One document matched: draft-ceccarelli-ccamp-gmpls-ospf-g709-00.txt


Network Working Group                                       D.Ceccarelli  
Internet Draft                                                D.Caviglia 
Category: Standards Track                                       Ericsson         
                                                             Fatai Zhang 
                                                                  Dan Li 
                                                                  Huawei 
Expires: April 2010                                     October 16, 2009 
 
                                       


    Traffic Engineering Extensions to OSPF for Generalized MPLS (GMPLS) 
                  Control of Evolutive G.709 OTN Networks 


               draft-ceccarelli-ccamp-gmpls-ospf-g709-00.txt 


Status of this Memo 

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   This Internet-Draft will expire on March 24, 2010. 

    

Abstract 
 
   This document describes OSPF routing protocol extensions to support   
   the evolutive Optical Transport Networks (OTN) under the control of 
   Generalized MPLS (GMPLS).  
 
 
 
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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 [RFC2119]. 

Table of Contents 

    
   1. Introduction..................................................2 
   2. Terminology...................................................3 
   3. Overview of the Evolutive G.709...............................3 
   4. G.709 Digital Layer TE Information............................5 
      4.1. Tributary Slot type......................................5 
      4.2. TE link type.............................................6 
      4.3. LO ODU signal type.......................................6 
      4.4. TE link Total Bandwidth..................................7 
      4.5. TE link Unreserved Bandwidth.............................7 
      4.6. Maximum LSP Bandwidth....................................7 
   5. OSPF extensions...............................................8 
      5.1. Extensions to Interface Switching Capability Descriptor..8 
   6. Compatibility Considerations.................................11 
   7. Example......................................................11 
   8. Security Considerations......................................13 
   9. IANA Considerations..........................................13 
   10. Acknowledgments.............................................13 
   11. References..................................................13 
      11.1. Normative References...................................13 
      11.2. Informative References.................................14 
   12. Authors' Addresses..........................................14 
   13. Contributors................................................15 
 
 
1. Introduction 

   Per OSPF, an Opaque LSA (Link State Advertisements) carrying 
   application-specific information can be generated and advertised to 
   other nodes following the flooding mechanism defined in [RFC 2370]. 
   Three types of opaque LSA are defined, i.e. type 9 - link-local 
   flooding scope, type 10 - area-local flooding scope, type 11 - AS 
   flooding scope.  

   Traffic Engineering (TE) LSA using type 10 of opaque LSA is defined 
   in [RFC 3630] for TE purpose. This type of LSA is composed of a 
   standard LSA header and a payload including one top-level TLV 
   (Type/Length/Value triplet) and possible several nested sub-TLVs. 

 
 
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   RFC [3630]defines two top-level TLVs: Router Address TLV and Link TLV; 
   and nine possible sub-TLVs for the Link TLV, used to carry link 
   related TE information.  

   The Link type sub-TLVs are enhanced by [RFC 4203] in order to support 
   GMPLS networks and related specific link information.  

   In GMPLS networks, each node generates TE LSAs to advertise its TE 
   information and capabilities (link-specific, or node-specific), 
   through the network. The TE information carried in the LSAs are 
   collected by the other nodes of the networks and stored into their 
   local Traffic Engineering Databases (TED).  

   In the GMPLS based G.709 Optical Transport Networks (OTNs), in order 
   to automatically establish ODUk connections through GMPLS RSVP-TE 
   signaling, routing is the foundation.  

   OTN networks provide flexible and various multiplexing relationships 
   (e.g., ODUj multiplexed into ODUk (j<k)), two different tributary 
   slots for ODUk (K=1, 2, 3)and ODUflex signal type, which is being 
   standardized in ITU-T. In order to present this information in the 
   routing process, the OSPF protocol needs to be extended.  

   This document describes OSPF routing protocol extensions to support 
   the evolutive OTNs under the control of GMPLS.  

