One document matched: draft-cui-netext-route-optimization-agent-ext-00.txt


Netext Working Group                                             X. Cui 
Internet Draft                                                   Huawei 
Intended status: Informational                         October 16, 2009 
Expires: April 2010 
                                   
 
                                      
             Reflector Extension for Route Optimization Agent 
           draft-cui-netext-route-optimization-agent-ext-00.txt 


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Abstract 

   Route Optimization is a very useful feature in Mobile IPv6. Mobile 
   node can communicate with correspondent node without the involvement 
   of the home agent by Route Optimization. But there are some 
   limitations to this feature. One problem is that the mobile node and 
   the correspondent node must be capable for Route Optimization. This 
   document introduces an extension mechanism used for Route 
   Optimization and this extension mechanism can enable Route 
   Optimization be used between mobile node and simple IP node. In the 
   extension solution, the MAG can reflect the RO-related signal 
   messages and fulfill the Route Optimization procedure on behalf of 
   the simple IP node. 

    

    

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]. 

    

    

    

    

    

    

    

    

    

    

    


 
 
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Table of Contents 

    
   1. Introduction....................................................4 
   2. Terminology.....................................................4 
   3. Scenario Analysis and Use Case..................................5 
      3.1. Issues if the CN can't support Route Optimization..........5 
      3.2. Motivation.................................................7 
      3.3. Requirement................................................9 
      3.4. Use Case for Agent Extension to Fulfill Route Optimization.9 
   4. Solution and Operation Consideration...........................12 
      4.1. MAG Operation.............................................12 
         4.1.1. Incoming Flow Transmission...........................13 
         4.1.2. Outgoing Flow Transmission...........................13 
         4.1.3. Conceptual Data Structures...........................14 
      4.2. Operation in Other Network Element........................15 
   5. Security Considerations........................................15 
   6. IANA Considerations............................................15 
   7. Acknowledgments................................................16 
   APPENDIX A: Future Extension and Use Case.........................17 
      A.1. Extension for Mobile Router in NEMO.......................17 
      A.2. Extension for IPv4/MIP4...................................18 
   8. References.....................................................18 
      8.1. Normative References......................................18 
      8.2. Informative References....................................18 
   Author's Addresses................................................18 
    
    

    

    

    

    

    

    

    

    

    

 
 
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1. Introduction 

   Mobile IPv6 protocol [RFC3775] provides a mobility extension to basic 
   IPv6 and introduces a Route Optimization (RO) mechanism. Route 
   Optimization enables mobile node (MN) to establish a directly 
   connection between mobile node and correspondent node (CN) without 
   the involvement of MN's home agent (HA).  

   But Route Optimization requires mobile node and correspondent node to 
   have some certain capabilities, such as MN's transmitting Home Test 
   Init (HoTI) message, Care-of Test Init (CoTI) message and direct 
   Binding Update message to CN, and CN's reflecting Home Test (HoT) 
   message, Care-of Test Init (CoT) message and Binding Ack message to 
   MN. 

   If the CN is a simple IP node without support for Route Optimization, 
   the MN with support for Route Optimization even can't use Route 
   Optimization with this CN, as [RFC3775] specified ''If a mobile node 
   attempts to set up route optimization with a node with only basic 
   IPv6 support, an ICMP error will signal that the node does not 
   support such optimizations and communications will flow through the 
   home agent.'' 

   From the MN's viewpoint, the IPv6 nodes with support for MIP and IPv6 
   nodes without support for MIP are using the unified address space, so 
   the MN can't distinguish whether a correspondent node is a RO-capable 
   node or a none-RO-capable node. When the network is composed of 
   mobile IPv6 nodes, IPv6 nodes with support for Route Optimization and 
   enormous quantity of simple IPv6 nodes with support for only basic 
   IPv6 protocol, lots of Route Optimization attempts will go to
   failure. 

   This document introduces an extension mechanism, which can be used 
   for IP nodes with only support for basic IPv6 protocol, to fulfill 
   the Route Optimization. 

    

2. Terminology 

   All the mobility related terms used in this document are to be 
   interpreted as defined in the Mobile IPv6 specification [RFC3775] and 
   Proxy Mobile IPv6 [RFC5213]. 

    
    

 
 
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3. Scenario Analysis and Use Case 

3.1. Issues if the CN can't support Route Optimization 

   Mobile IPv6 provides the Route Optimization mechanism, which may be 
   used between mobile nodes with support for MIPv6 or between mobile 
   nodes and IP nodes with support for Route Optimization. 

