Internet DRAFT - draft-zhang-ccamp-gmpls-h-lsp-mln

draft-zhang-ccamp-gmpls-h-lsp-mln



Network Working Group                                        Fatai Zhang 
Internet Draft                                                Xian Zhang 
Category: Standards Track                                         Huawei        
                                                     O. Gonzalez de Dios 
                                   Telefonica Investigacion y Desarrollo 
                                                          C. Margaria. C 
                                                                 Coriant
Expires: January 10, 2014                                  July 11, 2013 
                                    
                                    
                   GMPLS-based Hierarchy LSP Creation 
                in Multi-Region and Multi-Layer Networks 
                                    
                 draft-zhang-ccamp-gmpls-h-lsp-mln-05.txt 


Abstract 
 
   This specification describes the hierarchical LSP creation models in 
   the Multi-Region and Multi-Layer Networks (MRN/MLN), and provides the 
   extensions to the existing protocol mechanisms described in [RFC4206], 
   [RFC6107] and [RFC6001] to create a hierarchical LSP in multiple 
   layer networks. 

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   
   Task Force (IETF), its areas, and its working groups.  Note that   
   other groups may also distribute working documents as Internet-   
   Drafts. 

   Internet-Drafts are draft documents valid for a maximum of six months   
   and may be updated, replaced, or obsoleted by other documents at any   
   time.  It is inappropriate to use Internet-Drafts as reference   
   material or to cite them other than as "work in progress." 

   The list of current Internet-Drafts can be accessed at   
   http://www.ietf.org/ietf/1id-abstracts.txt. 

   The list of Internet-Draft Shadow Directories can be accessed at   
   http://www.ietf.org/shadow.html. 

   This Internet-Draft will expire on January 10, 2014. 

    

 
 
 
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Table of Contents 

    
   1. Introduction ................................................ 2 
      1.1. Conventions used in this document .......................3 
   2. Provisioning of FA-LSP in Server Layer Network ...............3 
      2.1. Selection of Switching Layers........................... 3 
      2.2. Selection of Switching Granularity Levels ...............4 
      2.3. Selection of Adaptation Capabilities ....................6 
   3. Signaling Requirements for Server Layer Selection ............7 
      3.1. Model 1: Pre-provisioning of FA-LSP .....................8 
      3.2. Model 2: Signaling triggered server layer path computation 
      and setup ................................................... 9 
      3.3. Model 3: Signaling triggered server layer path, with explicit 
      server path ................................................. 9 
   4. Signaling Extensions ERO Sub-Object .........................10 
      4.1. SERVER_LAYER_INFO ERO Subobject ........................10 
      4.2. Processing of SERVER_LAYER_INFO sub-object .............12 
      4.3. Alternative Encoding Solutions .........................12 
   5. Security Considerations..................................... 13 
   6. IANA Considerations ........................................ 13 
   7. Acknowledgments ............................................ 13 
   8. References ................................................. 13 
      8.1. Normative References................................... 13 
      8.2. Informative Reference.................................. 14 
   9. Authors' Addresses ......................................... 15 
 
1. Introduction 

   Networks may comprise multiple layers which have different switching 
   technologies or different switching granularity levels. The GMPLS 
   technology is required to support control of such network. 

   [RFC5212] defines the concept of MRN/MLN and describes the framework 
   and requirements of GMPLS controlled MRN/MLN. The GMPLS extension for 
   MRN/MLN, including routing and signaling aspects, is described in 
   [RFC6001]. 

   [RFC4206] and [RFC6107] describe how to set up a hierarchical LSP 
   passing through multi-layer networks and how to advertise the 
   forwarding adjacency LSP (FA-LSP) created in the server layer network 
   as a TE link via GMPLS signaling and routing protocols.  

   Based on these existing standards, this document further describes 
   the provisioning of a FA-LSP when the region-edge nodes support 
 
 
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   multiple interface switching capabilities and/or multiple switching 
   granularities and/or adaptation functions, and then provides the 
   extensions to the RSVP-TE protocol in order to set up a hierarchical 
   LSP according to the modes of hierarchical LSP provisioning. 