   Note that the routing information for Optical Channel Layer (OCh) 
   (i.e., wavelength) is out of the scope. Please refer to [WSON-Frame] 
   for further information. 

2. 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]. 

3. Overview of the Evolutive G.709 

   The traditional OTN specification [G709] describes the Optical 
   Transport Hierarchy (OTH) and introduces three types of ODU (Optical 
   Channel Data Unit) signal (i.e., ODU1, ODU2 and ODU3). The ODUj can 
   be mapped into one or more Tributary Slots (with granularity of 
   2.5Gbps) of OPUk (Optical Channel Payload Unit-k) where j<k. The ODUj 
   can also be mapped into OTUj (Optical Channel Transport Unit-j, j=1, 
   2 or 3) directly. 

 
 
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   Recent revisions of ITU-T Recommendation G.709 have introduced new 
   features for OTNs:ODU0, ODU4, ODU2e, ODU3e1, ODU3e2 and ODUflex. The 
   new features for the evolutive OTNs are described in separate ITU-T 
   documents. ODU0, ODU2e and ODU4 ODUflex are described in [G709-V3]. 
   ODU3e1 and ODU3e2 are described in [Gsup43].  

   The ITU-T documents also define the new multiplexing hierarchy for 
   the evolutive OTN. In this multiplexing hierarchy, LO (Lower Order) 
   ODUj can be mapped into an OTUj, or multiplexed into an HO (Higher 
   Order) ODUk (where j<k) occupying several TSs (Tributary Slots). 

   In the case of LO ODUj mapping into OTUj, the following mappings are 
   defined: 

      o ODU1 into OTU1 mapping 

      o ODU2 into OTU2 mapping 

      o ODU3 into OTU3 mapping 

      o ODU4 into OTU4 mapping 

      o ODU2e into OTU2e mapping 

   In the case of LO ODUj multiplexing into HO ODUk, a new Tributary 
   Slot granularity (i.e., 1.25Gbps) is introduced in [G709-V3]. For the 
   evolutive OTN, the multiplexing of ODUj (j = 0, 1, 2, 2e, 3, flex) 
   into an ODUk (k > j) signal can be depicted as follows: 

       -  ODU0 into ODU1 multiplexing (with 1,25Gbps TS granularity) 

       -  ODU0, ODU1, ODUflex into ODU2 multiplexing (with 1.25Gbps TS      
          granularity) 

       -  ODU1 into ODU2 multiplexing (with 2.5Gbps TS granularity) 

       -  ODU0, ODU1, ODU2, ODU2e and ODUflex into ODU3 multiplexing 
         (with 1.25Gbps TS granularity) 

       -  ODU1, ODU2 into ODU3 multiplexing (with 2.5Gbps TS granularity) 

       -  ODU0, ODU1, ODU2, ODU2e, ODU3 and ODUflex into ODU4 
          multiplexing (with 1.25Gbps TS granularity) 

       - ODU2e into ODU3e1 multiplexing (with 2.5Gbps TS granularity) 

       - ODU2e into ODU3e2 multiplexing (with 1.25Gbps TS granularity) 
 
 
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   In order to be backward compatible with the 2.5Gbps TS defined in 
   [G709-V3], both the 2.5Gbps TS and the 1.25Gbps TS can be used in the 
   two cases listed below: 

      o ODU1 into ODU2 multiplexing 

      o ODU1 and ODU2 into ODU3 multiplexing 

   From the link perspective, it can only work under one TS type. For 
   example, if the both ends (or interfaces) of the link can support 
   2.5Gbps TS and 1.25Gbps TS, then it will work under 2.5Gbps TS or 
   1.25Gbps TS. If one end can support 1.25Gbps TS, and another end can 
   support 2.5Gbps TS, the end with 1.25Gbps TS MUST adopt a 2.5Gbps TS). 
    
4. G.709 Digital Layer TE Information 

   This document only considers the TE information needed for LO ODU 
   path computation. WSON TE information is out of scope. Please refer 
   to [WSON-OSPF] for more information about WSON routing information. 

