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Softwire Mesh Management Information Base (MIB)
draft-ietf-softwire-mesh-mib-02

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 7856.
Authors Yong Cui , Jiang Dong , Peng Wu , Mingwei Xu
Last updated 2013-02-23
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draft-ietf-softwire-mesh-mib-02
Softwire                                                          Y. Cui
Internet-Draft                                                   J. Dong
Intended status: Standards Track                                   P. Wu
Expires: August 28, 2013                                           M. Xu
                                                     Tsinghua University
                                                       February 24, 2013

            Softwire Mesh Management Information Base (MIB)
                    draft-ietf-softwire-mesh-mib-02

Abstract

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   In particular it defines objects for managing softwire mesh
   [RFC5565].

Status of This Memo

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

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   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."

   This Internet-Draft will expire on August 28, 2013.

Copyright Notice

   Copyright (c) 2013 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
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   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as

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   described in the Simplified BSD License.

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  The Internet-Standard Management Framework . . . . . . . . . .  3
   3.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   4.  Conventions  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   5.  Structure of the MIB Module  . . . . . . . . . . . . . . . . .  3
     5.1.  The swmSupportedTunnlTable Subtree . . . . . . . . . . . .  3
     5.2.  The swmEncapsTable Subtree . . . . . . . . . . . . . . . .  4
     5.3.  The swmBGPNeighborTable Subtree  . . . . . . . . . . . . .  4
     5.4.  The swmMIBConformance Subtree  . . . . . . . . . . . . . .  4
   6.  Relationship to Other MIB Modules  . . . . . . . . . . . . . .  4
     6.1.  Relationship to the IF-MIB . . . . . . . . . . . . . . . .  4
     6.2.  Relationship to the IP Tunnel MIB  . . . . . . . . . . . .  5
     6.3.  MIB modules required for IMPORTS . . . . . . . . . . . . .  5
   7.  Definitions  . . . . . . . . . . . . . . . . . . . . . . . . .  5
   8.  Security Considerations  . . . . . . . . . . . . . . . . . . . 11
   9.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 11
   10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
   11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
     11.1. Normative References . . . . . . . . . . . . . . . . . . . 12
     11.2. Informative References . . . . . . . . . . . . . . . . . . 12
     11.3. URL References . . . . . . . . . . . . . . . . . . . . . . 13

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1.  Introduction

   Softwire mesh framework RFC 5565 [RFC5565] is a tunneling mechanism
   which enables connectivity between islands of IPv4 networks across
   single IPv6 backbone and vice versa.  In softwire mesh, extended
   multiprotocol-BGP (MP-BGP)is used to set up tunnels and advertise
   prefixes among address family border routers (AFBRs).

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   In particular it defines objects for managing softwire mesh
   [RFC5565].

2.  The Internet-Standard Management Framework

   For a detailed overview of the documents that describe the current
   Internet-Standard Management Framework, please refer to section 7 of
   RFC 3410 [RFC3410].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  MIB objects are generally
   accessed through the Simple Network Management Protocol (SNMP).  They
   are defined using the mechanisms stated in the Structure of
   Management Information (SMI).  This memo specifies a MIB module that
   is compliant to the SMIv2, which is described in STD 58, RFC 2578
   [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580].

3.  Terminology

   This document uses terminology from softwire problem statement RFC
   4925 [RFC4925] and softwire mesh framework RFC5565 [RFC5565].

4.  Conventions

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

5.  Structure of the MIB Module

   The softwire mesh MIB provides a method to configure and manage the
   softwire mesh objects through SNMP.

5.1.  The swmSupportedTunnlTable Subtree

   Since AFBR need to negotiate with BGP peer what kind of tunnel they
   will use, it should firstly announce the types of tunnels it
   supports.  The swmSupportedTunnlTable subtree provides the

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   information.  According to section 4 of RFC 5512[RFC5512], current
   softwire mesh tunnel types include IP-IP, GRE and L2TPv3.

