP Bandwidth fields in the ISCD . . . . . . . . . . . 13 14
     5.2.  Example of T,S and TSG utilization . . . . . . . . . . . . 15 16
       5.2.1.  Example of different TSGs  . . . . . . . . . . . . . . 16 17
     5.3.  Example of ODUflex advertisement . . . . . . . . . . . . . 18 19
     5.4.  Example of single stage muxing . . . . . . . . . . . . . . 20 21
     5.5.  Example of multi stage muxing - Unbundled link . . . . . . 22 23
     5.6.  Example of multi stage muxing - Bundled links  . . . . . . 23 24
     5.7.  Example of component links with non homogeneous
           hierarchies  . . . . . . . . . . . . . . . . . . . . . . . 25 26
   6.  Compatibility  . . . . . . . . . . . . . . . . . . . . . . . . 27 28
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 27 28
   8.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 27 28
   9.  Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 28 29
   10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 29 30
   11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 29 30
     11.1. Normative References . . . . . . . . . . . . . . . . . . . 29 30
     11.2. Informative References . . . . . . . . . . . . . . . . . . 30 31
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 31 32

1.  Introduction

   G.709 OTN [G709-V3] Optican Transport Network (OTN) [G.709-2012] includes new fixed
   and flexible ODU containers, two types of Tributary Slots (i.e.,
   1.25Gbps and 2.5Gbps), and supports various multiplexing
   relationships (e.g., ODUj multiplexed into ODUk (j<k)), two different
   tributary slots for ODUk (K=1, 2, 3) and ODUflex service type, which
   is being standardized in ITU-T.  In order to present this information
   in the routing process, this document provides OTN technology
   specific encoding for OSPF-TE.

   For a short overview of OTN evolution and implications of OTN
   requirements on GMPLS routing please refer to [OTN-FWK].  The
   information model and an evaluation against the current solution are
   provided in [OTN-INFO].

   The routing information for Optical Channel Layer (OCh) (i.e.,
   wavelength) is out of the scope of this document.  Please refer to
   [WSON-Frame]
   [RFC6163] and [RFC6566] for further information.

1.1.  Terminology

   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.  OSPF-TE Extensions

   In terms of GMPLS based OTN networks, each OTUk can be viewed as a
   component link, and each component link can carry one or more types
   of ODUj (j<k).

   Each TE LSA Link State Advertisement (LSA) can carry a top-level link TLV
   Type Lenght Value (TLV) with several nested sub-
   TLVs sub-TLVs to describe
   different attributes of a TE link.  Two top-level TLVs are defined in [RFC 3630].
   [RFC3630]. (1) The Router Address TLV (referred to as the Node TLV)
   and (2) the TE link TLV.  One or more sub-TLVs can be nested into the
   two top-level TLVs.  The sub-TLV set for the two top-level TLVs are
   also defined in [RFC 3630] [RFC3630] and [RFC 4203]. [RFC4203].

   As discussed in [OTN-FWK] and [OTN-INFO], the OSPF-TE must be extended so
   to be able to advertise the termination and switching capabilites
   related to each different ODUj and ODUk/OTUk (Optical Transport Unit)
   and the advertisement of related multiplexing capabilities.  This
   leads to the need to define a new Switching Capability value and
   associated new Switching Capability for the ISCD. Interface Switching
   Capability Descriptor (ISCD).

   In the following we will use ODUj to indicate a service type that is
   multiplexed into an higher order ODU, ODUk an to indicate a higher order
   ODU including an ODUj and ODUk/OTUk to indicate the layer mapped into
   the OTUk.  Moreover ODUj(S) and ODUk(S) are used to indicate ODUj and
   ODUk supporting switching capability only, and the ODUj->ODUk format
   is used to indicate the ODUj into ODUk multiplexing capability.

   This notation can be iterated repeated as needed depending on the number of
   multiplexing levels.  In the following the term "multiplexing tree"
   is used to identify a multiplexing hierarchy where the root is always
   a server ODUk/OTUk and any other supported multiplexed container is
   represented with increasing granularity until reaching the leaf of
   the tree.  The tree can be structured with more than one branch if
   the server ODUk/OTUk supports more than one hierarchy.

   If for example a multiplexing hierarchy like the following one is
   considered:

             ODU2 ODU0    ODUflex ODU0
                \ /            \ /
                 |              |
               ODU3           ODU2
                  \            /
                   \          /
                    \        /
                     \      /
                       ODU4

   The ODU4 is the root of the muxing tree, ODU3 and ODU2 are containers
   directly multiplexed into the server and then ODU2, ODU0 are the
   leaves of the ODU3 branch, while ODUflex and ODU0 are the leaves of
   the ODU2 one.  This means that on this traffic card it is possible to
   have the following multiplexing capabilities:

           ODU2->ODU3->ODU4
           ODU0->ODU3->ODU4
           ODUflex->ODU2->ODU4
           ODU0->ODU2->ODU4

3.  TE-Link Representation

   G.709 ODUk/OTUk Links are represented as TE-Links in GMPLS Traffic
   Engineering Topology for supporting ODUj layer switching.  These TE-
   Links can be modeled in multiple ways.  Some of the prominent
   representations are captured below.

