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General Network Element Constraint Encoding for GMPLS Controlled Networks
draft-ietf-ccamp-general-constraint-encode-06

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This is an older version of an Internet-Draft that was ultimately published as RFC 7579.
Authors Greg M. Bernstein , Young Lee , Dan Li , Wataru Imajuku
Last updated 2011-12-13 (Latest revision 2011-05-25)
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draft-ietf-ccamp-general-constraint-encode-06
Network Working Group                                      G. Bernstein  
Internet Draft                                        Grotto Networking 
Intended status: Standards Track                                 Y. Lee  
Expires: June 2012                                                D. Li 
                                                                 Huawei 
                                                             W. Imajuku 
                                                                    NTT 
                                    
                                    
                                                      December 13, 2011 
                                      
     General Network Element Constraint Encoding for GMPLS Controlled 
                                 Networks 

             draft-ietf-ccamp-general-constraint-encode-06.txt 

Status of this Memo 

   This Internet-Draft is submitted to IETF in full conformance with the 
   provisions of BCP 78 and BCP 79. 

   Internet-Drafts are working documents of the Internet Engineering 
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   This Internet-Draft will expire on June 13, 2012. 

Copyright Notice 

   Copyright (c) 2011 IETF Trust and the persons identified as the 
   document authors.  All rights reserved.  

    

 
 
 
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   This document is subject to BCP 78 and the IETF Trust's Legal 
   Provisions Relating to IETF Documents 
   (http://trustee.ietf.org/license-info) in effect on the date of 
   publication of this document. Please review these documents 
   carefully, as they describe your rights and restrictions with respect 
   to this document.  Code Components extracted from this document must 
   include Simplified BSD License text as described in Section 4.e of 
   the Trust Legal Provisions and are provided without warranty as 
   described in the Simplified BSD License. 

Abstract 

   Generalized Multiprotocol Label Switching can be used to control a 
   wide variety of technologies. In some of these technologies network 
   elements and links may impose additional routing constraints such as 
   asymmetric switch connectivity, non-local label assignment, and label 
   range limitations on links.    

   This document provides efficient, protocol-agnostic encodings for 
   general information elements representing connectivity and label 
   constraints as well as label availability. It is intended that 
   protocol-specific documents will reference this memo to describe how 
   information is carried for specific uses. 

    

Conventions used in this document 

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 
   document are to be interpreted as described in RFC-2119 [RFC2119]. 

Table of Contents 

    
   1. Introduction...................................................3
      1.1. Node Switching Asymmetry Constraints......................3
      1.2. Non-Local Label Assignment Constraints....................4
      1.3. Change Log................................................5
   2. Encoding.......................................................5
      2.1. Link Set Field............................................5
      2.2. Label Set Field...........................................7
         2.2.1. Inclusive/Exclusive Label Lists......................8
         2.2.2. Inclusive/Exclusive Label Ranges.....................9
         2.2.3. Bitmap Label Set.....................................9
      2.3. Available Labels Sub-TLV.................................10
 
 
 
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      2.4. Shared Backup Labels Sub-TLV.............................11
      2.5. Connectivity Matrix Sub-TLV..............................11
      2.6. Port Label Restriction sub-TLV...........................12
         2.6.1. SIMPLE_LABEL........................................13
         2.6.2. CHANNEL_COUNT.......................................14
         2.6.3. LABEL_RANGE1........................................14
         2.6.4. SIMPLE_LABEL & CHANNEL_COUNT........................15
         2.6.5. Link Label Exclusivity..............................15
   3. Security Considerations.......................................15
   4. IANA Considerations...........................................16
   5. Acknowledgments...............................................16
   APPENDIX A: Encoding Examples....................................17
      A.1. Link Set Field...........................................17
      A.2. Label Set Field..........................................17
      A.3. Connectivity Matrix Sub-TLV..............................18
      A.4. Connectivity Matrix with Bi-directional Symmetry.........21
   6. References....................................................24
      6.1. Normative References.....................................24
      6.2. Informative References...................................24
   7. Contributors..................................................25
   Authors' Addresses...............................................26
   Intellectual Property Statement..................................27
   Disclaimer of Validity...........................................27
    
1. Introduction 

   Some data plane technologies that wish to make use of a GMPLS control 
   plane contain additional constraints on switching capability and 
   label assignment. In addition, some of these technologies must 
   perform non-local label assignment based on the nature of the 
   technology, e.g., wavelength continuity constraint in WSON [WSON-
   Frame]. Such constraints can lead to the requirement for link by link 
   label availability in path computation and label assignment. 