   From the perspective of [G709-V3], there are two types of LO ODU:  

   (1) A LO ODUk mapped into an OTUk. In this case, the server layer of 
   this LO ODU is an OTUk. For example, if a STM-16 signal is 
   encapsulated into ODU1, and then ODU1 is mapped into OTU1, the ODU1 
   is LO ODU. 

   (2) A LO ODUj multiplexed into a HO (Higher Order) ODUk (j < k) 
   occupying several TSs. In this case, the server layer of this LO ODU 
   is a HO ODUk. For example, if ODU1 is multiplexed into ODU2, and ODU2 
   is mapped into OTU2, the ODU1 is LO ODU and ODU2 is HO ODU. 

   In order to compute a suitable path the PCE (centralized or 
   distributed) need a set of data that should be advertised by the 
   routing protocol. In the following sections each type of data is 
   listed and analyzed, while the possible values are shown in section 5. 

4.1. Tributary Slot type 

   There are two types of TS defined in the ITU-T recommendations, and 
   from the link perspective, it can only work under one TS type. For 
   example, if the both ends (or interfaces) of a link can support 
   2.5Gbps TS or 1.25Gbps TS, then it will work under 2.5Gbps TS or 
   1.25Gbps TS. If one end can support 1.25Gbps TS, and another end can 
   support 2.5Gbps TS, the end with 1.25Gbps TS should adopt the 2.5Gbps 
   TS). 
 
 
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   In addition, the bandwidth accounting depends on the type of TS. 
   Therefore, the type of the TS should be known during LO ODU path 
   computation. 

4.2. TE link type 

   The link type indicates the OTUk/HO ODUk type of the TE link.  

   The TS bandwidth of different types of OTUk is different. The TS 
   bandwidth in an OTUk is inreaseing along with the increasing of k 
   (see [G709-V3]). The bandwidth of a TS in a TE link can be deduced 
   from the TS type and link type of the TE link. For example, the 
   bandwidth of a 1.25G TS without NJO (Negative Justification 
   Opportunity) in an OTU2 is about 1.249409620 Gbps, while the 
   bandwidth of a 1.25G TS without NJO in an OTU3 is about 1.254703729 
   Gbps.  

   The actual TS bandwidth of a TE link is useful to determine the TS 
   number needed by an ODUflex service. And the actual TS bandwidth of a 
   TE link can be deduced by the TE link type and TS type.  

   In the case of link bundling, only the component links with the same 
   TS type and TE link type can be bundled together. 

4.3. LO ODU signal type 

   It is possible that some equipment can not always support all the LO 
   ODU signal types. When a path computation procedure for a LO ODU is 
   performed, it needs to check whether a link has the capability to 
   carry a specific type of LO ODU or not. If a link can not carry this 
   type of LO ODU, it should be excluded during the path computation. 
   Only the links with the capability of carrying this type of LO ODU 
   can be the candidates. 

   For example, in the following figure, the interfaces IF1, IF2, IF8, 
   IF7, IF5 and IF6 can support ODUflex signals, while the interfaces 
   IF3 and IF4 can not support ODUflex signals. In this case, if one 
   ODUflex connection from A to C is requested, link #1 and #2 are 
   excluded, link #3 and link #4 are the candidates (the possible path 
   could be A-D-C through link #3 and link #4).    

    

    

    

 
 
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                              +-----+ 
                    link #3   |     |  link #4 
            +-----------------+  D  +-----------------+ 
            |              IF8|     |IF7              | 
            |                 +-----+                 | 
            |                                         | 
            |IF1                                   IF6| 
         +--+--+              +-----+              +--+--+ 
         |     |    link #1   |     |    link #2   |     | 
         |  A  +--------------+  B  +--------------+  C  | 
         |     |IF2        IF3|     |IF4        IF5|     | 
         +-----+              +-----+              +-----+ 

   Therefore, it is necessary to advertise the LO ODU types that the OTU 
   or HO ODU TE link can support. 