5.2.  The swmEncapsTable Subtree

   The swmEncapsTable subtree provides softwire mesh NLRI-NH information
   about the AFBR.  It keeps the mapping between E-IP prefix and I-IP
   address of next hop.  The mappings determine which I-IP destination
   address will be used to encapsulate the received packet's according
   to its E-IP destination address.  The definitions of E-IP and I-IP
   are explained in section 4.1 of RFC 5565[RFC5565].

5.3.  The swmBGPNeighborTable Subtree

   The subtree provides softwire mesh BGP neighbor information of an
   AFBR.  It includes the address of the softwire mesh BGP peer, and the
   kind of tunnel that the AFBR would use to communicate with this BGP
   peer.

5.4.  The swmMIBConformance Subtree

   The subtree provides conformance information of MIB objects.

6.  Relationship to Other MIB Modules

6.1.  Relationship to the IF-MIB

   The Interfaces MIB [RFC2863] defines generic managed objects for
   managing interfaces.  Each logical interface (physical or virtual)
   has an ifEntry.  Tunnels are handled by creating logical interfaces
   (ifEntry).  Being a tunnel, softwire mesh has an entry in the
   Interface MIB, as well as an entry in IP Tunnel MIB.  Those
   corresponding entries are indexed by ifIndex.

   The ifOperStatus in the ifTable would be used to represents whether
   the mesh function of the AFBR has been triggered.  If the software
   mesh capability is negotiated during the BGP OPEN phase, the mesh
   function is considered to be started, and the ifOperStatus is "up".
   Otherwise the ifOperStatus is "down".

   In the case of IPv4-over-IPv6 softwire mesh tunnel, the ifInUcastPkts
   counts the number of IPv6 packets which are sent to the virtual
   interface for decapsulation into IPv4.  The ifOutUcastPkts counts the
   number of IPv6 packets which are generated by encapsulating IPv4
   packets sent to the virtual interface.  Particularly, if these IPv4
   packets need fragmentation, ifOutUcastPkts counts the number of
   packets after fragmentation.

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   In the case of IPv6-over-IPv4 softwire mesh tunnel, the ifInUcastPkts
   counts the number of IPv4 packets, which are sent to the virtual
   interface for decapsulation into IPv6.  The ifOutUcastPkts counts the
   number of IPv4 packets, which are generated by encapsulating IPv6
   packets sent to the virtual interface.  Particularly, if these IPv6
   packets need to be fragmented, tifOutUcastPkts counts the number of
   packets after fragmentation.  Similar definition apply to other
   counting objects in ifTable.

6.2.  Relationship to the IP Tunnel MIB

   The IP Tunnel MIB [RFC4087] contains objects applicable to all IP
   tunnels, including softwire mesh.  On the other hand, Softwire Mesh
   MIB extends the IP tunnel MIB to further describe encapsulation-
   specific information.

   Running a point to multi-point tunnel, it is necessary for a softwire
   mesh AFBR to maintain an encapsulation table, used to perform correct
   "forwarding" among AFBRs.  This forwarding on an AFBR is performed by
   using the E-IP destination address to look up the I-IP encapsulation
   destination address in the encapsulation table.  An AFBR also needs
   to know the BGP peer information of the other AFBRs, so that it can
   negotiate the NLRI-NH information and the tunnel parameters with
   them.

   Softwire mesh requires the implmentation of the IP Tunnel MIB.  The
   tunnelIfEncapsMethod in the tunnelIfEntry should be set to
   softwireMesh("xx"), and corresponding entry in the softwire mesh MIB
   module will exist for this tunnelIfEntry.  The
   tunnelIfRemoteInetAddress must be set to 0.0.0.0 for IPv4 or :: for
   IPv6 because it is a point to multi-point tunnel.

   Since tunnelIfAddressType in tunnelIfTable represents the type of
   address in the corresponding tunnelIfLocalInetAddress and
   tunnelIfRemoteInetAddress objects, we can use this semantic to
   specify the type of the softwire mesh, which is either IPv4-over-IPv6
   or IPv6-over-IPv4.  When tunnelIfAddressType is IPv4, the mesh is
   IPv6-over-IPv4; When tunnelIfAddressType is IPv6, the encapsulation
   would be IPv4-over-IPv6.