   OTUk physical Link(s) can be modeled as a TE-Link(s).  The TE-Link is
   termed
   refferd to as OTUk-TE-Link.  The OTUk-TE-Link advertises ODUj
   switching capacity.  The advertised capacity could include ODUk
   switching capacity.  Figure-1 below provides an illustration of one
   hop ODUk TE-links.

           +-------+               +-------+               +-------+
           |  OTN  |               |  OTN  |               |  OTN  |
           |Switch |<- OTUk Link ->|Switch |<- OTUk Link ->|Switch |
           |   A   |               |   B   |               |   C   |
           +-------+               +-------+               +-------+

                   |<-- TE-Link -->|       |<-- TE-Link -->|

                          Figure 1: ODUk TE-Links

   It is possible to create TE-Links that span more than one hop by
   creating FA between non-adjacent nodes.  Such TE-Links are also
   termed ODUk-TE-Links.  As in the one hop case, these types of ODUk-
   TE-Links also advertise ODUj switching capacity.  The advertised
   capacity could include ODUk switching capacity.

           +-------+               +-------+               +-------+
           |  OTN  |               |  OTN  |               |  OTN  |
           |Switch |<- OTUk Link ->|Switch |<- OTUk Link ->|Switch |
           |   A   |               |   B   |               |   C   |
           +-------+               +-------+               +-------+
                                 ODUk Switched

                   |<------------- ODUk Link ------------->|
                   |<-------------- TE-Link--------------->|

                      Figure 2: Multiple hop TE-Link

4.  ISCD format extensions

   The Interface Switching Capability Descriptor ISCD describes the switching capability of an interface [RFC 4202].
   [RFC4202].  This document defines a new Switching Capability value
   for OTN [G.709-v3] [G.709-2012] as follows:

   Value                       Type
   -----                       ----
   101
   110 (TBA by IANA)           OTN-TDM capable (OTN-TDM)

   When supporting the extensions defined in this document, the
   Switching Capability and Encoding values MUST be used as follows:

   - Switching Capability = OTN-TDM
   - Encoding Type = G.709 ODUk (Digital Path) [as defined in RFC4328]

   Both for fixed and flexible ODUs use the same switching type and encoding
   values.
   values MUST be used.  When Switching Capability and Encoding fields
   are set to values as stated above, the Interface Switching Capability
   Descriptor MUST be interpreted 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
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         | Switching Cap |   Encoding    |           Reserved            |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                  Max defined in [RFC4203].

   Maximum LSP Bandwidth at priority 0              |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                  Max

   The MAX LSP Bandwidth at priority 1              |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                  Max LSP Bandwidth at priority 2              |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                  Max LSP Bandwidth at priority 3              |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                  Max LSP Bandwidth at priority 4              |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                  Max LSP Bandwidth at priority 5              |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                  Max LSP Bandwidth at priority 6              |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                  Max LSP Bandwidth at priority 7              |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                Switch Capability Specific Information         |
         |                        (variable length)                      |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Maximum LSP Bandwidth

   The MAX LSP bandwidth field is used according to [RFC4203]: i.e. 0 <= bandwidth field MUST be used according to [RFC4203]: i.e.
   0 <= Max LSP Bandwidth <= ODUk/OTUk and intermediate values are those
   on the branch of OTN switching hierarchy supported by the interface.
   E.g. in the OTU4 link it could be possible to have ODU4 as MAX LSP
   Bandwidth for some priorities, ODU3 for others, ODU2 for some others
   etc.  The bandwidth unit MUST be in bytes per second and the encoding
   MUST be in IEEE Institute of Electrical and Electronic Engineers (IEEE)
   floating point format.  The discrete values for various ODUs is shown
   in the table below.

+----------------------+---------------------------------+------------------+

+---------------------+------------------------------+-----------------+
|     ODU Type        |    ODU nominal bit rate      |Value in Byte/Sec |
+----------------------+---------------------------------+------------------+ Byte/Sec|
+---------------------+------------------------------+-----------------+
|       ODU0          |      1 244 160 kbits/s       |    0x4D1450C0   |
|       ODU1          | 239/238 x 2 488 320 kbit/s   |    0x4D94F048   |
|       ODU2          | 239/237 x 9 953 280 kbit/s   |    0x4E959129   |
|       ODU3          | 239/236 x 39 813 120 kbit/s  |    0X4F963367   |
|       ODU4          | 239/227 x 99 532 800 kbit/s  |    0x504331E3   |
|       ODU2e         | 239/237 x 10 312 500 kbit/s  |    0x4E9AF70A   |
|                     |                              |                 |
|  ODUflex for CBR    |                              |     MAX LSP     |
|  Client signals     |239/238     |    239/238 x client signal bit rate   |    BANDWIDTH    |
|                     |           bit rate           |                 |
| ODUflex for GFP-F   |                              |     MAX LSP     |
|Mapped client signal |      Configured bit rate     |    BANDWIDTH    |
|                     |                              |                 |
|                     |                              |                 |
| ODU
|ODU flex resizable   |      Configured bit rate     |     MAX LSP     |
|                     |                              |    BANDWIDTH    |
+----------------------+---------------------------------+------------------+
+---------------------+------------------------------+-----------------+

   A single ISCD MAY be used for the advertisement of unbundled or
   bundled links supporting homogeneous multiplexing hierarchies and the
   same Tributary Slot Granularity (TSG).  A different ISCD MUST be used
   for each different muxing hierarchy (muxing tree in the following
   examples) and different TSG supported within the TE Link, if it
   includes component Link.