1.1. 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]. 

2. Provisioning of FA-LSP in Server Layer Network 

2.1. Selection of Switching Layers 

   As described in [RFC5212], the edge node of a region always has 
   multiple Interface Switching Capabilities (ISCs), i.e., it contains 
   multiple matrices which may be connected to each other by internal 
   links. Nodes with multiple ISCs are further classified as "simplex" 
   or "hybrid" nodes by [RFC5212] and [RFC5339], where the simplex node 
   advertises several TE links each with a single ISC value carried in 
   its ISCD sub-TLV, while the hybrid node advertises a single TE link 
   containing more than one ISCD each with a different ISC value. An 
   example of a hybrid node with a link having multiple ISCs is shown in 
   Figure 1, copied from [RFC5339].  

                                  Network element 
                           ............................. 
                           :            --------       : 
                           :           |  PSC   |      : 
                           :           |        |      : 
                           :         --|#a      |      : 
                           :        |  |   #b   |      : 
                           :        |   --------       : 
                           :        |       |          : 
                           :        |  ----------      : 
                           :    /|  | |    #c    |     : 
                           :   | |--  |          |     : 
                 Link1 ========| |    |    TDM   |     : 
                           :   | |----|#d        |     : 
                           :    \|     ----------      : 
                           :............................ 

              Figure 1 - Hybrid node (Copied from [RFC5339]) 

   In the case where a edge node of a region is a hybrid node, selection 
   of which server layer to create the FA-LSP is necessary. 
 
 
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   Figure 2 shows an multi-layer network, where node B and C are region 
   edge nodes having three switching matrices which support, for 
   instance, PSC, TDM and WDM switching, respectively. The three 
   switching matrices are connected to each other by the internal links. 
   Both the link between B and E and the link between E and C support 
   TDM and WDM switching capabilities. 

   +-------+  +------------+                   +------------+  +-------+ 
   | +---+ |  |   +---+    |        FA         |    +---+   |  | +---+ | 
   | |PSC+-+--+---+PSC|....|...................|....|PSC+---+--+-+PSC| | 
   | +---+ |  | +-+-+-+    |                   |    +-+-+-+ |  | +---+ | 
   +-------+  | |   |      |                   |      |   | |  +-------+ 
    Node A    | |   |      |  +-------------+  |      |   | |   Node D 
              | | +-+-+    |  |    +---+    |  |    +-+-+ | | 
              | | |TDM|+   |  |   +|TDM|+   |  |   +|TDM| | | 
              | | +-+-+|   |  |   |+-+-+|   |  |   |+-+-+ | | 
              | |   |  ||\ |  | /||  |  ||\ |  | /||  |   | | 
              | |   |  +| ||  || |+  |  +| ||  || |+  |   | | 
              | +-+-+-+ | |====| | +-+-+ | |====| | +-+-+-+ | 
              |   |WDM|-| ||  || |-|WDM|-| ||  || |-|WDM|   | 
              |   +---+ |/ |  | \| +---+ |/ |  | \| +---+   | 
              +------------+  +-------------+  +------------+ 
                Node B            Node E            Node C  

              Figure 2 - MLN with multiple ISCs at edge node 

   As can be seen in Figure 2, there are two choices when providing FA 
   in the PSC layer network between node B and C: one is creating a FA-
   LSP with TDM switching matrix through node B, E and C, the other is 
   creating a FA-LSP with WDM switching matrix through node B, E and C. 

   [RFC6001] introduces a new SC (Switching Capability) sub-object into 
   the XRO (ref. to [RFC4874]). This sub-object is used to indicate 
   which switching capability is not expected to be used. When one of 
   the switching capabilities is selected, the SC sub-object can be 
   included in the message to exclude all other SCs. 

2.2. Selection of Switching Granularity Levels 

   Even in the case where the edge node only has one switching 
   capability in the server layer, there may be still multiple choices 
   for the server layer network to set up a FA-LSP to provide new FA in 
   the client layer network. This is because the server layer network 
   may have the capability of providing different switching granularity 
   levels for the FA-LSP. 