6.3.  MIB modules required for IMPORTS

   The following MIB module IMPORTS objects from SNMPv2-SMI [RFC2578],
   SNMPv2-TC [RFC2579], SNMPv2-CONF [RFC2580], IF-MIB [RFC2863] and
   INET-ADDRESS-MIB [RFC4001].

7.  Definitions

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SOFTWIRE-MESH-MIB DEFINITIONS ::= BEGIN

IMPORTS
    MODULE-IDENTITY, OBJECT-TYPE, transmission  FROM SNMPv2-SMI

    OBJECT-GROUP, MODULE-COMPLIANCE             FROM SNMPv2-CONF

    InetAddress, InetAddressPrefixLength         FROM INET-ADDRESS-MIB

    ifIndex                                     FROM IF-MIB

    IANAtunnelType                              FROM IANAifType-MIB;

swmMIB MODULE-IDENTITY
    LAST-UPDATED "201302180000Z"        -- February 18, 2013
    ORGANIZATION "Softwire Working Group"
    CONTACT-INFO "

                 Yong Cui
                 Email:  yong@csnet1.cs.tsinghua.edu.cn

                 Jiang Dong
                 Email:  dongjiang@csnet1.cs.tsinghua.edu.cn

                 Peng Wu
                 Email:  weapon@csnet1.cs.tsinghua.edu.cn

                 Mingwei Xu
                 Email:  xmw@cernet.edu.cn

                 Email comments directly to the softwire WG Mailing
                 List at softwires@ietf.org
    "

    DESCRIPTION
               "This MIB module contains managed object definitions for
                the softwire mesh framework."

    REVISION    "201302180000Z"
    DESCRIPTION
               "The MIB module is defined for management of object in
                the Softwire mesh framework."
    ::= { transmission 999 } --999 to be replaced with correct value

swmMIBObjects OBJECT IDENTIFIER ::= { swmMIB 1 }

-- swmSupportedTunnelTable
swmSupportedTunnelTable OBJECT-TYPE

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    SYNTAX      SEQUENCE OF SwmSupportedTunnelEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A table of objects that shows what kind of tunnels
        can be supported by the AFBR."
    ::= { swmMIBObjects 1 }

swmSupportedTunnelEntry  OBJECT-TYPE
    SYNTAX      SwmSupportedTunnelEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A set of objects that shows what kind of tunnels
        can be supported in the AFBR. If the AFBR supports
        multiple tunnel types, the swmSupportedTunnelTalbe
             would have several entries."
    INDEX { swmSupportedTunnelType }
    ::= { swmSupportedTunnelTable 1 }

SwmSupportedTunnelEntry ::= SEQUENCE {
    swmSupportedTunnelType              IANAtunnelType
}

swmSupportedTunnelType OBJECT-TYPE
    SYNTAX      IANAtunnelType
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "Represents the tunnel type that the AFBR support. "
    ::= { swmSupportedTunnelEntry 1 }
-- end of swmSupportedTunnelTable

--swmEncapsTable
swmEncapsTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF SwmEncapsEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A table of objects that display and control the
        softwire mesh encapsulation information."
    ::= { swmMIBObjects 2 }

swmEncapsEntry  OBJECT-TYPE
    SYNTAX      SwmEncapsEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION

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        "A table of objects that manages the softwire mesh I-IP
         encapsulation destination based on the E-IP destination prefix."
    INDEX { ifIndex,
            swmEncapsEIPDst,
            swmEncapsEIPMask
          }
    ::= { swmEncapsTable 1 }