   This document provides efficient encodings of information needed by 
   the routing and label assignment process in technologies such as WSON 
   and are potentially applicable to a wider range of technologies. Such 
   encodings can be used to extend GMPLS signaling and routing 
   protocols. In addition these encodings could be used by other 
   mechanisms to convey this same information to a path computation 
   element (PCE). 

1.1. Node Switching Asymmetry Constraints 

   For some network elements the ability of a signal or packet on a 
   particular ingress port to reach a particular egress port may be 
 
 
 
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   limited. In addition, in some network elements the connectivity 
   between some ingress ports and egress ports may be fixed, e.g., a 
   simple multiplexer. To take into account such constraints during path 
   computation we model this aspect of a network element via a 
   connectivity matrix. 

   The connectivity matrix (ConnectivityMatrix) represents either the 
   potential connectivity matrix for asymmetric switches or fixed 
   connectivity for an asymmetric device such as a multiplexer. Note 
   that this matrix does not represent any particular internal blocking 
   behavior but indicates which ingress ports and labels (e.g., 
   wavelengths) could possibly be connected to a particular output port. 
   Representing internal state dependent blocking for a node is beyond 
   the scope of this document and due to it's highly implementation 
   dependent nature would most likely not be subject to standardization 
   in the future. The connectivity matrix is a conceptual M by N matrix 
   representing the potential switched or fixed connectivity, where M 
   represents the number of ingress ports and N the number of egress 
   ports.  

    

1.2. Non-Local Label Assignment Constraints 

   If the nature of the equipment involved in a network results in a 
   requirement for non-local label assignment we can have constraints 
   based on limits imposed by the ports themselves and those that are 
   implied by the current label usage. Note that constraints such as 
   these only become important when label assignment has a non-local 
   character. For example in MPLS an LSR may have a limited range of 
   labels available for use on an egress port and a set of labels 
   already in use on that port and hence unavailable for use. This 
   information, however, does not need to be shared unless there is some 
   limitation on the LSR's label swapping ability. For example if a TDM 
   node lacks the ability to perform time-slot interchange or a WSON 
   lacks the ability to perform wavelength conversion then the label 
   assignment process is not local to a single node and it may be 
   advantageous to share the label assignment constraint information for 
   use in path computation. 

   Port label restrictions (PortLabelRestriction) model the label 
   restrictions that the network element (node) and link may impose on a 
   port. These restrictions tell us what labels may or may not be used 
   on a link and are intended to be relatively static. More dynamic 
   information is contained in the information on available labels. Port 
   label restrictions are specified relative to the port in general or 
 
 
 
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   to a specific connectivity matrix for increased modeling flexibility. 
   Reference [Switch] gives an example where both switch and fixed 
   connectivity matrices are used and both types of constraints occur on 
   the same port. 

1.3. Change Log 

   Changes from 03 version: 

   (a)Removed informational BNF from section 1. 

   (b) Removed section on "Extension Encoding Usage Recommendations" 

   Changes from 04,05 versions: 

   No changes just refreshed document that was expiring. 

2. Encoding 

   A type-length-value (TLV) encoding of the general connectivity and 
   label restrictions and availability extensions is given in this 
   section. This encoding is designed to be suitable for use in the 
   GMPLS routing protocols OSPF [RFC4203] and IS-IS [RFC5307] and in the 
   PCE protocol PCEP [PCEP]. Note that the information distributed in 
   [RFC4203] and [RFC5307] is arranged via the nesting of sub-TLVs 
   within TLVs and this document makes use of such constructs. First, 
   however we define two general purpose fields that will be used 
   repeatedly in the subsequent TLVs. 

