One document matched: draft-wu-mip4-ether-00.txt


Network Working Group                                           Q. Wu 
                                                             T.Taylor 
Internet Draft                                                 Huawei 
                                                               H.Deng
                                                         China Mobile 
Intended status: Standard Track                         March 3, 2009 
Expires: September 2009 
                                   
 
                                      
                MIP Extension for Ethernet Service Support 
                        draft-wu-mip4-ether-00.txt 


Status of this Memo 

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

   This Internet-Draft is submitted to IETF in full conformance with the 
   provisions of BCP 78 and BCP 79. This document may not be modified, 
   and derivative works of it may not be created, and it may not be 
   published except as an Internet-Draft. 

   This Internet-Draft is submitted to IETF in full conformance with the 
   provisions of BCP 78 and BCP 79. This document may not be modified, 
   and derivative works of it may not be created, except to publish it 
   as an RFC and to translate it into languages other than English. 

   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 August 3, 2009. 



 
 
 
Wu                   Expires September 3, 2009               [Page 1] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

Copyright Notice 

   Copyright (c) 2009 IETF Trust and the persons identified as the 
   document authors. All rights reserved. 

   This document is subject to BCP 78 and the IETF Trust's Legal 
   Provisions Relating to IETF Documents 
   (http://trustee.ietf.org/license-info) in effect on the date of 
   publication of this document. Please review these documents carefully, 
   as they describe your rights and restrictions with respect to this 
   document. 

Abstract 

   The IP Mobility Protocol [RFC3344] enables node to maintain IP 
   connectivity when node changes the location. However it is ideal to 
   support forwarding ethernet frame between mobile node and ethernet 
   service provider. This document describes ethernet extension mobility 
   option for mobile IPv4 that is intended to assist home agent to 
   tunnel ethernet frame on the home link to the FA in the foreign link 
   during datagram delivery process. 

Table of Contents 

    
   1. Introduction.................................................3 
   2. Conventions used in this document............................3 
   3. Scenarios for MIP based Ethernet Services....................4 
      3.1. Coexistence of services for the same access network.....4 
      3.2. Switched Ethernet Access Network........................5 
   4. Processing Consideration.....................................6 
      4.1. GRE Encapsulation Support...............................6 
      4.2. Ethernet Service Support................................6 
   5. Mobile Node Consideration....................................7 
   6. Foreign Agent Consideration..................................7 
      6.1. Extension to registration tables for the foreign Agent..7 
      6.2. Foreign Agent Operation.................................7 
   7. Home Agent Consideration.....................................8 
      7.1. Extension to registration tables for the home Agent.....8 
      7.2. Home Agent Operation....................................8 
   8. Message Format...............................................9 
      8.1. Ethernet Extension Mobility Option......................9 
      8.2. GRE Extension option....................................9 
   9. Security Considerations......................................9 
   10. IANA Considerations........................................10 
   11. References.................................................10 
      11.1. Normative References..................................10 
 
 
Wu                   Expires September 3, 2009               [Page 2] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

      11.2. Informative References................................10 
    
1. Introduction 

   The IP Mobility Protocol [RFC3344] enables node to maintain IP 
   connectivity when node changes the location. However in some mobile 
   IPv4 scenarios, enable node to maintain IP connectivity is not enough 
   to support forwarding ethernet frame between mobile node and ethernet 
   service provider (e.g. ASP), i.e. ethernet support.  
   The capability to support ethernet service can facilitate mobility 
   service providers to provider IP services as well as ethernet 
   services concurrently over the same infrastructure within the same 
   mobility service subscription. For example: 
      o Provide end to end ethernet connectivity from the mobile node 
        across access network to the ASP providing ethernet services 
        (e.g. connectivity to DSL network with PPPoE). 
      o Ethernet service support within the access network, e.g., node 
        movement from one ethernet segment to another within the same 
        access network. It allows transport ethernet frame between 
        mobile node and the mobility anchor(e.g. FA) 
      o Provide ethernet aggregation for the public access service which 
        imposes ethernet frame to pass through ISP-head end to enable 
        accouting and enforce security policies. 
   This document describes ethernet extension mobility option for mobile 
   IPv4 that is intended to assist home agent to tunnel ethernet frame 
   on the home link to the FA in the foreign link during datagram 
   delivery process after the binding registration procedure. Ethernet 
   service support for mobile IPv4 may affect the home agent routing 
   decision, home address assignment polices and tunnel setup mechanism. 
   Support of Ethernet does not require a new network architecture or 
   any new functional entities in the network. The support of Ethernet 
   Services is smoothly integrated into the Mobile network architecture 
   and Ethernet services can be operated parallel to the IP Services in 
   the same network. 
    