   Component links with differing characteristics. different hierarchies or TSG MUST NOT be
   bundled.

4.1.  Switch Capability Specific Information

   The technology specific part of the OTN ISCD may include a variable
   number of sub-TLVs called Bandwidth sub-TLVs.  Each sub-TLV is
   encoded with the TLV header as defined in [RFC3630] section 2.3.2.
   The muxing hierarchy tree MUST be encoded as an order independent list of them.
   list.  Two types of Bandwidth TLV are defined (TBA by IANA):

      - Type 1 - Unreserved Bandwidth for fixed containers

      - Type 2 - Unreserved/MAX LSP Bandwidth for flexible containers

   The format of the SCSI MUST be as depicted in the following figure: figure,
   where one Type 1 sub-TLV MUST be used for any fixed container and one
   Type 2 sub-TLV MUST be used for any variable container.  Different
   sub-TLV MAY be presented in ascending Type order.

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                         Fixed Container                       |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ~                               ...                             ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type = 2 (Unres/MAX-var)  |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                      Variable Container                       |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                           Figure 3: SCSI format

4.1.1.  Switch Capability Specific Information for fixed containers

   The format of the two different types of Bandwidth TLV are for fixed containers is depicted in
   the following figures: figure:

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Signal type  | Num of stages |T|S| TSG | Res |   Priority    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Stage#1    |      ...      |   Stage#N     |    Padding    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Unres ODUj at Prio 0      |     Unres ODUj at Prio 1      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Unres ODUj at Prio 2      |     Unres ODUj at Prio 3      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Unres ODUj at Prio 4      |     Unres ODUj at Prio 5      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Unres ODUj at Prio 6      |     Unres ODUj at Prio 7      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 4: Bandwidth TLV - Type 1 -

   The values of the fields shown in figure 4 are explained after figure
   6. in section
   4.1.3.

4.1.2.  Switch Capability Specific Information for variable containers

   The format of the Bandwidth TLV for variable containers is depicted
   in the following figure:

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Type = 2 (Unres/MAX-var)   |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Signal type  | Num of stages |T|S| TSG | Res |   Priority    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Stage#1    |      ...      |   Stage#N     |    Padding    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Unreserved Bandwidth at priority 0             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Unreserved Bandwidth at priority 1             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Unreserved Bandwidth at priority 2             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Unreserved Bandwidth at priority 3             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Unreserved Bandwidth at priority 4             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Unreserved Bandwidth at priority 5             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Unreserved Bandwidth at priority 6             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Unreserved Bandwidth at priority 7             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP Bandwidth at priority 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP Bandwidth at priority 1               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP Bandwidth at priority 2               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP Bandwidth at priority 3               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP Bandwidth at priority 4               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP Bandwidth at priority 5               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP Bandwidth at priority 6               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP Bandwidth at priority 7               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 5: Bandwidth TLV - Type 2 -

   The values of the fields shown in figure 4 are explained in section
   4.1.3.

4.1.3.  Switch Capability Specific Information - Field values and
        explanation

   The fields in the Bandwidth TLV MUST be filled as follows:

      - Signal Type: Indicates the ODU type being advertised
            Value        Type
            -----        ------
            1            ODU1
            2            ODU2
            3            ODU3
            4            ODU4
            10           ODU0
            11           ODU2e
            20           ODUflex CBR
            21           ODUflex GFP-F resizable
            22           ODUflex GFP-F non resizable
            230-256      Experimental advertised.  Values
      are defined in [OTN-SIG].

         With respect to ODUflex, ODUflex CBR Constant Bit Rate (CBR) and
         ODUflex GFP-F Generig Framing Procedure-Frame mapped (GFP-F) MUST
         always be advertised separately as they use different
         adaptation functions.  In the case both GFP-F resizable and non
         resizable (i.e. 21 and 22) are supported, Signal Type 21
         implicitely supports also signal Signal Type 22, so only Signal
         Type 21 MUST be advertised.  Signal Type 22 MUST be used only
         for non resizable resources.

      - Number of stages: Indicates the number of multiplexing stages
      level.  It
      level below the indicated signal type.  It MUST be equal to 0 when
      a server layer is being advertised, 1 in case of single stage
      muxing, 2 in case of dual stage muxing, etc.

      - Flags:

         - T Flag (bit 17): Indicates whether the advertised bandwidth
         can be terminated.  When T=1, the signal type can be
         terminated, terminated T
         MUST be set, while when T=0, the signal type cannot be terminated. terminated T
         MUST be cleared.

         - S Flag (bit 18): Indicates whether the advertised bandwidth
         can be switched.  When S=1, the signal type can be switched, switched S MUST
         be set, while when S=0, the signal type cannot be switched. switched S MUST be
         cleared.

         The value 00 0 in both T and S bits MUST NOT be used.