    

2.1. Link Set Field 

   We will frequently need to describe properties of groups of links. To 
   do so efficiently we can make use of a link set concept similar to 
   the label set concept of [RFC3471]. This Link Set Field is used in 
   the <ConnectivityMatrix> sub-TLV, which is defined in Section 2.5.  
   The information carried in a Link Set is defined by: 

 
 
 
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       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 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
      |    Action     |Dir|  Format   |         Length                | 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
      |                       Link Identifier 1                       | 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
      :                               :                               : 
      :                               :                               : 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
      |                       Link Identifier N                       | 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     

     Action: 8 bits 

         0 - Inclusive List  

   Indicates that one or more link identifiers are included in the Link 
   Set. Each identifies a separate link that is part of the set. 

         1 - Inclusive Range 

   Indicates that the Link Set defines a range of links.  It contains 
   two link identifiers. The first identifier indicates the start of the 
   range (inclusive). The second identifier indicates the end of the 
   range (inclusive). All links with numeric values between the bounds 
   are considered to be part of the set. A value of zero in either 
   position indicates that there is no bound on the corresponding 
   portion of the range. Note that the Action field can be set to 
   0x02(Inclusive Range) only when unnumbered link identifier is used. 

     Dir: Directionality of the Link Set (2 bits) 

        0 -- bidirectional 
         1 -- ingress  

         2 -- egress 

   For example in optical networks we think in terms of unidirectional 
   as well as bidirectional links. For example, label restrictions or 
   connectivity may be different for an ingress port, than for its 
   "companion" egress port if one exists. Note that "interfaces" such as 
   those discussed in the Interfaces MIB [RFC2863] are assumed to be 

 
 
 
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   bidirectional. This also applies to the links advertised in various 
   link state routing protocols. 

     Format: The format of the link identifier (6 bits) 

         0 -- Link Local Identifier  

   Indicates that the links in the Link Set are identified by link local 
   identifiers. All link local identifiers are supplied in the context 
   of the advertising node. 

         1 -- Local Interface IPv4 Address  

        2 -- Local Interface IPv6 Address 

   Indicates that the links in the Link Set are identified by Local 
   Interface IP Address. All Local Interface IP Address are supplied in 
   the context of the advertising node. 

         Others TBD. 

   Note that all link identifiers in the same list must be of the same 
   type. 

     Length: 16 bits 

   This field indicates the total length in bytes of the Link Set field. 

     Link Identifier: length is dependent on the link format 

   The link identifier represents the port which is being described 
   either for connectivity or label restrictions. This can be the link 
   local identifier of [RFC4202], GMPLS routing, [RFC4203] GMPLS OSPF 
   routing, and [RFC5307] IS-IS GMPLS routing. The use of the link local 
   identifier format can result in more compact encodings when the 
   assignments are done in a reasonable fashion. 

2.2. Label Set Field 

   Label Set Field is used within the <AvailableLabels> sub-TLV or the 
   <SharedBackupLabels> sub-TLV, which is defined in Section 2.3.  and 
   2.4. , respectively.  

   The general format for a label set is given below. This format uses 
   the Action concept from [RFC3471] with an additional Action to define 

 
 
 
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   a "bit map" type of label set. The second 32 bit field is a base 
   label used as a starting point in many of the specific formats.  

      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     | Action|    Num Labels         |          Length               | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                          Base Label                           | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |     Additional fields as necessary per action                 | 
     | 
    
    

   Action: 

         0 - Inclusive List 

         1 - Exclusive List 

         2 - Inclusive Range 

         3 - Exclusive Range 

         4 - Bitmap Set 

   Num Labels is only meaningful for Action value of 4 (Bitmap Set). It 
   indicates the number of labels represented by the bit map. See more 
   detail in section 3.2.3.  

   Length is the length in bytes of the entire field. 

   2.2.1. Inclusive/Exclusive Label Lists 

   In the case of the inclusive/exclusive lists the wavelength set 
   format is given by: 

 
 
 
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      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |0 or 1 | Num Labels (not used) |          Length               | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                         Base Label                            | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+      
     :                                                               : 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                         Last  Label                           | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   Where:  

   Num Labels is not used in this particular format since the Length 
   parameter is sufficient to determine the number of labels in the 
   list. 