4.4. TE link Total Bandwidth 

   For an unbundled link, the Total Bandwidth is dependent on the type 
   of the OTU or HO ODU, while in case of link bundling, the Total 
   Bandwidth is the sum of the total bandwidth of all the physical links 
   composing the TE link. 

   For a specific OTUk or HO ODUk TE link, the Total Bandwidth can be 
   deduced through the total number of the Tributary Slots. For example, 
   an unbundled OTU4 link has 80 Tributary Slots with 1.25Gbps. If two 
   component OTU4 links are bundled, the TE link has 160 Tributary Slots 
   with 1.25Gbps. 

4.5. TE link Unreserved Bandwidth 

   In the GMPLS based OTN networks, the Unreserved Bandwidth of a TE 
   link is the sum of the unreserved bandwidths of all the component 
   links associated with the bundled link. 

   The unreserved bandwidth can be accounted through the unallocated 
   Tributary Slots of the TE link. 

4.6. Maximum LSP Bandwidth 

   The Maximum Bandwidth that a LSP can occupy in a TE link is 
   determined by the component link with the maximum unreserved 
   bandwidth in this TE link.  

   For example, if two OTU3 component links are bundled to a TE link, 
   the unreserved bandwidth of the first component link is 20*1.25G TSs, 
   and the unreserved bandwidth of the second component link is 24*1.25G 
 
 
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   TSs. Then the unreserved bandwidth of this TE link is 44*1.25G TSs, 
   but the maximum TSs that a LSP can occupy in this TE link is 24, not 
   44. 

5. OSPF extensions 

   In terms of GMPLS based OTN networks, each OTUk/HO ODUk can be viewed 
   as a component link, and each component link can carry one or more 
   types of LO ODU. One or more component links with the same attributes 
   can be bundled as a TE link (see [RFC 4201] for link bundling).  

   Each TE LSA can carry a top-level TLV with several nested sub-TLVs to 
   describe different attributes of a TE link. Two top-level TLVs are 
   defined in [RFC 3630]. (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] and [RFC 4203]. 

   A general Interface Switching Capability Descriptor (ISCD) sub-TLV is 
   defined In [RFC 4203]. The bandwidth accounting is encoded in a 4 
   octets field in the IEEE floating point format. Max LSP Bandwidth is 
   accounted at each priority X (0~7).  

   To keep the minor changes on the existing routing protocol, the 
   routing procedures and the TLVs defined in the existing standard 
   documents, such as [RFC 3630] and [RFC 4203] should be reused as 
   possible.  

   Therefore, OTN specific routing information can be simply carried in 
   the "Switching Capability-specific information" of ISCD defined in 
   [RFC 4203].   

   The routing procedures are the same as [RFC 3630] and [RFC 4203]. 

5.1. Extensions to Interface Switching Capability Descriptor 

   The Interface Switching Capability Descriptor is defined 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 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   | Switching Cap |   Encoding    |           Reserved            | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                  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              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |        Switching Capability-specific information              | 
   |                  (variable)                                   | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   A new type of Switching Cap is introduced to distinguish the 
   evolutive OTN and the existing TDM networks (e.g., SDH networks). The 
   new Switching Cap type is defined in the following: 

    110   Evolved OTN (Digital Wrapper layer of G.709) 
    

   When the Switching Capability field is evolved OTN, the Max LSP 
   Bandwidth at priority x is counted by TS number.  