   In other situation, if the correspondent node can't support Route 
   Optimization, the correspondent node will reply an ICMP ERROR message 
   to the mobile node who initiates the Route Optimization. 

   On the other hand, Proxy Mobile IPv6 [RFC5213] provides a network-
   based mobility solution. In Proxy Mobile IPv6 domain, Mobile Access 
   Gateway (MAG) can provide a proxy mobility management functionality, 
   e.g. transmitting binding update message to mobility anchor on behalf 
   of the mobile node. 

   The MAG works as the mobility proxy for the mobile node, as [RFC5213] 
   defined, ''Mobile Access Gateway is a function on an access router 
   that manages the mobility-related signaling for a mobile node that is 
   attached to its access link''. But by now the MAG is only a half-
   function proxy for the mobile node, because the MAG can only transmit 
   mobility-related signal messages for the mobile node but can not 
   dispose the mobility-related signal messages destined to the mobile 
   node. The MAG is only an active proxy function but does not implement
   reactive agent function in current specification. The function of
   managing the mobility-related signaling defined for MAG is not fully
   introduced by now. 

   Take the Route Optimization procedure as the example. If the mobile 
   node is setting up Route Optimization with a simple IP node which is 
   attached to the MAG, the message flow is as below: 













 
 
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              MN1        HA         LMA       MAG       MN2     
               |         |           |         |         |      
          ===  MN1 attached to HA and MN2 attached to MAG  ===  
      (a) ===  MAG runs PMIP protocol for MN2 (Basic IP)   ===  
          ===  MN1 has no idea about the capability of MN2 ===  
               |         |           |         |         |      
               |   HoTI  |           |         |         |      
      (b)      |------ > |  HoTI     |         |         |      
      (c)      |         |--------- >|  HoTI   |         |      
      (d)      |         |           |------- >|  HoTI   |      
      (e)      |         |           |         |------- >|      
               |         |           |         |ICMP(Err)|      
      (f)      |         |           |         |<--------|      
               |        CoTI         |         |         |      
      (g)      |------------------- >|  CoTI   |         |      
      (h)      |         |           |------- >|  CoTI   |      
      (I)      |         |           |         |------- >|      
               |         |           |         |ICMP(Err)|      
      (j)      |         |           |         |<--------|      
               |ICMP(Err)|           |         |         |      
      (k)      |<--------|           |         |         |      
               |         |           |         |         |      
               |         |           |         |         |      
               |         |           |         |         |      
   
    
                   Figure 1 Issue in Route Optimization. 

    

   The detailed descriptions are as follows: 

   (a) MN1 attached to Home Agent and MN2 attached to MAG, MAG runs PMIP 
       protocol for MN2, which only supports basic IP protocol. During 
       the lifetime of the session between MN1 and MN2, MN1 has no idea 
       about the capability of MN2. 

   (b~e) MN1 initiates a Route Optimization set up and sends Home Test 
         Init message to MN2. The destination address of the packet is 
         the home address of MN2 and the packet goes through HA, LMA and 
         MAG, at last arrives at MN2. 

   (f) MN2 can't recognize the Home Test Init message and replies an 
         ICMP error message to MN1. 

 
 
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   (g~i) MN1 sends Care-of Test Init message to MN2. The destination 
         address of the packet is the home address of MN2 and the packet 
         goes through LMA and MAG, at last arrives at MN2 too. 

   (j) MN2 can't recognize the Care-of Test Init message and replies an 
         ICMP error message to MN1. 

   (k) MN1 receives the ICMP error messages sent by MN2, has to stop 
       Route Optimization set up. 

    

   In this example, Home Test Init message and Care-of Test Init message 
   are both mobility-related signaling, but the MAG doesnot manage or 
   deal these messages for MN2. This miss induces the failure of Route 
   Optimization. 

    

3.2. Motivation 

   The motivation for this extension is based on some mechanisms that 
   have been introduced in IETF. For example, Proxy ARP protocol, which 
   is specified in Using ARP to Implement Transparent Subnet Gateways 
   [RFC1027], has been adopted by lots of routers and gateways. 