    
 
 
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   +-------+   +---------+                       +---------+   +-------+ 
   | +---+ |   |  +---+  |           FA          |  +---+  |   | +---+ | 
   | |PSC|-+---+--+PSC|..|.......................|..|PSC+--+---+-|PSC| | 
   | +---+ |   |  +-+-+  |                       |  +-+-+  |   | +---+ | 
   +-------+   |    |    | ODU1/           ODU1/ |    |    |   +-------+ 
    Node A     |    |    | ODU2/ +-------+ ODU2/ |    |    |    Node D 
               |  +-+-+  | ODU3  | +---+ | ODU3  |  +-+-+  | 
               |  |TDM+--+-------+-+TDM+-+-------+--+TDM|  | 
               |  +---+  |       | +---+ |       |  +---+  | 
               +---------+       +-------+       +---------+ 
                 Node B           Node E           Node C 

        Figure 3a - Multiple switching granularities in server layer 

   Figure 3a shows an example multi-region network, where the edge node 
   B and C have PSC and TDM switching matrices, and where the TDM 
   switching matrix supports ODU1, ODU2 and ODU3 switching levels. 
   Therefore, when an FA between node B and C in the PSC layer network 
   is needed, either of ODU1, ODU2 or ODU3 connection (FA-LSP) can be 
   created in the TDM layer network. 

    

    |<----------------------- ODU0 Connection ----------------------->| 
    |                                                                 | 
   ++------+   +---------+                       +---------+   +------++ 
   | +---+ |   |  +---+  |      FA (ODU1/2/3)    |  +---+  |   | +---+ | 
   | |TDM|-+---+--+   |..|.......................|..|   +--+---+-|TDM| | 
   | +---+ |   |  |   |  |                       |  |   |  |   | +---+ | 
   +-------+   |  |TDM|  |       +-------+       |  |TDM|  |   +-------+ 
    Node A     |  |   |  | OTU3  | +---+ | OTU3  |  |   |  |    Node D 
               |  |   +--+-------+-+TDM+-+-------+--+   |  | 
               |  +---+  |       | +---+ |       |  +---+  | 
               ++--------+       +-------+       +--------++ 
                |Node B           Node E           Node C | 
                |                                         | 
                |<--------- FA LSP (ODU1/2/3)------------>| 

                  Figure 3b - TDM nested LSP provisioning 

    

   Figure 3b is another example multi-layer network within the same 
   region. When there is a need to set up an FA between node B and C for 
   the client layer ODU0 connection, the server layer has multiple 
 
 
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   choices, e.g., ODU1 or ODU2 or ODU3, for the FA-LSP if the multi-
   stage multiplexing is supported at node B and C. 

    |<---------------- Client layer LSP (Bandwidth 1) --------------->| 
    |                                                                 | 
   ++------+   +---------+                       +---------+   +------++ 
   | +---+ |   |  +---+  |           FA          |  +---+  |   | +---+ | 
   | |PSC|-+---+--+   |..|.......................|..|   +--+---+-|PSC| | 
   | +---+ |   |  |   |  |                       |  |   |  |   | +---+ | 
   +-------+   |  |PSC|  |       +-------+       |  |PSC|  |   +-------+ 
    Node A     |  |   |  |       | +---+ |       |  |   |  |    Node D 
               |  |   +--+-------+-+PSC+-+-------+--+   |  | 
               |  +---+  |       | +---+ |       |  +---+  | 
               ++--------+       +-------+       +--------++ 
                |Node B           Node E           Node C | 
                |                                         | 
                |<--- Service layer LSP (Bandwidth 2) --->|                     

                  Figure 3c - PSC nested LSP provisioning 

   Figure 3c is a third example showing an LSP nesting scenario in a PSC 
   signal-layer network (e.g., an MPLS-TP network). A PSC tunnel passing 
   through node B, E and C is requested to carry the client layer LSP. 
   There are multiple choices of the bandwidth of the tunnel, on the 
   premise that the bandwidth of the FA-LSP is equal to or larger than 
   the client layer LSP. 