      - TSG: Tributary Slot Granularity (3bit): (3 bits): Used for the
      advertisement of the supported Tributary Slot granularity granularity.  The
      following values MUST be used:

         - 0 - Reserved Ignored

         - 1 - 1.25 Gbps/2.5Gbps

         - 2 - 2.5 Gbps only

         - 3 - 1.25 Gbps only
         - 4 - Don't care

         - 5-7 4-7 - Reserved

      Where value 1 is used on those interfaces where the fallback
      procedure is enabled and the default value of 1.25 Gbps can be
      falled back to 2.5 if needed.  Values 2 and 3 are used where there
      is no chance to modify the TSG.  In the former case the interface
      being advertised is a G.709v1 [RFC4328] G.709 and in the latter the
      interface is a
      G.709v3 [G.709-2012] with fallback procedure disabled or
      unavailable.  Value 4 0 is used for non multiplexed signal (i.e. non
      OTN client).

      - Priority :8 bits (8 bits): field with 1 flag for each priority.  Bit  Each
      bit MUST be set
      indicates when the related priority supported, bit is supported and MUST be
      cleared means when the related priority is not supported.  The priority
      0 is related to the most significant bit.  When no priority is
      supported, priority 0 MUST be advertised.

      - Stage#1 ...  Stage#N : These fields are 8 bits long.  Their
      number is variable and a field is present for each stage of the
      muxing hierarchy.
      indicated number of stages.  The last one MUST always indicate the
      server ODU container (ODUk/OTUk). (ODUk/OTUk) and they MUST be listed in
      ascending order.  The values of the Stage fields MUST be the same
      ones defined for the Signal Type field.  If the number of stages
      is 0, then no the Stage and Padding fields MUST be included. omitted.

      - Padding: Given that the number of Stages is variable, padding to
      32 bits field MUST be used when needed.

      - Unreserved Bandwidth/Max LSP BW : In case of fixed containers
      (Type=1) the Unreserved Bandwidth field MUST be 16 bits long and
      indicates the Unreserved Bandwidth in number of available
      containers.  Only  Unreserved/MAX LSP BW fields for supported
      priorities each identified
      priority MUST be included, in order of increasing prioritiy (0 to 7).
      7) and Unreserved/MAX LSP BW fields for other priority values MUST
      be omitted.  In case the number of supported priorities is odd, a
      16 bits all zeros padding field MUST be added.  On the other hand,
      in case of variable containers (Type 2) the Unreserved/MAX LSP
      Bandwidth fields MUST be 32 bits long and expressed in IEEE
      floating point format.  The advertisement of the MAX LSP bandwidth
      MUST take into account HO OPUk bit rate tolerance and be
      calculated according to the following formula:

         Max LSP BW = (# available TS) * (ODTUk.ts nominal bit rate) *
         (1-HO OPUk bit rate tolerance)

      Only

      Unreserved/MAX LSP bandwidth for each supported priorities prioritiy MUST be
      advertised.

5.  Examples

   The examples in the following pages are not normative and are not
   intended to infer imply or mandate any specific implementation.

5.1.  MAX LSP Bandwidth fields in the ISCD

   This example shows how the MAX LSP Bandwidth fields of the ISCD are
   filled accordingly to the evolving of the TE-link bandwidth
   occupancy.  In the example an OTU4 link is considered, with supported
   priorities 0,2,4,7 and muxing hierarchy ODU1->ODU2->ODU3->ODU4.

   At time T0, with the link completely free, the advertisement would
   be:

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Switching Cap |   Encoding    |           Reserved            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 0 = 100Gbps         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 1 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 2 = 100Gbps         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 3 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 4 = 100Gbps         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 5 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 6 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 7 = 100Gbps         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Switch Capability Specific Information         |
   |                        (variable length)                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Figure 6: Example 1 - MAX LSP Bandwidth fields in the ISCD @T0

   At time T1 an ODU3 at priority 2 is set-up, so for priority 0 the MAX
   LSP Bandwidth is still equal to the ODU4 bandwidth, while for
   priorities from 2 to 7 (excluding the non supported ones) the MAX LSP
   Bandwidth is equal to ODU3, as no more ODU4s are available and the
   next supported ODUj in the hierarchy is ODU3.The advertisement is
   updated 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Switching Cap |   Encoding    |           Reserved            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 0 = 100Gbps         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 1 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 2 = 40Gbps          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 3 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 4 = 40Gbps          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 5 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 6 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 7 = 40Gbps          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Switch Capability Specific Information         |
   |                        (variable length)                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Figure 7: Example 1 - MAX LSP Bandwidth fields in the ISCD @T1

   At time T2 an ODU2 at priority 4 is set-up.  The first ODU3 is no
   longer available since T1 as it was kept by the ODU3 LSP, while the
   second is no more available and just 3 ODU2 are left in it.  ODU2 is
   now the MAX LSP bandwidth for priorities higher than 4.  The
   advertisement is updated 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Switching Cap |   Encoding    |           Reserved            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 0 = 100Gbps         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 1 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 2 = 40Gbps          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 3 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 4 = 10Gbps          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 5 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 6 = 0               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Max LSP Bandwidth at priority 7 = 10Gbps          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Switch Capability Specific Information         |
   |                        (variable length)                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Figure 8: Example 1 - MAX LSP Bandwidth fields in the ISCD @T2