   One basic Proxy ARP flow is as below: 



















 
 
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        Host A                    Gateway               Host B    
          |                     e0   |   e1                |      
          |                          |                     |      
      ------- Host A and Host B attached to the Gateway  -------  
          |                          |                     |      
          |    ARP request (IP B)    |                     |      
          |----------------------- > |                     |      
          |                          |                     |      
          |  proxy ARP reply (IP B)  |                     |      
          |< ------------------------|                     |      
          |                          |                     |      
          |     traffic data (IP B)  |                     |      
          |------------------------ >| traffic data (IP B) |      
          |                          |------------------- >|      
          |                          |                     |      
          |                          |                     |      

                     Figure 2 Proxy ARP message flow. 

   In this case, when host A wants to send IP packets to host B, if host 
   A knows only the IP address of host B but doesn't know the MAC 
   address of host B, host A need send out a ARP request message and 
   broadcast the message in MAC layer. The gateway will receive this ARP 
   request, whose destination IP address is the IP address of host B. 
   The destination of this message is not the gateway, but the gateway 
   knows that the destination (i.e. host B) is attached to itself and 
   also knows the destination can't receive this ARP request, so in this 
   situation, the gateway replies an ARP reply message for host B. In 
   the proxy ARP reply message, the source IP address is the IP address 
   of host B and the source MAC address is the MAC address of the e0 
   interface in the gateway. When host A receives this proxy ARP reply 
   message, it can know how to send IP packets to host B. Host A will 
   send IP packets to the gateway (i.e. the e0 interface) and the 
   gateway will forward these packets to host B. 

   Similar to this case, when the MAG in the PMIP domain receives some 
   mobility-related signal messages (e.g. HoTI, CoTI and BU) destined to 
   the mobile node that is attached to its access link, the MAG can also 
   know that the mobile node can't recognize these messages. Since the 
   MAG is the mobility proxy of the mobile node and can manage the 
   mobility-related signaling for the mobile node, it is reasonable for 
   the MAG to dispose these messages on behalf of the mobile node. The 
   MAG MAY work as a reactive mobility agent in this situation. 


 
 
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3.3. Requirement 

   The Route Optimization Agent extension introduced in this document 
   depends on the operation of the MAG. The requirements on the MAG to 
   achieve the extension include following: 

   R1: MAG can recognize mobility-relate signal message. When the MAG 
   receives mobility-related signaling destined to the MN that is 
   attached to its access link, the MAG MAY intercept the messages and 
   reply response messages for the mobile node. Since all the mobility-
   related signal messages contain a mobility header and a MH Type
   field, the MAG can easily fulfill this requirement. 

   R2: MAG can achieve the operation of CN role for Route Optimization 
   specified in [RFC3775]. [RFC5213] has specified some mechanisms for 
   MAG to provide network-based mobility management function and the MAG 
   can create and maintain the Binding Update List as a mobile node
   does, so it is also easy to expand the MAG to create and maintain a
   Binding Cache Entry to meet this requirement. The MAG MAY do more
   agent operation than specified in [RFC5213] as specified in this
   document. 

   R3: MAG can modify the sent-out packets and route the packets to the 
   optimized route basing the created Binding Cache. The MAG MAY check 
   whether a binding cache exists and if the binding cache exists the 
   MAG modifies the destination address in the IP header and includes 
   Type 2 Routing Header in the sent-out packets. The MAG should set the 
   destination address as the care-of address of the destined mobile 
   node and set the Home Address field in the Type 2 Routing Header to 
   the home address of the destined mobile node. 

3.4. Use Case for Agent Extension to Fulfill Route Optimization 

   This document extends the mobility proxy function of the MAG to the 
   full-functional proxy and enables the MAG to manage all the mobility-
   related signaling for the mobile node that is attached to its access 
   link. The use case is as below: 









 
 