   The selection of server layer switching matrix and switching 
   granularity is based on both policy and bandwidth resources. The 
   selection can be performed by a planning tool and/or NMS/PCE/VNTM 
   (Virtual Network Topology Manager, see [RFC5623]) and/or the network 
   node. 

    

2.3. Selection of Adaptation Capabilities 

   Adaptation function also needs to be selected when creating the 
   server layer connection. This is because the edge nodes may support 
   multiple adaptation functions. 

    

    

    

 
 
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   +-------+   +-----------+                     +---------+   +-------+ 
   | +---+ |   |   +---+   |          FA         |  +---+  |   | +---+ | 
   | |PSC|-+---+---+PSC|...|.....................|..|PSC+--+---+-|PSC| | 
   | +---+ |   |   +---+   |                     |  +-+-+  |   | +---+ | 
   +-------+   |___|_ _|___|                     |  __|__  |   +-------+ 
    Node A     |\_A_/ \_B_/|                     |  \_A_/  |    Node D 
               |   |   |   |      +-------+      |    |    | 
               |   +---+   |      | +---+ |      |  +-+-+  | 
               |   |TDM+---+------+-+TDM+-+------+--+TDM|  | 
               |   +---+   |      | +---+ |      |  +---+  | 
               +-----------+      +-------+      +---------+ 
                  Node B           Node E          Node C 

      _____                             _____ 
      \_A_/: Adaptation_Function_A;     \_B_/: Adaptation_Function_B;  

                Figure 4 - Selection of adaptation function 

   For example, in Figure 4, edge node B supports two adaptation 
   functions, i.e., adaptation_function_A and adaptation_function_B, 
   while edge node C only supports adaptation_function_A. In this case, 
   only adaptation_function_A can be used for the server layer 
   connection. 

   The Call procedure ([RFC4974]) may be used between edge node B and C 
   to negotiate and determine the adaptation function for the server 
   layer if the Call function is supported. 

3. Signaling Requirements for Server Layer Selection 

   [RFC5623], the framework of PCE-based MLN, provides the models of 
   cross-layer LSP path computation and creation, which are listed below: 

   - Inter-Layer Path Computation Models: 

      o Single PCE 

      o Multiple PCE with inter-PCE 

      o Multiple PCE without inter-PCE 

   - Inter-Layer Path Control Models: 

      o PCE-VNTM cooperation 

 
 
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      o Higher-layer signaling trigger 

      o NMS-VNTM cooperation (integrated flavor) 

      o NMS-VNTM cooperation (separate flavor)   

   This section keeps alignment with [RFC5623] except that the 
   restriction of using a PCE for path computation is not necessary 
   (i.e., other element, such as a network node, may also have path 
   computation capability). 

   In this document, those models in [RFC4206] are mapped  into 3 models 
   on the viewpoint of signaling: 

   - Model 1: Pre-provisioning of FA-LSP 

   - Model 2: Signaling triggered server layer path computation and 
      setup 

   - Model 3: Signaling triggered server layer path, with explicit 
      server path.  

    

3.1. Model 1: Pre-provisioning of FA-LSP 

   In this model, the FA-LSP in the server layer is created before 
   initiating the signaling of the client layer LSP. Two typical 
   scenarios using this model are: 

   - Network planning and building at the stage of client network 
      initialization. 

   - NMS/VNTM triggering the creation of FA-LSP when computing the path 
      of client layer LSP. The path control models of PCE-VNTM 
      cooperation and NMS-VNTM cooperation (both integrated and separate 
      flavor) in [RFC5623] belong to this scenario. 

   In such case, the server layer selection and path computation is 
   performed by planning tool or NMS/PCE/VNTM or the edge node. The 
   signaling of client layer LSP and server layer FA-LSP are separated. 
   The normal LSP creation procedures ([RFC3471] and [RFC3473]) are 
   followed to set up these two LSPs and no new extension is required. 

    


 
 
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3.2. Model 2: Signaling triggered server layer path computation and 
   setup 

   In this model, the source node of client layer LSP only computes the 
   route within its own layer network. When the signaling of the client 
   layer LSP reaches at the region edge node, the edge node performs 
   server layer FA-LSP path computation and then creates the FA-LSP. 
   When a PCE is introduced to perform path computation in each layer of 
   the multi-layer network, this model is the same as the model of 
   "higher-layer signaling trigger with Multiple PCE without inter-PCE" 
   in [RFC5623]. 