   2.2.2. Inclusive/Exclusive Label Ranges 

   In the case of inclusive/exclusive ranges the label set format is 
   given by: 

      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |2 or 3 | Num Labels(not used)  |             Length            | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                    Start Label                                | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     End Label                                 | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 

    

   Note that the start and end label must in some sense "compatible" in 
   the technology being used.  

   2.2.3. Bitmap Label Set 

   In the case of Action = 4, the bitmap the label set format is given 
   by: 

 
 
 
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      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  4    |   Num Labels          |             Length            | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                         Base Label                            | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |    Bit Map Word #1 (Lowest numerical labels)                  | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     :                                                               : 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |    Bit Map Word #N (Highest numerical labels)                 | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   Where Num Labels in this case tells us the number of labels 
   represented by the bit map. Each bit in the bit map represents a 
   particular label with a value of 1/0 indicating whether the label is 
   in the set or not. Bit position zero represents the lowest label and 
   corresponds to the base label, while each succeeding bit position 
   represents the next label logically above the previous. 

   The size of the bit map is Num Label bits, but the bit map is padded 
   out to a full multiple of 32 bits so that the TLV is a multiple of 
   four bytes. Bits that do not represent labels (i.e., those in 
   positions (Num Labels) and beyond SHOULD be set to zero and MUST be 
   ignored. 

2.3. Available Labels Sub-TLV 

   To indicate the labels available for use on a link the Available 
   Labels sub-TLV consists of a single variable length label set field 
   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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                           Label Set Field                     | 
     :                                                               : 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   Note that Label Set Field is defined in Section 3.2.  

    

 
 
 
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2.4. Shared Backup Labels Sub-TLV 

   To indicate the labels available for shared backup use on a link the 
   Shared Backup Labels sub-TLV consists of a single variable length 
   label set field 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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Label Set Field                           | 
     :                                                               : 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

    

2.5. Connectivity Matrix Sub-TLV 

   The Connectivity Matrix represents how ingress ports are connected to 
   egress ports for network elements. The switch and fixed connectivity 
   matrices can be compactly represented in terms of a minimal list of 
   ingress and egress port set pairs that have mutual connectivity. As 
   described in [Switch] such a minimal list representation leads 
   naturally to a graph representation for path computation purposes 
   that involves the fewest additional nodes and links. 

   A TLV encoding of this list of link set pairs 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 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
      | Connectivity  |   MatrixID    |             Reserved          | 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
      |                         Link Set A #1                         | 
      :                               :                               : 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
      |                         Link Set B #1                         : 
      :                               :                               : 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
      |                       Additional Link set pairs as needed     | 
      :                     to specify connectivity                   : 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   Where  

 
 
 
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   Connectivity is the device type.  

         0 -- the device is fixed 

         1 -- the device is switched(e.g., ROADM/OXC) 

   MatrixID represents the ID of the connectivity matrix and is an 8 bit 
   integer. The value of 0xFF is reserved for use with port wavelength 
   constraints and should not be used to identify a connectivity matrix. 

   Link Set A #1 and Link Set B #1 together represent a pair of link 
   sets. There are two permitted combinations for the link set field 
   parameter "dir" for Link Set A and B pairs: 

   o  Link Set A dir=ingress, Link Set B dir=egress 

     The meaning of the pair of link sets A and B in this case is that 
     any signal that ingresses a link in set A can be potentially 
     switched out of an egress link in set B. 

   o  Link Set A dir=bidirectional, Link Set B dir=bidirectional 

      The meaning of the pair of link sets A and B in this case is that 
      any signal that ingresses on the links in set A can potentially 
      egress on a link in set B, and any ingress signal on the links in 
      set B can potentially egress on a link in set A. 

   See Appendix A for both types of encodings as applied to a ROADM 
   example. 

    
2.6. Port Label Restriction sub-TLV 

   Port Label Restriction tells us what labels may or may not be used on 
   a link.  