2. Conventions used in this document 

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

 
 
Wu                   Expires September 3, 2009               [Page 3] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

   The document uses the terminology specified in [RFC 3344]. In 
   addition, this document defines the following: 

   Ethernet Extension 

   Ethernet support for Mobile IPv4 that assists home agent to tunnel 
   ethernet frame on the home link to the FA in the foreign link during 
   datagram delivery process after the binding registration procedure. 

   GRE Extension 

   GRE Encapsulation support for Mobile IPv4 that is used to 
   differentiate between difference Ethernet services or flows 

3. Scenarios for MIP based Ethernet Services 

In this section, two use cases are listed that are identified for 
Ethernet Service Support: Coexistence of IP services and Ethernet 
services for the same Access network, Switched Ethernet access network. 

3.1. Coexistence of services for the same access network 

The figure 1 shows coexistence of IP services and Ethernet service for 
the same access network. In this scenario, the ASP in the fixed network 
provides ethernet service contains the bridging function for forwarding 
Ethernet frames between MN and the Ethernet Service provider while the 
MSP in the mobile network provides IP service (e.g., Internet) delivered 
between the foreign agent and the home agent through the same access 
network. When Mobile IP is applied for dynamic tunnel management between 
the foreign agent and the home Agent, the GRE based tunnel enables the 
transport of Ethernet frames in the payload. The Ethernet frames are 
forwarded based on the MN MAC address. When the MN is not the end system 
but contains a bridge forwarding to end systems behind the MN, the 
downlink Ethernet frames contain destination MAC addresses other than 
the MN MAC address. 











 
 
Wu                   Expires September 3, 2009               [Page 4] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

                                                +-----------+ 
                      ---------                 | ASP       | 
                   ///         \\\              | Providing | 
    +-------+      Access Network \             | Ethernet  | 
    |       |    |      +------+   |   +------ /| Service   | 
    |  MN   |   |       |  FA  +----+--+  HA  X +-----------+ 
    +-------+   |       +------+    |  +------+\ 
                 |                 |            \   ----- 
                  \               /              \//     \\ 
                   \\\         ///               | Internet| 
                      ---------                   \\     // 
                                                    ----- 
       Figure 1 Coexistence of IP services and Ethernet 
             services for the same access network 
3.2. Switched Ethernet Access Network 

Figure 2 shows one use case for interoperable implementations of various 
access networks in which Ethernet aggregation is used instead of IP-
based tunnels for the data paths between the foreign agent in different 
access network and the home agent in the core network. The ASP in the 
fixed network provides ethernet service contains the bridging function 
for forwarding Ethernet frames to the home agent. In this scenario, each 
access network is connected on the network side to the Core network via 
an Ethernet aggregation network for concentration and forwarding of the 
data path. The IP-based control plane between the access network and the 
Core network is also carried over the Ethernet aggregation network. The 
particular Ethernet protocol for the data path mentioned above is not 
specified and depends on the kind of services provided by the Core 
network to the MN or the host behind the MN. Here the host is the end 
system behind the MN. 
















 
 
Wu                   Expires September 3, 2009               [Page 5] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

               Access Network 1 
    +-------+        /---------\ 
    |       |    ////  +------+ \\\\ 
    |  MN   |   |      |  FA  +-----|                 +-----------+ 
    +-------+   |      +------+     \    +--------+   | ASP       | 
       |         \\\\           ////  \  |        +---+ Providing | 
       |             \---------/        \|   HA   |   | Ethernet  | 
       |             /---------\        /+--------+   | Service   | 
       |       Access Network 2 \\\\  /               +-----------+ 
    +--\/---+   |      +------+     / 
    |       |   |      |  FA  +-----| 
    |  MN   |    \\\\  +------+ //// 
    +-------+        \---------/ 
            Figure 2 Switched Ethernet access network 
4. Processing Consideration 

4.1. GRE Encapsulation Support 

[RFC2003] allows IP in an IP encapsulation which can be used to tunnel 
traffic between the FA and the HA. However this encapsulation method is 
not enough to identify the destination of packets of a specific flow. 
[RFC2890] describes one generic routing encapsulation method which can 
be used to distinguish different flows in terms of GRE key. Thus, GRE 
encapsulation is one best way to differentiate between difference 
Ethernet services or flows, i.e., during binding registration procedure, 
the message exchange between the FA and the HA will be used to negotiate 
downlink and uplink GRE keys which is used to marking downlink and 
uplink traffic for a specific flow. 