   In such case, the edge node will receive the client layer PATH 
   message with a loose ERO indicating an FA is requested, and may 
   perform the server layer selection (e.g., through the server layer 
   PCE or the VNTM) and then compute and set up the FA-LSP. The 
   signaling procedure of client layer LSP and server layer FA-LSP is 
   described in detail in [RFC4206] and [RFC6107]. 

   It's possible that the source node of the client layer LSP selects 
   the server layer SC and/or granularity and/or adaptation function 
   when performing path computation in the client layer, and requests or 
   suggests the edge node to use an appointed server layer to create the 
   FA-LSP.  

   In this case, the XRO including SC sub-object ([RFC6001]) is adopted 
   for the server layer SC exclusion, which can be used indirectly to 
   select server layer SC. Such solution is not straightforward enough. 
   Furthermore it cannot be used for the selection of server layer 
   granularity and adaptation function. Therefore, new extensions for 
   the selection of server layer SC, switching granularity and 
   adaptation function are required. 

    

3.3. Model 3: Signaling triggered server layer path, with explicit 
   server path 

   In this model, the source node of the client layer LSP performs a 
   full path computation including the client layer and the server layer 
   routes. The server layer FA-LSP creation is triggered at the edge 
   node by the client layer LSP signaling. When a PCE is introduced to 
   perform path computation in the multi-layer network, this model is 
   the same as the model of "Higher-layer signaling trigger with Single 
   PCE" or "Higher-layer signaling trigger with Multiple PCE with inter-
   PCE" in [RFC5623]. 

 
 
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   In such case, the server layer selection and server layer path 
   computation is performed at the source node of the client layer LSP 
   (e.g., through VNTM or PCE), but not at the edge node.  

   In [RFC4206], the ERO which contains the list of nodes and links 
   (including the client layer and server layer) along the path is used 
   in the client layer PATH message. The edge node can find out the tail 
   end of the FA-LSP based on the switching capability of the node using 
   the IGP database (see session 6.2 of [RFC 4206]). 

   Similar to the problem of model 2, the edge node is not aware of 
   which switching granularity and which adaptation function to be 
   selected for the FA-LSP because the ERO and/or XRO do not contain 
   such information. Therefore, the edge node may not be able to create 
   the FA-LSP, or may select another switching granularity by itself 
   which is different from the one selected previously at the source 
   node, which makes the creation of hierarchy LSP out of control.  

   Therefore, new extensions for the selection of server layer SC, 
   switching granularity and adaptation function are also required in 
   this model. 

    

4. Signaling Extensions ERO Sub-Object 

4.1. SERVER_LAYER_INFO ERO Subobject 

   In order to solve the problems described in the previous sections, a 
   new sub-object named SERVER_LAYER_INFO sub-object is introduced in 
   this document, which is carried in the ERO and is used to explicitly 
   indicate which server layer to create the FA-LSP.  

   The SERVER_LAYER_INFO sub-object is put immediately after the node or 
   link (interface) address sub-object, indicating the related node is a 
   region edge node on the LSP in the ERO.  

   The format of the SERVER_LAYER_INFO sub-object is shown below: 

    

    

    

    

 
 
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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 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |L|    Type     |     Length    |M|         Reserved            | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   | LSP Enc. Type |Switching Type |            G-PID              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Traffic Spec Length         | TSpec Type    | Reserved      |  
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                     Traffic Parameters                        | 
   ~                                                               ~ 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 

   [Editor's note: the encoding is still under discussion.] 

   - L bit: MUST be zero and MUST be ignored when received. 

   - Type: The SERVER_LAYER_INFO sub-object has a type of xx (TBD). 

   - Length: The total length of the sub-object in bytes, including the 
      Type and Length fields. The value of this field is always a 
      multiple of 4. 