   The port label restriction of section 1.2.  can be encoded as a sub-
   TLV as follows. More than one of these sub-TLVs may be needed to 
   fully specify a complex port constraint. When more than one of these 
   sub-TLVs are present the resulting restriction is the intersection of 
   the restrictions expressed in each sub-TLV. To indicate that a 
   restriction applies to the port in general and not to a specific 
   connectivity matrix use the reserved value of 0xFF for the MatrixID. 

 
 
 
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      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |   MatrixID    |  RestrictionType |      Reserved/Parameter    | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |     Additional Restriction Parameters per RestrictionType    | 
     :                                                               : 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   Where: 

   MatrixID: either is the value in the corresponding Connectivity 
   Matrix sub-TLV or takes the value OxFF to indicate the restriction 
   applies to the port regardless of any Connectivity Matrix. 

   RestrictionType can take the following values and meanings: 

         0: SIMPLE_LABEL  (Simple label selective restriction)  

         1: CHANNEL_COUNT (Channel count restriction) 

         2: LABEL_RANGE1 (Label range device with a movable center label 
         and width)  

         3: SIMPLE_LABEL & CHANNEL_COUNT (Combination of SIMPLE_LABEL 
         and CHANNEL_COUNT restriction. The accompanying label set and 
         channel count indicate labels permitted on the port and the 
         maximum number of channels that can be simultaneously used on 
         the port) 

         4: LINK_LABEL_EXCLUSIVITY (A label may be used at most once 
         amongst a set of specified ports) 

   2.6.1. SIMPLE_LABEL 

   In the case of the SIMPLE_LABEL the GeneralPortRestrictions (or 
   MatrixSpecificRestrictions) format is given by: 

 
 
 
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      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     | MatrixID      | RstType = 0   |             Reserved          | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                        Label Set Field                  | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   In this case the accompanying label set indicates the labels 
   permitted on the port. 

    
   2.6.2. CHANNEL_COUNT 

   In the case of the CHANNEL_COUNT the format is given by: 

      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     | MatrixID      | RstType = 1   |        MaxNumChannels         | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
   In this case the accompanying MaxNumChannels indicates the maximum 
   number of channels (labels) that can be simultaneously used on the 
   port/matrix. 

    
   2.6.3. LABEL_RANGE1 

   In the case of the LABEL_RANGE1 the GeneralPortRestrictions (or 
   MatrixSpecificRestrictions) format is given by: 

    
      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     | MatrixID      | RstType = 2   |     MaxLabelRange             | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                        Label Set Field                        | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
   In this case the accompanying MaxLabelRange indicates the maximum 
   range of the labels. The corresponding label set is used to indicate 
   the overall label range. Specific center label information can be 
   obtained from dynamic label in use information. It is assumed that 
 
 
 
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   both center label and range tuning can be done without causing faults 
   to existing signals. 

    
   2.6.4. SIMPLE_LABEL & CHANNEL_COUNT 

   In the case of the SIMPLE_LABEL & CHANNEL_COUNT the format is given 
   by: 

      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     | MatrixID      | RstType = 3   |        MaxNumChannels         | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Label Set Field                     | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   In this case the accompanying label set and MaxNumChannels indicate 
   labels permitted on the port and the maximum number of labels that 
   can be simultaneously used on the port. 

   2.6.5. Link Label Exclusivity 

   In the case of the SIMPLE_LABEL & CHANNEL_COUNT the format is given 
   by: 

      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     | MatrixID      | RstType = 4   |        Reserved               | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Set Field                            | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   In this case the accompanying port set indicate that a label may be 
   used at most once among the ports in the link set field.  

    

3. Security Considerations 

   This document defines protocol-independent encodings for WSON 
   information and does not introduce any security issues. 

 
 
 
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   However, other documents that make use of these encodings within 
   protocol extensions need to consider the issues and risks associated 
   with, inspection, interception, modification, or spoofing of any of 
   this information. It is expected that any such documents will 
   describe the necessary security measures to provide adequate 
   protection. 

4. IANA Considerations 

   TBD. Once our approach is finalized we may need identifiers for the 
   various TLVs and sub-TLVs. 

5. Acknowledgments 

   This document was prepared using 2-Word-v2.0.template.dot. 