4.2. Ethernet Service Support 

In order to support Ethernet service delivery in mobile IPv4 scenario, 
the communication between the MN and the home agent needs to be modified 
to support Ethernet frame. Ethernet frame can be carried over IP tunnel 
or Ethernet aggregation network between the foreign agent and the home 
agent. During binding registration procedure, the FA must on behalf of 
MN send registration request message to the home agent with MN's MAC 
address included in the ethernet extension mobility option, meanwhile 
the FA will bind MN's MAC address, GRE key to the FA CoA in its own 
registration tables. Upon receiving registration request, the home agent 
will establish binding among MN's MAC address, GRE key and the FA CoA in 
its own registration tables. Also it can learn the MAC addresses of the 
hosts behind the MN and establish binding between these MAC addresses 
and FA CoA in its own registration tables when those hosts become active 
and send some uplink frames. 


 
 
Wu                   Expires September 3, 2009               [Page 6] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

5. Mobile Node Consideration 

If the mobile node is capable of supporting Ethernet service, it should 
be authenticated for network access and authorized for the specific 
Ethernet service. After that, a set of pre-provisioned service flows for 
Ethernet service and IP service can be created, admitted and activated 
between the MN and the foreign agent. 

6. Foreign Agent Consideration 

6.1. Extension to registration tables for the foreign Agent 

Every foreign agent maintains a registration table for each currently 
attached mobile node, as explained in section 3.8.1 of the mobile IPv4 
specification [RFC3344]. To support this specification, the conceptual 
registration table data structure must be extended with the following 
two new additional fields. 

The MN's MAC address 

The MN's MAC address used to bind with FA CoA during binding 
registration procedure and tunnel Ethernet frame to MN's MAC address 

The hosts MAC address behind MN 

The hosts MAC address behind MN used to bind with FA CoA when learning 
it from uplink frame received from host behind MN. 

The MN's GRE key 

The MN's GRE key assigned by the FA and the HA and used to distinguish 
the destination of packets of a specific flow which include uplink GRE 
key and downlink GRE key. 

6.2. Foreign Agent Operation 

In the foreign agent care-of address mode [RFC3344], during binding 
registration procedure, the FA starts the establishment of a dynamic 
tunnel by sending or forwarding the Registration Request message to the 
indicated HA. The Registration Request will contain the MN's NAI 
[RFC2794], IPv4 home address field will be set to all zeros and the MN's 
MAC address will be included in the new MIPv4 extension called Ethernet 
extension. When the FA forwards the Registration Request to the home 
agent with MN's MAC address carried in the ethernet extension mobility 
option, it will bind MN's MAC address, GRE key to the FA CoA in its own 
registration tables. Also it requests GRE encapsulation to differentiate 
between difference Ethernet services or flows. In addition to setting 
 
 
Wu                   Expires September 3, 2009               [Page 7] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

the G flag in Registration Request message, the FA will also allocate 
the GRE key and will include it in the GRE extension. 

Upon receiving frame tunneled by home agent on the home link after 
binding registration, the FA will identify the MN to which the frame 
must be delivered. The FA will not use the data from the inner packet 
header (i.e. MAC addresses) to identify the corresponding MN. The 
received GRE key will be used to identify the MN to which the 
encapsulated payload must be delivered. This is advantageous in case 
that there are multiple devices connected to a bridge behind MN. 

 

7. Home Agent Consideration 

7.1. Extension to registration tables for the home Agent 

Every home agent maintains a registration tables for each currently 
attached mobile node, as explained in section 3.8.1 of the mobile IPv4 
specification [RFC3344]. To support this specification, the conceptual 
registration table data structure must be extended with the following 
two new additional fields. 

The MN's MAC address 

The MN's MAC address used to bind with FA CoA during binding 
registration procedure and tunnel Ethernet frame to MN MAC address 

The hosts MAC address behind MN 

The hosts MAC address behind MN used to bind with FA CoA when learning 
it from uplink frame received from host behind MN. 