SwmEncapsEntry ::=      SEQUENCE {
    swmEncapsEIPDst          InetAddress,
    swmEncapsEIPMask         InetAddressPrefixLength,
    swmEncapsIIPDst          InetAddress
}

swmEncapsEIPDst OBJECT-TYPE
    SYNTAX      InetAddress
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The address of the destination prefix, which is
        used for I-IP encapsulation destination lookup
        based on longest prefix match. The address type is
        opposite to tunnelIfAddressType in tunnelIfTable."
    ::= { swmEncapsEntry 1 }

swmEncapsEIPMask OBJECT-TYPE
    SYNTAX      InetAddressPrefixLength
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The prefix length of E-IP address."
    ::= { swmEncapsEntry 2 }

swmEncapsIIPDst OBJECT-TYPE
    SYNTAX      InetAddress
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The I-IP address as the encapsulated destination
         according to the E-IP address. The address type
        is the same as tunnelIfAddressType in tunnelIfTable.
        Since the tunnelIfRemoteInetAddress in tunnelIfTable
        should be 0.0.0.0 or ::, swmEncapIIPDst is the
        destination address used in the outer IP header."
    ::= { swmEncapsEntry 3 }
-- End of swmEncapsTable

-- swmBGPNeighborTable

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swmBGPNeighborTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF SwmBGPNeighborEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A table of objects that displays the softwire mesh
        BGP neighbor information."
    ::= { swmMIBObjects 3 }

swmBGPNeighborEntry  OBJECT-TYPE
    SYNTAX      SwmBGPNeighborEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A set of objects that displays the softwire mesh
        BGP neighbor information."
    INDEX {
            ifIndex,
            swmBGPNeighborInetAddress
          }
    ::= { swmBGPNeighborTable 1 }

SwmBGPNeighborEntry ::= SEQUENCE {
        swmBGPNeighborInetAddress        InetAddress,
        swmBGPNeighborTunnelType         IANAtunnelType
}

swmBGPNeighborInetAddress OBJECT-TYPE
    SYNTAX      InetAddress
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The address of the ABFR's BGP neighbor. The
        address type is the same as tunnelIfAddressType
        in tunnelIfTable"
    ::= { swmBGPNeighborEntry 1 }

swmBGPNeighborTunnelType OBJECT-TYPE
    SYNTAX      IANAtunnelType
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "Represents the type of tunnel that the
        AFBR chooses to transmit traffic with another AFBR/BGP neighbor"
    ::= { swmBGPNeighborEntry 2 }
-- End of swmBGPNeighborTable

-- conformance information

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swmMIBConformance
                    OBJECT IDENTIFIER ::= { swmMIB 2 }
swmMIBCompliances
                    OBJECT IDENTIFIER ::= { swmMIBConformance 1 }
swmMIBGroups
                    OBJECT IDENTIFIER ::= { swmMIBConformance 2 }

 -- compliance statements
swmMIBCompliance MODULE-COMPLIANCE
   STATUS current
   DESCRIPTION
       "Describes the requirements for conformance to the softwire
       mesh MIB."

   MODULE -- this module
   MANDATORY-GROUPS    {
                         swmSupportedTunnelGroup,
                         swmEncapsGroup,
                         swmBGPNeighborGroup
                       }
   ::= { swmMIBCompliances 1 }

swmSupportedTunnelGroup    OBJECT-GROUP
   OBJECTS {
       swmSupportedTunnelType
   }
   STATUS  current
   DESCRIPTION
       "The collection of objects which are used to show
       what kind of tunnel the AFBR supports."
   ::= { swmMIBGroups 1 }

swmEncapsGroup    OBJECT-GROUP
   OBJECTS {
                swmEncapsEIPDst,
        swmEncapsEIPMask,
        swmEncapsIIPDst
   }
   STATUS  current
   DESCRIPTION
       "The collection of objects which are used to display
       softwire mesh encapsulation information."
   ::= { swmMIBGroups 2 }

swmBGPNeighborGroup    OBJECT-GROUP
   OBJECTS {
        swmBGPNeighborInetAddress,
        swmBGPNeighborTunnelType

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   }
   STATUS  current
   DESCRIPTION
       "The collection of objects which are used to display
        softwire mesh BGP neighbor information."
   ::= { swmMIBGroups 3 }

END

8.  Security Considerations

   The swmMIB module can be used for configuration of certain objects,
   and anything that can be configured can be incorrectly configured,
   with potentially disastrous results.  Because this MIB module reuses
   the IP tunnel MIB, the security considerations of the IP tunnel MIB
   is also applicable to the Softwire mesh MIB.