 
 
 
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APPENDIX A: Encoding Examples 

   Here we give examples of the general encoding extensions applied to 
   some simple ROADM network elements and links. 

A.1. Link Set Field 

   Suppose that we wish to describe a set of ingress ports that are have 
   link local identifiers number 3 through 42. In the link set field we 
   set the Action = 1 to denote an inclusive range; the Dir = 1 to 
   denote ingress links; and, the Format = 0 to denote link local 
   identifiers. In particular we have: 

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=1     |0 1|0 0 0 0 0 0|             Length = 12       | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #3                | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #42               | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

A.2. Label Set Field 

   Example: 

   A 40 channel C-Band DWDM system with 100GHz spacing with lowest 
   frequency 192.0THz (1561.4nm) and highest frequency 195.9THz 
   (1530.3nm). These frequencies correspond to n = -11, and n = 28 
   respectively. Now suppose the following channels are available: 

   Frequency (THz)    n Value      bit map position 
   -------------------------------------------------- 
      192.0             -11               0 
      192.5              -6               5 
      193.1               0              11 
      193.9               8              19 
      194.0               9              20 
      195.2              21              32 
      195.8              27              38 
    
   With the Grid value set to indicate an ITU-T G.694.1 DWDM grid, C.S. 
   set to indicate 100GHz this lambda bit map set would then be encoded 
   as follows: 

 
 
 
 
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      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  4    | Num Wavelengths = 40  |    Length = 16 bytes          | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |Grid |  C.S. |      Reserved   | n  for lowest frequency = -11 | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |1 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0| 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |1 0 0 0 0 0 1 0|   Not used in 40 Channel system (all zeros)   |  
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 

   To encode this same set as an inclusive list we would have: 

      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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  0    | Num Wavelengths = 40  |    Length = 20 bytes          | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |Grid |  C.S. |      Reserved   | n  for lowest frequency = -11 | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |Grid |  C.S. |      Reserved   | n  for lowest frequency = -6  | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |Grid |  C.S. |      Reserved   | n  for lowest frequency = -0  | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |Grid |  C.S. |      Reserved   | n  for lowest frequency = 8   | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |Grid |  C.S. |      Reserved   | n  for lowest frequency = 9   | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |Grid |  C.S. |      Reserved   | n  for lowest frequency = 21  | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |Grid |  C.S. |      Reserved   | n  for lowest frequency = 27  | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
 

    

A.3. Connectivity Matrix Sub-TLV 

   Example: 

   Suppose we have a typical 2-degree 40 channel ROADM. In addition to 
   its two line side ports it has 80 add and 80 drop ports. The picture 
   below illustrates how a typical 2-degree ROADM system that works with 
   bi-directional fiber pairs is a highly asymmetrical system composed 
   of two unidirectional ROADM subsystems.  
 
 
 
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                         (Tributary) Ports #3-#42 
                     Ingress added to    Egress dropped from 
                     West Line Egress    East Line Ingress 
                           vvvvv          ^^^^^ 
                          | |||.|       | |||.| 
                    +-----| |||.|--------| |||.|------+ 
                    |    +----------------------+     | 
                    |    |                      |     | 
        Egress      |    | Unidirectional ROADM |     |    Ingress 
   -----------------+    |                      |     +-------------- 
   <=====================|                      |===================< 
   -----------------+    +----------------------+     +-------------- 
                    |                                 | 
        Port #1     |                                 |   Port #2 
   (West Line Side) |                                 |(East Line Side) 
   -----------------+    +----------------------+     +-------------- 
   >=====================|                      |===================> 
   -----------------+    | Unidirectional ROADM |     +-------------- 
        Ingress     |    |                      |     |    Egress 
                    |    |              _       |     | 
                    |    +----------------------+     | 
                    +-----| |||.|--------| |||.|------+ 
                          | |||.|        | |||.| 
                           vvvvv          ^^^^^ 
                     (Tributary) Ports #43-#82 
                Egress dropped from    Ingress added to 
                West Line ingress      East Line egress 
    

   Referring to the figure we see that the ingress direction of ports 
   #3-#42 (add ports) can only connect to the egress on port #1. While 
   the ingress side of port #2 (line side) can only connect to the 
   egress on ports #3-#42 (drop) and to the egress on port #1 (pass 
   through). Similarly, the ingress direction of ports #43-#82 can only 
   connect to the egress on port #2 (line). While the ingress direction 
   of port #1 can only connect to the egress on ports #43-#82 (drop) or 
   port #2 (pass through). We can now represent this potential 
   connectivity matrix as follows. This representation uses only 30 32-
   bit words. 