5.2.  Example of T,S and TSG utilization

   In this example an interface with Tributary Slot Type 1.25 Gbps and
   fallback procedure enabled is considered (TSG=1).  It supports the
   simple ODU1->ODU2->ODU3 hierarchy and priorities 0 and 3.  Suppose
   that in this interface the ODU3 signal type can be both switched or
   terminated, the ODU2 can only be terminated and the ODU1 switched
   only.  For the advertisement of the capabilities of such interface a
   single ISCD is used and its format is 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU1  |  #stages= 2   |T0|S1|001| Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU2  | Stage#2=ODU3  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Unres ODU1 at Prio 0      |     Unres ODU1 at Prio 3      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU2  |  #stages= 1   |T1|S0|001| Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU3  |                  Padding                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Unres ODU2 at Prio 0      |     Unres ODU2 at Prio 3      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 8          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU3  |  #stages= 0   |T1|S1|001| Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Unres ODU3 at Prio 0      |     Unres ODU3 at Prio 3      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

              Figure 9: Example 2 - TSG, T and S utilization

5.2.1.  Example of different TSGs

   In this example two interfaces with homogeneous hierarchies but
   different Tributary Slot Types are considered.  The first one
   supports a G.709v1 [RFC4328] interface (TSG=2) while the second one a G.709v3 G.709-
   2012 interface with fallback procedure disabled (TSG=3).  Both of
   them support ODU1->ODU2->ODU3 hierarchy and priorities 0 and 3.  For
   the advertisement of the capabilities of such interfaces two
   different ISCDs are used and the format of their SCSIs is as follows:

   SCSI of ISCD 1 - TSG=2
   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU1  |  #stages= 2   |T|S| 2 |  Res  |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU2  | Stage#2=ODU3  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Unres ODU1 at Prio 0      |     Unres ODU1 at Prio 3      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   SCSI of ISCD 2 - TSG=3
   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU1  |  #stages= 2   |T|S| 3 |  Res  |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU2  | Stage#2=ODU3  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Unres ODU1 at Prio 0      |     Unres ODU1 at Prio 3      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

            Figure 10: Example 2.1 - Different TSGs utilization

   A particular case in which hierarchies with the same muxing tree but
   with different exported TSG must MUST be considered as non homogenous
   hierarchies is the case in which an H-LPS and the client LSP are
   terminated on the same egress node.  What can happen is that a loose
   ero
   Explicit Route Object (ERO) is used at the hop where the signaled LSP
   is nested into the
   H-LSP Hierarchical-LSP (H-LSP) (penultimate hop of the
   LSP).

   In the following figure, node C receives from A a loose ERO towards
   node E and must choose between the ODU2 H-LSP on if1 or the one on
   if2.  In case the H-LSP on if1 exports a TS=1,25Gbps TS=1.25Gbps and if2 a
   TS=2,5Gbps
   TS=2.5Gbps and the service LSP being signaled needs a 1,25Gbps 1.25Gbps
   tributary slot, only the H-LSP on if1 can be used to reach node E.
   For further details please see section 4.1 of the [OTN-INFO].

                          ODU0-LSP
         ..........................................................+
         |                                                         |
         |                                     ODU2-H-LSP          |
         |                         +-------------------------------+
         |                         |                               |
      +--+--+      +-----+      +-----+ if1     +-----+         +-----+
      |     | OTU3 |     | OTU3 |     |---------|     |---------|     |
      |  A  +------+  B  +------+  C  | if2     |  D  |         |  E  |
      |     |      |     |      |     |---------|     |---------|     |
      +-----+      +-----+      +-----+         +-----+         +-----+

            ... Service LSP
            --- H-LSP

    Figure 11: Example - Service LSP and H-LSP terminating on the same
                                   node

5.3.  Example of ODUflex advertisement

   In this example the advertisement of an ODUflex->ODU3 hierarchy is
   shown.  In case of ODUflex advertisement the MAX LSP bandwidth needs
   to be advertised and in some cases also information about the
   Unreserved bandwidth could be useful.  The amount of Unreserved
   bandwidth does not give a clear indication of how many ODUflex LSP
   can be set up either at the MAX LSP Bandwidth or at different rates,
   as it gives no information about the spatial allocation of the free
   TSs.

   An indication of the amount of Unreserved bandwidth could be useful
   during the path computation process, as shown in the following
   example.  Supposing there are two TE-links (A and B) with MAX LSP
   Bandwidth equal to 10 Gbps each.  In case 50Gbps of Unreserved
   Bandwidth are available on Link A, 10Gbps on Link B and 3 ODUflex
   LSPs of 10 GBps each, have to be restored, for sure only one can be
   restored along Link B and it is probable (but not sure) that two of
   them can be restored along Link A.

   In the case of ODUflex advertisement the Type 2 Bandwidth TLV is
   used.