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              MN1        HA         LMA       MAG       MN2     
               |         |           |         |         |      
          ===  MN1 attached to HA and MN2 attached to MAG  ===  
       a  ===  MAG runs PMIP protocol for MN2 (Basic IP)   ===  
          ===  MN1 has no idea about the capability of MN2 ===  
               |         |           |         |         |      
               |   HoTI  |           |         |         |      
       b1      |------ > |  HoTI     |         |         |      
       b2      |         |--------- >|  HoTI   |         |      
       b3      |        CoTI         |------- >|         |      
       c1      |------------------- >|   HoT   |         |      
       d1      |         |           |< -------|         |      
               |         |           |  CoTI   |         |      
       c2      |         |    HoT    |------- >|         |      
       d2      |   HoT   |< ---------|         |         |      
       d3      |< -------|           |  CoT    |         |      
       e1      |        CoT          |< -------|         |      
       e2      |< -------------------|         |         |      
               |                     |         |         |      
               |                     |         |         |      
               |         BU          |         |         |      
       f1      |------------------- >|    BU   |         |      
       f2      |                     |------- >|         |      
               |                     |Binding Ack        |      
       g1      |    Binding Ack      |< -------|         |      
       g2      |< -------------------|         |         |      
               |    Traffic data     |         |         |      
              -|------------------- >| Traffic |         |      
             / |                     |------- >| Traffic |      
            /  |                     |         |------- >|      
       h   |   |                     |         | Traffic |      
            \  |                     | Traffic |< -------|      
             \ |    Traffic data     |< -------|         |      
              -|< -------------------|         |         |      
               |                     |         |         |      

    
              Figure 3 Agent extension in Route Optimization. 

    

   The detailed descriptions are as follows: 

   (a) MN1 attached to Home Agent and MN2 attached to MAG, MAG runs PMIP 
       protocol for MN2, which only supports basic IP protocol. During 
 
 
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       the lifetime of the session between MN1 and MN2, MN1 has no idea 
       about the capability of MN2. 

   (b1~b3) MN1 initiates a Route Optimization set up and sends Home Test 
         Init message to MN2. The destination address of the packet is 
         the home address of MN2 and the packet goes through HA and LMA 
         and reaches MAG. 

   (c1~c2) MN1 sends Care-of Test Init message to MN2. The destination 
         address of the packet is the home address of MN2 and the packet 
         goes through LMA and reaches MAG too. 

   (d1~d3) MAG recognizes the Home Test Init message, which is a 
         mobility-related signaling, and generates a Home Test message 
         on behalf of MN2. The procedure for the MAG to generate the 
         Home Test message is as the same with CN's operation specified 
         in section 9.4.1 and section 9.4.3 of [RFC3775]. The MAG 
         transmits Home Test message to MN1 and the packet goes through 
         LMA and HA and arrives at MN1 at last. 

   (e1~e3) MAG recognizes the Care-of Test Init message, which is a 
         mobility-related signaling, and generates a Care-of Test 
         message on behalf of MN2. The procedure for the MAG to generate 
         the Care-of Test message is as the same with CN's operation 
         specified in section 9.4.2 and section 9.4.4 of [RFC3775]. The 
         MAG transmits Care-of Test message to MN1 and the packet goes 
         through LMA and arrives at MN1 at last. 

   (f1~f2) MN1 receives Home Test and Care-of Test message and sends 
         Binding Update message to the address of MN2 as specified in 
         [RFC3775]. The Binding Update message also reaches the MAG 
         which the MN2 attached to. 

   (g1~g2) MAG recognizes the Binding Update message, which is a 
         mobility-related signaling, and caches the Home Address, Care-
         of Address and bindings on behalf of MN2. The procedure is as 
         the same with CN's operation as specified in section 9.5.1 of 
         [RFC3775]. The MAG also includes the IP address of the attached 
         IP node (i.e. the destination of the Binding Update message) in 
         the binding cache. The MAG transmits Binding Ack message to MN1 
         and the packet goes through LMA and arrives at MN1 at last. 

   (h) Route Optimization is achieved and Home Agent of MN1 is not 
       involved in the traffic data transport. For the traffic flow 
       from MN1 to MN2, the MAG forwards all the traffic packets basing 
       on the destination address of the packets. For the traffic flow 

 
 
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       from MN2 to MN1, the MAG achieves the operation specified in 
       section 4.1.2. 

    

    

4. Solution and Operation Consideration 

4.1. MAG Operation 

   The MAG is a function that typically runs on an access router. The 
   MAG transfers all the IP packets from or destined to the mobile node 
   that is attached to its access link. However, some more operation is 
   defined in this document for the expansion solution. 

   The operations for Route Optimization Agent Function consist of 
   following: 

   o  Intercepting and disposing the mobility-related signaling destined 
      to the attached mobile node. 

   o  Creating, maintaining and deleting the binding cache for the 
      mobile node to which the initiator wants to establish or release 
      a Route Optimization. 

   o  Destination Address replacement for the outgoing traffic from the 
      attached mobile node. 

   o  Security operation for the Return Routability Procedure and Route 
      Optimization. The MAG SHOULD works as specified in section 5.2 
      and section 15.4 in [RFC5213] for the role of correspondent node, 
      if the MAG runs the Route Optimization Agent Function. 