   When the Switching Capability field is evolved OTN, the Switching 
   Capability specific information field includes OTN Specific 
   Information, which shows in the following: 

    

    
 
 
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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 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     |Res| T |OD(T)Uk|   Reserved    |   Signal Flags  |G|F|E|D|C|B|A| 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
     | Resv. |       Total TS        | Resv. |     Unreserved TS     | 
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    

   The type of this sub-TLV is TBD. The length of this TLV is eight 
   octets.  

   o  T bits (2 bits): Indicates the type of the Tributary Slot of this 
      TE link, value 0 means the TS type is 1.25Gbps, value 1 means the 
      TS type is 2.5Gbps.  

   o  OD(T)Uk (4 bits): Indicates the type of the TE link, i.e. the 
      server layer signal that the LO ODUs can be mapped or multiplexed 
      into. The following values are defined:  

        0: Reserved (for future use) 

        1: OTU1/HO ODU1 

        2: OTU2/HO ODU2 

        3: OTU3/HO ODU3 

        4: OTU4/HO ODU4 

        5: OTU2e/HO ODU2e 

        6: HO ODU3e1 

        7: HO ODU3e2 

        8-15: Reserved (for future use) 

   Note that an ODU3e1/ODU3e2 must carry several LO ODUs, non-OTN 
   signals can not be mapped into ODU3e1/ODU3e2 directly. So 
   ODU3e1/ODU3e2 can not be a LO ODU, and OTU3e1/OTU3e2 can not be a 
   server layer for LO ODU.  

   The bandwidth of a TS in this TE link can be deduced from T bit and 
   OD(T)Uk field.  
 
 
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   o  Signal Flags (16 bits): This field indicates the LO ODU type 
      supported by the TE link. A flag set to 1 indicates that the TE 
      link supports the corresponding LO ODU signal. Currently the 
      following flags are defined:  

        Flag A: indicates whether LO ODU0 is supported. 

        Flag B: indicates whether LO ODU1 is supported. 

        Flag C: indicates whether LO ODU2 is supported. 

        Flag D: indicates whether LO ODU3 is supported. 

        Flag E: indicates whether LO ODU4 is supported. 

        Flag F: indicates whether LO ODU2e is supported. 

        Flag G: indicates whether LO ODUflex is supported. 

      Other bits are reserved and must be set to zero when sent and 
      should be ignored when received.  

   o  Total TS (12 bits): Indicates the total TS number of the TE link.   

   o  Unreserved TS (12 bits): Indicates the number unreserved TS in the 
      TE link. 

   When a node receives a LSA with Switching Capability type 110, the 
   Maximum Bandwidth sub-TLV and Unreserved Bandwidth sub-TLV in this 
   LSA SHOULD be ignored if they exist, the bandwidth information MUST 
   be deduced from ISCD sub-TLV (i.e., Total TS, Unreserved TS). 

   All the reserved fields must be set to zero and should be ignored 
   when received. 

6. Compatibility Considerations 

   The legacy nodes that do not implement the extensions defined in this 
   document are able to ignore the LSA containing an ISCD sub-TLV with 
   the Switching Cap type 110, because it is an unknown value. They will 
   continue to flood the LSA to other neighbors, but will not use the 
   information carried in this LSA.  

7. Example 

   Based on the sub-TLVs defined in [RFC 3630], [RFC 4203] and this 
   document, a G.709 digital TE link can be described as follows. 
 
 
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                   +------+ component link 1 +------+ 
                   |      +------------------+      | 
                   |  N1  +------------------+  N2  | 
                   |      | component link 2 |      | 
                   +--+---+                  +---+--+ 
    

   This picture shows a simple example of an OTN network. Both the link 
   type of the two component links are OTU3 and both of the two 
   component links have the capability of carrying ODU0, ODU1, ODU2 and 
   ODUflex client signals. The TS type is 1.25Gbps, the number of the 
   total Tributary Slots is 32.  

   The two component links have the same nature, so the two component 
   links can be bundled as a TE link. It is also feasible that each 
   component link can be regarded as a TE link separately.  

   If the two component links are bundled together, N1 and N2 should 
   assign a link local ID to the TE link. Then N1 can get the link 
   remote ID automatically or manually.  