 
 
 
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       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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |    Conn = 1   |    MatrixID   |      Reserved                 |1 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                          Note: adds to line 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=1     |0 1|0 0 0 0 0 0|          Length = 12          |2 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #3                |3 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #42               |4 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |1 0|0 0 0 0 0 0|          Length = 8           |5 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #1                |6 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                       Note: line to drops 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |0 1|0 0 0 0 0 0|          Length = 8           |7 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #2                |8 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=1     |1 0|0 0 0 0 0 0|          Length = 12          |9 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #3                |10 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #42               |11 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                       Note: line to line  
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |0 1|0 0 0 0 0 0|          Length = 8           |12 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #2                |13 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |1 0|0 0 0 0 0 0|          Length = 8           |14 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #1                |15 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                                Note: adds to line  
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=1     |0 1|0 0 0 0 0 0|          Length = 12          |16 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #43               |17 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
 
 
 
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     |                     Link Local Identifier = #82               |18 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |1 0|0 0 0 0 0 0|          Length = 8           |19  
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #2                |20 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                       Note: line to drops 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |0 1|0 0 0 0 0 0||          Length = 8          |21 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #1                |22 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=1     |1 0|0 0 0 0 0 0|          Length = 12          |23 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #43               |24 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #82               |25 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                       Note: line to line  
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |0 1|0 0 0 0 0 0|          Length = 8           |26 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #1                |27 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |1 0|0 0 0 0 0 0|          Length = 8           |28 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #2                |30 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
    
A.4. Connectivity Matrix with Bi-directional Symmetry 

   If one has the ability to renumber the ports of the previous example 
   as shown in the next figure then we can take advantage of the bi-
   directional symmetry and use bi-directional encoding of the 
   connectivity matrix. Note that we set dir=bidirectional in the link 
   set fields. 

 
 
 
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                                (Tributary) 
                     Ports #3-42         Ports #43-82 
                     West Line Egress    East Line Ingress 
                           vvvvv          ^^^^^ 
                          | |||.|        | |||.| 
                    +-----| |||.|--------| |||.|------+ 
                    |    +----------------------+     | 
                    |    |                      |     | 
        Egress      |    | Unidirectional ROADM |     |    Ingress 
   -----------------+    |                      |     +-------------- 
   <=====================|                      |===================< 
   -----------------+    +----------------------+     +-------------- 
                    |                                 | 
        Port #1     |                                 |   Port #2 
   (West Line Side) |                                 |(East Line Side) 
   -----------------+    +----------------------+     +-------------- 
   >=====================|                      |===================> 
   -----------------+    | Unidirectional ROADM |     +-------------- 
        Ingress     |    |                      |     |    Egress 
                    |    |              _       |     | 
                    |    +----------------------+     | 
                    +-----| |||.|--------| |||.|------+ 
                          | |||.|        | |||.| 
                           vvvvv          ^^^^^ 
                     Ports #3-#42         Ports #43-82 
                Egress dropped from    Ingress added to 
                West Line ingress      East Line egress 
    

 

 
 
 
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       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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |    Conn = 1   |    MatrixID   |      Reserved                 |1 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                          Add/Drops #3-42 to Line side #1 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=1     |0 0|0 0 0 0 0 0|          Length = 12          |2 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #3                |3 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #42               |4 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |0 0|0 0 0 0 0 0|          Length = 8           |5 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #1                |6 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                       Note: line #2 to add/drops #43-82 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |0 0|0 0 0 0 0 0|          Length = 8           |7 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #2                |8 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=1     |0 0|0 0 0 0 0 0|          Length = 12          |9 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #43               |10 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #82               |11 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                       Note: line to line  
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |0 0|0 0 0 0 0 0|          Length = 8           |12 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #1                |13 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |  Action=0     |0 0|0 0 0 0 0 0|          Length = 8           |14 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |                     Link Local Identifier = #2                |15 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
 

 
 
 
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6. References 

6.1. Normative References 

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

   [RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group 
             MIB", RFC 2863, June 2000. 