    

   Editor Note:  

       The introduced Route Optimization Agent Function in the reflector 
       may even be separate with the active Proxy Mobile IP function 
       introduced in [RFC5213]. This is to say that the binding cache 
       management and the binding update list management may be 
       independent. The details need more consideration and discussion. 

    


 
 
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4.1.1. Incoming Flow Transmission 

   For the incoming (i.e. from the remote IP node to the IP node that is 
   attached to the access link of the MAG) flow, the MAG needs parse the 
   IP header to check the packet type as soon as it receives the packet 
   from the remote IP node. 

   If the IP packets received from other IP nodes don't contain mobility 
   header, the IP packets are not mobility-related signaling, the MAG 
   works as a normal router for these non-mobility-related IP packets. 

   If the IP packets received from other IP nodes contain the mobility 
   header, the MAG needs further check the MH type field in the mobility 
   header. The MAG MAY execute the expansion solution for these 
   mobility-related packets.  

   When the received packet is Home Test Init Message, the MAG stops 
   transferring the packet to the attached IP node and executes the 
   operation as specified for the correspondent node role in section 
   9.4.1 and 9.4.3 of [RFC3775]. 

   When the received packet is Care-of Test Init Message, the MAG stops 
   transferring the packet to the attached IP node and executes the 
   operation as specified for the correspondent node role in section 
   9.4.2 and 9.4.4 of [RFC3775]. 

   When the received packet is Binding Update message, the MAG stops 
   transferring the packet to the attached IP node and executes the 
   operation as specified for the correspondent node role in section 
   9.5.1 and 9.5.4 of [RFC3775]. 

    

4.1.2. Outgoing Flow Transmission 

   For the outgoing (i.e. from the IP node that is attached to the 
   access link of the MAG to the remote IP node) flow, the MAG needs 
   examine its Binding Cache for an entry for the address pair (i.e. the 
   source address and the destination address of the IP packet) as soon 
   as it receives the packet from the attached IP node. 

   If no corresponding binding cache entry exists, the MAG works as a 
   normal MAG for these packets. 

   If a corresponding binding cache entry exists, it means Route 
   Optimization has been established between the IP node pair. The MAG 
   MAY use a type 2 routing header to route the packet to the 
 
 
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   destination node by way of its care-of address. However, the MAG MUST 
   NOT do this in the following cases: 

   o  When forwarding an IPv6 Neighbor Discovery packet. 

   o  When forwarding the packets that are noted in Section 6.1 of 
      [RFC3775]. 

   The MAG may implement following operation for Route Optimization: 

   o  The MAG inserts the Type 2 routing header and sets the Home 
      Address in the routing header to the remote mobile node's home 
      address (the original destination address to which the packet was 
      being sent). 

   o  The MAG sets the Destination Address in the packet's header to the 
      remote mobile node's care-of address copied from the Binding 
      Cache entry. 

   o  The MAG forwards the modified packet as specified in section 
      6.10.5 of [RFC5213]. 

    

   Note that the implementation creates some additional requirements for 
   path MTU discovery since the modification changes the packet size. 
   The MAG should choose an appropriate way to indicate the sending IP 
   node this situation. 

    

4.1.3. Conceptual Data Structures 

   Every MAG maintains a Binding Update List Entry as specified in 
   [RFC3775] and this document adds Binding Cache to the MAG. When the 
   MAG receives the Binding Update message destined to the attached 
   mobile node the MAG creates the binding cache entry and associates 
   the entry to the destination mobile node. 

   The newly introduced Binding Cache Entry for this extension contains 
   two additional fields than the data structure specified in section 
   9.1 of [RFC3775]. 

   o  The binding cache entry contains a flag indicating whether or not 
      this binding cache is a agent binding cache entry.  


 
 
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   o  The binding cache entry contains an associated mobile node
      address, which is the true destination of the intercepted Binding
      Update message. 

   Each binding cache is mapped with an address pair (i.e. the home 
   address of the RO-initiator mobile node and the IP address of the 
   attached mobile node). The binding cache contains the care-of address 
   of the RO-initiator mobile node as specified in section 9.1 of 
   [RFC3775]. Route Optimization may be applied between the address
   pair. 
    