   N1 can generate an LSA to describe the above attributes of the TE 
   link. Suppose the link IDs are unnumbered, the LSA should carry a 
   link TLV with the following nested minimal sub-TLVs: 

   < G.709 Digital Link > ::=  < Link Type > < Link ID > < Link 
   Local/Remote Identifiers > < Interface Switching Capability 
   Descriptor > 

   o  Link Type sub-TLV: Defined in [RFC 3630], G.709 digital links are 
      always type 1 - Point-to-point link. 

   o  Link ID sub-TLV: Defined in [RFC 3630], for point-to-point link, 
      indicates the remote router ID. 

   o  Link Local/Remote Identifiers sub-TLV: Defined in [RFC 4203], 
      indicates the local link ID and the remote link ID. 

   o  Interface Switching Capability Descriptor sub-TLV: Defined in this 
      document, carries the characteristic of this G.709 digital TE 
      link. 

   Suppose the unreserved TS number of component link 1 is 20, and the 
   unreserved TS number of component link 2 is 28. Also Suppose the Max 
   LSP Bandwidth at priority 0 of component link 1 is 10 TSs, and the 
   Max LSP Bandwidth at priority 0 of component link 2 is 18 TSs.  
 
 
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   The ISCD sub-TLV in this LSA will carry the above attributes, i.e. 
   the value of T bits is 1, OD(T)Uk bits is 3, total TS field is 64, 
   Unreserved TS field is 48, Max LSP Bandwidth at priority 0 field is 
   18 TSs, and A/B/C/G bits are set to indicate the types of LO ODU that 
   this TE link can carry. 

   When another node receives this LSA, it can determine that this TE 
   link can carry ODU0, ODU1, ODU2, ODUflex signals. The TS type is 
   1.25G, and the real bandwidth of TS is about 1.254703729 Gbps.  

   An ODUflex signal at priority 0 can occupy 18 TS at most in this TE 
   link. If an ODU0 (priority 0) path computation is performed, this TE 
   link is a candidate. If a 40G ODUflex (priority 0) path computation 
   is performed, this TE link should be excluded, because this ODUflex 
   signal needs more than 18 TSs. 

8. Security Considerations 

   TBD. 

9. IANA Considerations 

   TBD. 

10. Acknowledgments 

   TBD. 

11. References 

11.1. Normative References 

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

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

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

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



 
 
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   [WSON-Frame] G. Bernstein, Y. Lee, W. Imajuku, "Framework for GMPLS        
                and PCE Control of Wavelength Switched Optical                 
                Networks", work in progress: draft-ietf-ccamp-rwa-WSON-            
                Framework-02.txt, March 2009. 

   [WSON-OSPF] Fatai Zhang, Y. Lee, etc., " OSPF Extensions in Support 
               of Routing and Wavelength Assignment (RWA) in Wavelength 
               Switched Optical Networks (WSONs) ", work in progress: 
               draft-zhang-ccamp-rwa-wson-routing-ospf-01.txt, July 2009. 

11.2. Informative References 

   [Gsup43]  ITU-T, "Proposed revision of G.sup43 (for agreement)", 
             December 2008. 

   [G709]    ITU-T G.709 Recommendation, Interface for the Optical 
             Transport Network (OTN) ITU-T, March 2003.  

   [G709-v3] ITU-T, "Draft revised G.709, version 3", consented by ITU-T 
             on Oct 2009. 

12. Authors' Addresses 

   Daniele Ceccarelli
   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


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   Bantian, Longgang District
   Shenzhen 518129 P.R.China
   Phone: +86-755-28972912
   Email: zhangfatai@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: +86-755-28972910
   Email: danli@huawei.com

13. Contributors 

   Xiaobing Zi
   Huawei Technologies
   F3-5-B R&D Center, Huawei Base
   Bantian, Longgang District
   Shenzhen 518129 P.R.China
   Phone: +86-755-28973229
   Email: zixiaobing@huawei.com


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