   [RFC3471] Berger, L., "Generalized Multi-Protocol Label Switching 
             (GMPLS) Signaling Functional Description", RFC 3471, 
             January 2003. 

   [G.694.1] ITU-T Recommendation G.694.1, "Spectral grids for WDM 
             applications: DWDM frequency grid", June, 2002. 

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

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

    

6.2. Informative References 

   [G.694.1] ITU-T Recommendation G.694.1, Spectral grids for WDM 
             applications: DWDM frequency grid, June 2002. 

   [G.694.2] ITU-T Recommendation G.694.2, Spectral grids for WDM 
             applications: CWDM wavelength grid, December 2003. 

   [RFC5307] Kompella, K., Ed., and Y. Rekhter, Ed., "IS-IS Extensions 
             in Support of Generalized Multi-Protocol Label Switching 
             (GMPLS)", RFC 5307, October 2008. 

    

 
 
 
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   [Switch] G. Bernstein, Y. Lee, A. Gavler, J. Martensson, " Modeling 
         WDM Wavelength Switching Systems for Use in GMPLS and Automated 
         Path Computation", Journal of Optical Communications and 
         Networking, vol. 1, June, 2009, pp. 187-195. 

   [PCEP]    Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation 
             Element (PCE) communication Protocol (PCEP) - Version 1", 
             RFC5440. 

    

    

7. Contributors 

   Diego Caviglia  
   Ericsson 
   Via A. Negrone 1/A 16153 
   Genoa Italy 
    
   Phone: +39 010 600 3736 
   Email: diego.caviglia@(marconi.com, ericsson.com) 
    
   Anders Gavler 
   Acreo AB 
   Electrum 236 
   SE - 164 40 Kista Sweden 
    
   Email: Anders.Gavler@acreo.se 
    
   Jonas Martensson 
   Acreo AB 
   Electrum 236 
   SE - 164 40 Kista, Sweden 
    
   Email: Jonas.Martensson@acreo.se 
    
   Itaru Nishioka 
   NEC Corp. 
   1753 Simonumabe, Nakahara-ku, Kawasaki, Kanagawa 211-8666 
   Japan 
    
   Phone: +81 44 396 3287 
   Email: i-nishioka@cb.jp.nec.com 
    

 
 
 
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Authors' Addresses 

   Greg M. Bernstein (ed.) 
   Grotto Networking 
   Fremont California, USA 
       
   Phone: (510) 573-2237 
   Email: gregb@grotto-networking.com 
    

   Young Lee (ed.) 
   Huawei Technologies 
   1700 Alma Drive, Suite 100 
   Plano, TX 75075 
   USA 
    
   Phone: (972) 509-5599 (x2240) 
   Email: ylee@huawei.com 
    

   Dan Li  
   Huawei Technologies Co., Ltd.  
   F3-5-B R&D Center, Huawei Base,  
   Bantian, Longgang District  
   Shenzhen 518129 P.R.China  
    
   Phone: +86-755-28973237 
   Email: danli@huawei.com 
    
   Wataru Imajuku 
   NTT Network Innovation Labs 
   1-1 Hikari-no-oka, Yokosuka, Kanagawa 
   Japan 
    
   Phone: +81-(46) 859-4315 
   Email: imajuku.wataru@lab.ntt.co.jp 
    
 

 
 
 
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   Jianrui Han  
   Huawei Technologies Co., Ltd.  
   F3-5-B R&D Center, Huawei Base,  
   Bantian, Longgang District  
   Shenzhen 518129 P.R.China  
    
   Phone: +86-755-28972916 
   Email: hanjianrui@huawei.com 
 

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Acknowledgment 

   Funding for the RFC Editor function is currently provided by the 
   Internet Society. 

    

 
 
 
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