   - M (Mandatory) bit: When set, it means the edge node MUST set up 
      the FA-LSP in the appointed server layer; otherwise, the appointed 
      server layer is suggested and the edge node may select other 
      server layer by local policy. 

   - LSP Encoding Type, Switching Type and G-PID: These 3 fields are 
      used to point out which switching layer is requested to set up the 
      FA-LSP. The values of these 3 fields are inherited from the 
      Generalized Label Request Object in GMPLS signaling, referring to 
      [RFC3471], [RFC3473] and other related standards and drafts. Note 
      that G-PID can be used to indicate the payload type of the server 
      layer (i.e., the client signal) as well as the adaptation function 
      for adapting the client signal into the server layer FA-LSP. 

   - Traffic Spec Length, TSpec Type, Traffic Parameters: The traffic 
      parameters field is used to indicate the switching granularity of 
      the FA-LSP. The format of this field depends on the TSpec Type 
      Traffic Spec Length  and is consistent with the existing standards 
      and drafts. For example, the traffic parameters of Ethernet, 
      SONET/SDH and OTN are defined in [RFC6003], [RFC4606] and [OTN-
      ctrl] respectively.  

    

 
 
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4.2. Processing of SERVER_LAYER_INFO sub-object 

   As described in RFC3209 and RFC3473 the ERO is managed as a sub-
   object list. The SERVER_LAYER_INFO sub-object MUST be appended after 
   the existing sub-object defined in [RFC3209], [RFC3473], [RFC3477], 
   [RFC4873], [RFC4874], [RFC5520] and [RFC5553] TBD:extensions.  

   When a node receives a PATH message containing ERO and finds that 
   there is a SERVER_LAYER_INFO sub-object immediately after the node or 
   link address sub-object related to itself, the node determines that 
   it's a region edge node. Then, the edge node finds out the server 
   layer selection information from the sub-object: 

   - Determine the switching layer by the LSP Encoding Type and 
      Switching Type fields; 

   - Determine the switching granularity of the FA-LSP by the Traffic 
      Parameters field; 

   - Determine the adaptation function for adapting the client signal 
      into the server layer FA-LSP by the G-PID field. 

   The edge node MUST then determine the other edge of the region, i.e., 
   the tail end of the FA-LSP, with respect to the subsequence of hops 
   of the ERO. The node that satisfies the following conditions will be 
   treated as the tail end of the FA-LSP: 

   - There is a SERVER_LAYER_INFO sub-object that immediately follows 
      the node or link address sub-object which is related to that node; 

   - The LSP Encoding Type, Switching Type, G-PID and the Traffic 
      Parameters fields of this SERVER_LAYER_INFO sub-object is the same 
      as the SERVER_LAYER_INFO sub-object corresponding to the head end; 

   - The node is the first one that satisfies the two conditions above 
      in the subsequence of hops of the ERO. 

   If a match of tail end is found, the head end now has the clear 
   server layer information of the FA-LSP and then initiates an RSVP-TE 
   session to create the FA-LSP in the appointed server layer between 
   the head end and the tail end.  

4.3. Alternative Encoding Solutions 

   [Editor's note: the section is still under discussion.] 


 
 
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   A first alternative solution is to use the mechanism defined in [LSP-
   RO], i.e., create an ERO HOP attribute TLV.  

   The content and procedure are not changed from the previous section. 

5. A second alternative solution aims to simplify the SERVER_LAYER_INFO 
   processing by using the SERO mechanisms. This can be a new 
   requirements to the SERO or to the ERO Hop attribute. This 
   alternative is not further described here but mentioned for 
   discussions. 

6. Security Considerations 

   TBD. 

7. IANA Considerations 

   TBD. 

8. Acknowledgments 

   TBD. 

    

9. References 

9.1. Normative References 

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

   [RFC3945]   Mannie, E., "Generalized Multi-Protocol Label Switching 
               (GMPLS) Architecture", RFC 3945, October 2004. 

   [RFC3209]   D. Awduche et al, "RSVP-TE: Extensions to RSVP for LSP 
               Tunnels", RFC3209, December 2001. 