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Type = 2 (Unres/MAX-var)   |           Length  = 72        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |S. type=ODUflex|  #stages= 1   |T|S| TSG | Res |   Priority    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Stage#1=ODU3 |                   Padding                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Unreserved Bandwidth at priority 0              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Unreserved Bandwidth at priority 1              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Unreserved Bandwidth at priority 2              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Unreserved Bandwidth at priority 3              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Unreserved Bandwidth at priority 4              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Unreserved Bandwidth at priority 5              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Unreserved Bandwidth at priority 6              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Unreserved Bandwidth at priority 7              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP  Bandwidth at priority 0              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP  Bandwidth at priority 1              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP  Bandwidth at priority 2              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP  Bandwidth at priority 3              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP  Bandwidth at priority 4              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP  Bandwidth at priority 5              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP  Bandwidth at priority 6              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MAX LSP  Bandwidth at priority 7              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

               Figure 12: Example 3 - ODUflex advertisement

5.4.  Example of single stage muxing

   Supposing there is 1 OTU4 component link supporting single stage
   muxing of ODU1, ODU2, ODU3 and ODUflex, the supported hierarchy can
   be summarized in a tree as in the following figure.  For sake of
   simplicity we assume that also in this case only priorities 0 and 3
   are supported.

          ODU1 ODU2  ODU3 ODUflex
             \   \    /   /
              \   \  /   /
               \   \/   /
                  ODU4

   and the related SCSIs 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 8          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU4  |  #stages= 0   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU4 at Prio 0 =1     |    Unres ODU4 at Prio 3 =1    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU1  |  #stages= 1   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU4  |                  Padding                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU1 at Prio 0 =40    |    Unres ODU1 at Prio 3 =40   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU2  |  #stages= 1   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU4  |                  Padding                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU2 at Prio 0 =10    |    Unres ODU2 at Prio 3 =10   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU3  |  #stages= 1   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU4  |                  Padding                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU3 at Prio 0 =2     |    Unres ODU3 at Prio 3 =2    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Type = 2 (Unres/MAX-var)   |           Length = 24         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |S. type=ODUflex|  #stages= 1   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Stage#1=ODU4 |                   Padding                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Unreserved Bandwidth at priority 0 =100Gbps        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Unreserved Bandwidth at priority 3 =100Gbps        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |              MAX LSP Bandwidth at priority 0 =100Gbps         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |              MAX LSP Bandwidth at priority 3 =100Gbps         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                Figure 13: Example 4 - Single stage muxing

5.5.  Example of multi stage muxing - Unbundled link

   Supposing there is 1 OTU4 component link with muxing capabilities as
   shown in the following figure:

          ODU2 ODU0    ODUflex ODU0
             \ /            \ /
              |              |
            ODU3           ODU2
               \            /
                \          /
                 \        /
                  \      /
                    ODU4

   and supported pririties 0 and 3, the advertisement is composed by the
   following Bandwidth TLVs:

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 8          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU4  |  #stages= 0   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU4 at Prio 0 =1     |    Unres ODU4 at Prio 3 =1    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU3  |  #stages= 1   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Stage#1=ODU4 |                   Padding                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU3 at Prio 0 =2     |    Unres ODU3 at Prio 3 =2    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU2  |  #stages= 1   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Stage#1=ODU4 |                   Padding                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU2 at Prio 0 =10    |    Unres ODU2 at Prio 3 =10   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU2  |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU3  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU2 at Prio 0 =8     |    Unres ODU2 at Prio 3 =8    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU0  |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU3  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU0 at Prio 0 =64    |    Unres ODU0 at Prio 3 =64   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU0  |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU2  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU0 at Prio 0 =80    |    Unres ODU0 at Prio 3 =80   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Type = 2 (Unres/MAX-var)   |           Length = 24         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |S.type=ODUflex |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU2  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Unreserved Bandwidth at priority 0 =100Gbps        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Unreserved Bandwidth at priority 3 =100Gbps        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            MAX LSP Bandwidth at priority 0 =10Gbps            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            MAX LSP Bandwidth at priority 3 =10Gbps            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Figure 14: Example 5 - Multi stage muxing - Unbundled link

5.6.  Example of multi stage muxing - Bundled links

   In this example 2 OTU4 component links with the same supported TSG
   and homogeneous muxing hierarchies are considered.  The following
   muxing capabilities trees are supported:

   Component Link#1      Component Link#2
      ODU2 ODU0             ODU2 ODU0
         \ /                   \ /
          |                     |
         ODU3                  ODU3
          |                     |
         ODU4                  ODU4

   Considering only supported priorities 0 and 3, the advertisement is
   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 8          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU4  |  #stages= 0   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU4 at Prio 0 =2     |    Unres ODU4 at Prio 3 =2    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU3  |  #stages= 1   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Stage#1=ODU4 |                   Padding                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU3 at Prio 0 =4     |    Unres ODU3 at Prio 3 =4    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU2  |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU3  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU2 at Prio 0 =16    |    Unres ODU2 at Prio 3 =16   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU0  |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU3  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU0 at Prio 0 =128   |    Unres ODU0 at Prio 3 =128  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         Figure 15: Example 6 - Multi stage muxing - Bundled links

5.7.  Example of component links with non homogeneous hierarchies

   In this example 2 OTU4 component links with the same supported TSG
   and non homogeneous muxing hierarchies are considered.  The following
   muxing capabilities trees are supported:

   Component Link#1      Component Link#2
      ODU2 ODU0             ODU1 ODU0
         \ /                   \ /
          |                     |
         ODU3                  ODU2
          |                     |
         ODU4                  ODU4

   Considering only supported priorities 0 and 3, the advertisement uses
   two different ISCDs, one for each hierarchy.  In the following
   figure, the SCSI of each ISCD is shown:

   SCSI of ISCD 1 - Component Link#1

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 8          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU4  |  #stages= 0   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU4 at Prio 0 =1     |    Unres ODU4 at Prio 3 =1    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU3  |  #stages= 1   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Stage#1=ODU4 |                   Padding                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU3 at Prio 0 =2     |    Unres ODU3 at Prio 3 =2    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU2  |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU3  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU2 at Prio 0 =8     |    Unres ODU2 at Prio 3 =8    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU0  |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU3  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU0 at Prio 0 =64    |    Unres ODU0 at Prio 3 =64   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   SCSI of ISCD 2 - Component Link#2

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 8          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU4  |  #stages= 0   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU4 at Prio 0 =1     |    Unres ODU4 at Prio 3 =1    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU2  |  #stages= 1   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Stage#1=ODU4 |                   Padding                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU2 at Prio 0 =10    |    Unres ODU2 at Prio 3 =10   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU1  |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU2  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU1 at Prio 0 =40    |    Unres ODU1 at Prio 3 =40   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Type = 1 (Unres-fix)   |           Length = 12         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Sig type=ODU0  |  #stages= 2   |T|S| TSG | Res |1|0|0|1|0|0|0|0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Stage#1=ODU2  | Stage#2=ODU4  |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Unres ODU0 at Prio 0 =80    |    Unres ODU0 at Prio 3 =80   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        Figure 16: Example 7 - Multi stage muxing - Non homogeneous
                                hierarchies

6.  Compatibility

   All implementations of this document MAY support also advertisement
   as defined in [RFC4328].  When nodes support both advertisement
   methods, implementations MUST support the configuration of which
   advertisement method is followed.  The choice of which is used is
   based on policy and is out of scope of the document.  This enables
   nodes following each method to identify similar supporting nodes and
   compute paths using only the appropriate nodes.

7.  Security Considerations

   This document document, as [RFC4203], specifies the contents of Opaque LSAs in
   OSPFv2.  As Opaque LSAs are not used for SPF computation or normal
   routing, the extensions specified here have no direct effect on IP
   routing.  Tampering with GMPLS TE LSAs may have an effect on the
   underlying transport (optical and/or SONET-SDH) network.  [RFC3630]
   suggests mechanisms such as [RFC2154] to protect the transmission of
   this information, and those or other mechanisms should be used to
   secure and/or authenticate the information carried in the Opaque
   LSAs.

   For security threats, defensive techniques, monitoring/detection/
   reporting of security attacks and requirements please refer to
   [RFC5920] .

8.  IANA Considerations

   Upon approval of this document, IANA will make the assignment of a
   new Switching Capability value for registry, the existing ISCD located at http:
   //www.iana.org/assignments/ospf-traffic-eng-tlvs/
   ospf-traffic-eng-tlvs.xml:

           15     Interface Switching Capability Descriptor      [RFC4203] "OTN-TDM Container Registry" under a new GMPLS
   Routing Parameters" with two new types (1 and 2)

   Switching capability Type           Description                Reference
   ----------------------  --------------------------  ----------
           101
   110 (suggested)          OTN-TDM capable (OTN-TDM)  [This.I-D]

   This document defines the following sub-TLVs of the ISCD TLV:

   Value  Sub-TLV
   -----  -------------------------------------------------
     1      Unreserved Bandwidth for fixed containers
     2      Unreserved/MAX LSP bandwidth for flexible containers

9.  Contributors

      Xiaobing Zi, Huawei Technologies

      Email: zixiaobing@huawei.com

      Francesco Fondelli, Ericsson

      Email: francesco.fondelli@ericsson.com

      Marco Corsi

      EMail: corsi.marco@gmail.com

      Eve Varma, Alcatel-Lucent

      EMail: eve.varma@alcatel-lucent.com

      Jonathan Sadler, Tellabs

      EMail: jonathan.sadler@tellabs.com

      Lyndon Ong, Ciena

      EMail: lyong@ciena.com

      Ashok Kunjidhapatham

      akunjidhapatham@infinera.com
      Snigdho Bardalai

      sbardalai@infinera.com

      Steve Balls

      Steve.Balls@metaswitch.com

      Jonathan Hardwick

      Jonathan.Hardwick@metaswitch.com

      Xihua Fu

      fu.xihua@zte.com.cn

      Cyril Margaria

      cyril.margaria@nsn.com

      Malcolm Betts

      Malcolm.betts@zte.com.cn

10.  Acknowledgements

   The authors would like to thank Fred Gruman and Lou Berger for the
   precious comments and suggestions.

11.  References

11.1.  Normative References

   [OTN-FWK]  F.Zhang, D.Li, H.Li, S.Belotti, D.Ceccarelli, "Framework
              for GMPLS and PCE Control of G.709 Optical Transport
              networks, work in progress
              draft-ietf-ccamp-gmpls-g709-framework-05", September 2011.

   [OTN-INFO]
              S.Belotti, P.Grandi, D.Ceccarelli, D.Caviglia, F.Zhang,
              D.Li, "Information model for G.709 Optical Transport
              Networks (OTN), work in progress
              draft-ietf-ccamp-otn-g709-info-model-02", October 2011.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2154]  Murphy, S., Badger, M., and B. Wellington, "OSPF with
              Digital Signatures", RFC 2154, June 1997.