4.2. Operation in Other Network Element 

   The extension mechanism introduced in this document doesn't impact 
   the operation in MN, HA, LMA and CN. These network elements follow 
   the operation described in other specification. 

    

5. Security Considerations 

   The extension in this document is just to expand the scope of the 
   mobility management to cover the reactive mobility management agent 
   function, such as the acceptance of Route Optimization, and the MAG 
   still follows the principle that providing network-based mobility 
   management to the mobile node that is attached to its access link. So 
   this extension brings no new security issue to mobility management. 

   But this extension needs the MAG to implement packet inspection on 
   the packets destined to the mobile node, which would impact the 
   performance of the MAG and maybe bring some security risk. By the 
   time when this document is written, no explicit security problem has 
   been found and the accurate security consideration needs to be 
   further studied. 

    

6. IANA Considerations 

   This document has no actions for IANA. 

    




 
 
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7. Acknowledgments 

   The author would like to thank Netext Working Group for the review, 
   comment and discussion. 

    








































 
 
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APPENDIX A: Future Extension and Use Case 

A.1. Extension for Mobile Router in NEMO 

   This solution can also be applied in Network Mobility (NEMO) 
   extension, in which the Mobile Router provides mobility management 
   for IP node with only support for basic IP. The extension for NEMO is 
   as below: 

                                                                
              MN1       HA1         HA2        MR       MN2     
               |         |           |         |         |      
          ===  MN1 attached to HA and MN2 attached to MR   ===  
       a  ===  MR provides mobility management for MN2     ===  
          ===  MN1 has no idea about the capability of MN2 ===  
               |         |           |         |         |      
               |   HoTI  |           |         |         |      
       b1      |------ > |  HoTI     |         |         |      
       b2      |         |--------- >|  HoTI   |         |      
       b3      |        CoTI         |------- >|         |      
       c1      |------------------- >|   HoT   |         |      
       d1      |         |           |< -------|         |      
               |         |           |  CoTI   |         |      
       c2      |         |    HoT    |------- >|         |      
       d2      |   HoT   |< ---------|         |         |      
       d3      |< -------|           |  CoT    |         |      
       e1      |        CoT          |< -------|         |      
       e2      |< -------------------|         |         |      
               |                     |         |         |      
               |                     |         |         |      
               |         BU          |         |         |      
       f1      |------------------- >|    BU   |         |      
       f2      |                     |------- >|         |      
               |                     |Binding Ack        |      
       g1      |    Binding Ack      |< -------|         |      
       g2      |< -------------------|         |         |      
               |    Traffic data     |         |         |      
              -|------------------- >| Traffic |         |      
             / |                     |------- >| Traffic |      
            /  |                     |         |------- >|      
       h   |   |                     |         | Traffic |      
            \  |                     | Traffic |< -------|      
             \ |    Traffic data     |< -------|         |      
              -|< -------------------|         |         |      
               |                     |         |         |      
    
              Figure 4 Agent extension in Route Optimization. 
 
 
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Internet-Draft   Route Optimization Agent Extension       October 2009 
    

    

   In this extension, Mobile Router manages the mobility-related 
   signaling destined to the mobile node that is attached to its access 
   link. Mobile Router responds Care-of Test and Home Test message and 
   manages the binding cache on behalf of the MN. 

    

A.2. Extension for IPv4/MIP4 

   TBD. 

    

8. References 

8.1. Normative References 

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

   [RFC3775] Johnson, D., Perkins, C., and J. Arkko, "Mobility Support 
             in IPv6", RFC 3775, June 2004. 

   [RFC5213] Sri, G., Kent, L., Vijay, D. Kuntal, C. and Basavaraj, P., 
             "Proxy Mobile IPv6", RFC 5213, August 2008. 

8.2. Informative References 

   [RFC1027] Smoot, C. and John Q., "Using ARP to Implement Transparent 
             Subnet Gateways", RFC1027, October 1987. 

Author's Addresses 

   Xiangsong Cui 
   Huawei Technologies 
   KuiKe Bld., No.9 Xinxi Rd., 
   Shang-Di Information Industry Base,  
   Hai-Dian District, Beijing, P.R. China, 100085 
      
   Email: Xiangsong.Cui@huawei.com 
    




 
 
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PAFTECH AB 2003-20262026-04-24 08:02:09