The MN's GRE Key 

The MN's GRE key assigned by the FA and the HA and used to distinguish 
the destination of packets of a specific flow which include uplink GRE 
key and downlink GRE key. 

7.2. Home Agent Operation 

When the home agent receives the Registration Request message from the 
the foreign agent, it will bind the MN's MAC address contained in the 
Ethernet extension to the FA CoA(i.e., IP address of FA). It will also 
save the received GRE key as part of its mobility binding context. Home 
agent will also allocate its own GRE key and send it to FA in MIP 
Registration Reply. 
 
 
Wu                   Expires September 3, 2009               [Page 8] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

After successful registration, the home agent will start capturing the 
Ethernet frames on the home link destined to the registered MN's MAC 
address and forwarding those frames to the FA via GRE tunnel. The home 
agent must include the FA's GRE key in the GRE packet header. In some 
case, the bridge attached to the home agent can learn the MAC addresses 
of the hosts behind the MN and establish binding between these MAC 
addresses and FA CoA when those hosts become active and send some uplink 
frames. Having learnt the address(es) behind the MN, the bridge behind 
the home agent would start tunneling the frames on the home link 
destined to those MAC addresses over the established GRE tunnel, tagging 
the tunneled packets with the GRE key associated with the MN. Upon 
receiving frame in the uplink direction from the foreign agent, the home 
agent will use the received GRE key (instead of the source address from 
the inner header) to find the corresponding mobility context.  

8. Message Format 

8.1. Ethernet Extension Mobility Option 

A new mobility option, the Ethernet Extension mobility option, is 
defined for use in the Registration request and registration response 
messages exchanged between the foreign agent and the home agent. This 
option can be used for the Home agent and the foreign to identify the MN 
to which the frame must be delivered. 

     0                   1                   2                   3 
     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    |  Type = TBD   |   Length      |          Reserved             | 
   -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    |                    MN MAC Address 
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                  Figure 3 Ethernet Extension Mobility Option 
8.2. GRE Extension option 

The details are defined in section 5 of [draft-yegani-gre-key-extension-
03]. 

9. Security Considerations 

The Ethernet Extension Mobility Option and the functionalities in this 
document are protected by the Authentication Extensions described in 
[RFC3344]. The FA needs to have a security association with the HA to 
register the MN's IP address. The security association can be 
provisioned by the administrator, or dynamically derived. 


 
 
Wu                   Expires September 3, 2009               [Page 9] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

10. IANA Considerations 

11. References 

11.1. Normative References 

   [RFC3344] Perkin, C., " IP Mobility Support for IPv4 ", RFC 3344, 
             August 2002. 

   [RFC2003] Perkin, C.,Solomo, J., " IP Encapsulation within IP ", RFC 
             2003, October, 1996. 

   [RFC2794] Calhoun, P. and C. Perkins, "Mobile IP Network Access 
             Identifier Extension for IPv4", RFC 2794, March 2000. 

   [RFC2890] Dommety, G., " Key and Sequence Number Extensions to GRE ", 
             RFC 2890, September, 2000. 

11.2. Informative References 

   [draft-yegani-gre-key-extension-03] Yegani, P., Dommety, G., " GRE 
             Key Extension for Mobile IPv4 ", draft-yegani-gre-key-
             extension-03,June,2007. 























 
 
Wu                   Expires September 3, 2009              [Page 10] 

Internet-Draft  MIP Extension for Ethernet Service Support   March 2009 
    

Authors' Addresses 

   Qin Wu 
   Huawei Technologies Co.,Ltd 
   Site B,Floor 12F,Huihong Mansion,No.91,Baixia Rd. 
   Nanjing 210001 
   China 
      
   Phone: +86-25-84565892 
   Email: Sunseawq@huawei.com 
 

   Tom Taylor 
   Huawei Technologies Co.,Ltd  
   1852,Lorraine Ave 
   Ottawa,Ontario K1H 6Z8 
   Canada 
      
   Email: tom.taylor@rogers.com 
 

   Hui Deng 
   China Mobile 
   53A, Xibianmennei Ave., 
   Xuanwu District, 
   Beijing 100053 
   China 
      
   Email: denghui02@gmail.com 
    
















 
 
Wu                   Expires September 3, 2009              [Page 11] 


PAFTECH AB 2003-20262026-04-23 14:46:39