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

   [RFC3473]   L. Berger, Ed., "Generalized Multi-Protocol Label 
               Switching (GMPLS) Signaling Resource ReserVation 
               Protocol-Traffic Engineering (RSVP-TE) Extensions", RFC 
               3473, January 2003. 

 
 
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   [RFC5212]   K. Shiomoto et al, "Requirements for GMPLS-Based Multi-
               Region and Multi-Layer Networks (MRN/MLN)", RFC5212, July 
               2008. 

   [RFC5339]   JL. Le Roux et al, "Evaluation of Existing GMPLS 
               Protocols against Multi-Layer and Multi-Region Networks 
               (MLN/MRN)", RFC5339, September 2008. 

   [RFC4206]   K. Kompella et al, "Label Switched Paths (LSP) Hierarchy 
               with Generalized Multi-Protocol Label Switching (GMPLS) 
               Traffic Engineering (TE)", RFC4206, October 2005. 

   [RFC6107]   K. Shiomoto, A. Farrel, "Procedures for Dynamically 
               Signaled Hierarchical Label Switched Paths", RFC6107, 
               February 2011. 

    [RFC6001]   Dimitri Papadimitriou et al, "Generalized Multi-Protocol 
               Label Switching (GMPLS) Protocol Extensions for Multi-
               Layer and Multi-Region Networks (MLN/MRN)", RFC6001, 
               October, 2010. 

9.2. Informative Reference 

   [RFC4974]   D. Papadimitriou and A. Farrel, "Generalized MPLS (GMPLS) 
               RSVP-TE Signaling Extensions in Support of Calls", 
               RFC4974, August 2007. 

   [RFC5623]   E. Oki et al, "Framework for PCE-Based Inter-Layer MPLS 
               and GMPLS Traffic Engineering", RFC 5623, September 2009. 

   [RFC4606]   E. Mannie, D. Papadimitriou, "Generalized Multi-Protocol 
               Label Switching (GMPLS) Extensions for Synchronous 
               Optical Network (SONET) and Synchronous Digital Hierarchy 
               (SDH) Control", RFC 4606, August 2006. 

   [OTN-ctrl]  Fatai Zhang et al, "Generalized Multi-Protocol Label 
               witching (GMPLS) Signaling Extensions for the evolving 
               G.709 Optical Transport Networks Control", draft-ietf-
               ccamp-gmpls-signaling-g709v3-08.txt, April, 2013. 

   [RFC6003]   D. Papadimitriou, "Ethernet Traffic Parameters", RFC6003, 
               October, 2010. 

   [LSP-RO]    Margaria, C., Giovanni, G., et al, "draft-ietf-ccamp-lsp-
               attribute-ro', draft-ietf-ccamp-lsp-attribute-ro-01.txt, 
               work I progress;  

 
 
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10. Authors' Addresses 

   Fatai Zhang 
   Huawei Technologies 
   F3-1B R&D Center, Huawei Base 
   Bantian, Longgang District 
   Shenzhen 518129 P.R.China 
    
   Phone: +86-755-28972603 
   Email: zhangfatai@huawei.com
    
    
   Xian Zhang 
   Huawei Technologies 
   F3-1B R&D Center, Huawei Base 
   Bantian, Longgang District 
   Shenzhen 518129 P.R.China 
    
   Phone: +86-755-28972645 
   Email: huawei.danli@huawei.com
    
    
   Yi Lin 
   Huawei Technologies Co., Ltd. 
   F3-1B R&D Center, Huawei Base 
   Bantian, Longgang District 
   Shenzhen 518129 P.R.China 
    
   Phone: +86-755-28972597 
   Email: yi.lin@huawei.com
    
    
    
   Oscar Gonzalez de Dios 
   Telefonica Investigacion y Desarrollo 
   Emilio Vargas 6 
   Madrid, 28045 Spain 
    
   Phone: +34 913374013 
   Email: ogondio@tid.es
    
    





 
 
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   Cyril Margaria 
   Coriant GmbH 
   St Martin Strasse 76 
   Munich,   81541 
   Germany 
    
   Phone: +49 89 5159 16934 
   Email: cyril.margaria@coriant.com
    
    
    
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