   [RFC2328]  Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.

   [RFC2370]  Coltun, R., "The OSPF Opaque LSA Option", RFC 2370,
              July 1998.

   [RFC3630]  Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
              (TE) Extensions to OSPF Version 2", RFC 3630,
              September 2003.

   [RFC4201]  Kompella, K., Rekhter, Y., and L. Berger, "Link Bundling
              in MPLS Traffic Engineering (TE)", RFC 4201, October 2005.

   [RFC4202]  Kompella, K. and Y. Rekhter, "Routing Extensions in
              Support of Generalized Multi-Protocol Label Switching
              (GMPLS)", RFC 4202, October 2005.

   [RFC4203]  Kompella, K. and Y. Rekhter, "OSPF Extensions in Support
              of Generalized Multi-Protocol Label Switching (GMPLS)",
              RFC 4203, October 2005.

   [RFC5250]  Berger, L., Bryskin, I., Zinin, A., and R. Coltun, "The
              OSPF Opaque LSA Option", RFC 5250, July 2008.

   [RFC5340]  Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
              for IPv6", RFC 5340, July 2008.

   [RFC6001]

   [RFC4328]  Papadimitriou, D., Vigoureux, M., Shiomoto, K., Brungard,
              D., and JL. Le Roux, "Generalized MPLS Multi-Protocol Label
              Switching (GMPLS) Protocol Signaling Extensions for Multi-Layer and Multi-Region G.709 Optical
              Transport Networks (MLN/
              MRN)", Control", RFC 6001, October 2010. 4328, January 2006.

11.2.  Informative References

   [G.709]    ITU-T, "Interface for the Optical Transport Network
              (OTN)", G.709 Recommendation (and Amendment 1),
              February 2001.

   [G.709-v3]

   [G.709-2012]
              ITU-T, "Draft revised G.709, version 3", 4", consented
              by ITU-T on Oct 2009. in 2012.

   [OTN-FWK]  F.Zhang, D.Li, H.Li, S.Belotti, D.Ceccarelli, "Framework
              for GMPLS and PCE Control of G.709 Optical Transport
              networks, work in progress
              draft-ietf-ccamp-gmpls-g709-framework-11", November 2012.

   [OTN-INFO]
              S.Belotti, P.Grandi, D.Ceccarelli, D.Caviglia, F.Zhang,
              D.Li, "Information model for G.709 Optical Transport
              Networks (OTN), work in progress
              draft-ietf-ccamp-otn-g709-info-model-05", November 2012.

   [OTN-SIG]  F.Zhang, G.Zhang, S.Belotti, D.Ceccarelli, K.Pithewan,
              "Generalized Multi-Protocol Label Switching (GMPLS)
              Signaling Extensions for the evolving G.709 Optical
              Transport Networks Control, work in progress
              draft-ietf-ccamp-gmpls-signaling-g709v3-05",
              November 2012.

   [RFC2154]  Murphy, S., Badger, M., and B. Wellington, "OSPF with
              Digital Signatures", RFC 2154, June 1997.

   [RFC5920]  Fang, L., "Security Framework for MPLS and GMPLS
              Networks", RFC 5920, July 2010.

   [RFC6163]  Lee, Y., Bernstein, G., and W. Imajuku, "Framework for
              GMPLS and Path Computation Element (PCE) Control of
              Wavelength Switched Optical Networks (WSONs)", RFC 6163,
              April 2011.

   [RFC6566]  Lee, Y., Bernstein, G., Li, D., and G. Martinelli, "A
              Framework for the Control of Wavelength Switched Optical
              Networks (WSONs) with Impairments", RFC 6566, March 2012.

Authors' Addresses

   Daniele Ceccarelli (editor)
   Ericsson
   Via A. Negrone 1/A
   Genova - Sestri Ponente
   Italy

   Email: daniele.ceccarelli@ericsson.com

   Diego Caviglia
   Ericsson
   Via A. Negrone 1/A
   Genova - Sestri Ponente
   Italy

   Email: diego.caviglia@ericsson.com

   Fatai Zhang
   Huawei Technologies
   F3-5-B R&D Center, Huawei Base
   Shenzhen 518129 P.R.China  Bantian, Longgang District
   Phone: +86-755-28972912

   Email: zhangfatai@huawei.com

   Dan Li
   Huawei Technologies
   F3-5-B R&D Center, Huawei Base
   Shenzhen 518129 P.R.China  Bantian, Longgang District
   Phone: +86-755-28973237

   Email: danli@huawei.com
   Sergio Belotti
   Alcatel-Lucent
   Via Trento, 30
   Vimercate
   Italy

   Email: sergio.belotti@alcatel-lucent.com

   Pietro Vittorio Grandi
   Alcatel-Lucent
   Via Trento, 30
   Vimercate
   Italy

   Email: pietro_vittorio.grandi@alcatel-lucent.com

   Rajan Rao
   Infinera Corporation
   169, Java Drive
   Sunnyvale, CA-94089
   USA

   Email: rrao@infinera.com

   Khuzema Pithewan
   Infinera Corporation
   169, Java Drive
   Sunnyvale, CA-94089
   USA

   Email: kpithewan@infinera.com

   John E Drake
   Juniper

   Email: jdrake@juniper.net