   SNMP versions prior to SNMPv3 did not include adequate security.
   Even if the network itself is secure (for example by using IPsec),
   even then, there is no control as to who on the secure network is
   allowed to access and GET/SET (read/change/create/delete) the objects
   in this MIB module.

   It is RECOMMENDED that implementers consider the security features as
   provided by the SNMPv3 framework (see [RFC3410], section 8),
   including full support for the SNMPv3 cryptographic mechanisms (for
   authentication and privacy).

   Further, deployment of SNMP versions prior to SNMPv3 is NOT
   RECOMMENDED.  Instead, it is RECOMMENDED to deploy SNMPv3 and to
   enable cryptographic security.  It is then a customer/operator's
   responsibility to ensure that the SNMP entity giving access to an
   instance of this MIB module is properly configured to give access to
   the objects only to those principals (users) that have legitimate
   rights to indeed GET or SET (change/create/delete) them.

9.  IANA Considerations

   The MIB module in this document uses the following IANA-assigned
   OBJECT IDENTIFIER values recorded in the SMI Numbers registry, and
   the following IANA-assigned tunnelType values recorded in the
   IANAtunnelType-MIB registry:

           Descriptor        OBJECT IDENTIFIER value
           ----------        -----------------------
           swmMIB            { transmission XXX }

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          IANAtunnelType ::= TEXTUAL-CONVENTION
              SYNTAX     INTEGER {

                         softwireMesh ("XX")        -- softwire Mesh tunnel

                         }

10.  Acknowledgements

   The authors would like to thank Dave Thaler, Jean-Philippe Dionne, Qi
   Sun, Sheng Jiang, Yu Fu for their valuable comments.

11.  References

11.1.  Normative References

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

   [RFC2578]       McCloghrie, K., Ed., Perkins, D., Ed., and J.
                   Schoenwaelder, Ed., "Structure of Management
                   Information Version 2 (SMIv2)", STD 58, RFC 2578,
                   April 1999.

   [RFC2579]       McCloghrie, K., Ed., Perkins, D., Ed., and J.
                   Schoenwaelder, Ed., "Textual Conventions for SMIv2",
                   STD 58, RFC 2579, April 1999.

   [RFC2580]       McCloghrie, K., Perkins, D., and J. Schoenwaelder,
                   "Conformance Statements for SMIv2", STD 58, RFC 2580,
                   April 1999.

   [RFC4925]       Li, X., Dawkins, S., Ward, D., and A. Durand,
                   "Softwire Problem Statement", RFC 4925, July 2007.

   [RFC5512]       Mohapatra, P. and E. Rosen, "The BGP Encapsulation
                   Subsequent Address Family Identifier (SAFI) and the
                   BGP Tunnel Encapsulation Attribute", RFC 5512,
                   April 2009.

   [RFC5565]       Wu, J., Cui, Y., Metz, C., and E. Rosen, "Softwire
                   Mesh Framework", RFC 5565, June 2009.

11.2.  Informative References

   [RFC2223]       Postel, J. and J. Reynolds, "Instructions to RFC
                   Authors", RFC 2223, October 1997.

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   [RFC3410]       Case, J., Mundy, R., Partain, D., and B. Stewart,
                   "Introduction and Applicability Statements for
                   Internet-Standard Management Framework", RFC 3410,
                   December 2002.

   [RFC2629]       Rose, M., "Writing I-Ds and RFCs using XML",
                   RFC 2629, June 1999.

   [RFC4181]       Heard, C., "Guidelines for Authors and Reviewers of
                   MIB Documents", BCP 111, RFC 4181, September 2005.

11.3.  URL References

   [idguidelines]  IETF Internet Drafts editor,
                   "http://www.ietf.org/ietf/1id-guidelines.txt".

   [idnits]        IETF Internet Drafts editor,
                   "http://www.ietf.org/ID-Checklist.html".

   [xml2rfc]       XML2RFC tools and documentation,
                   "http://xml.resource.org".

   [ops]           the IETF OPS Area, "http://www.ops.ietf.org".

   [ietf]          IETF Tools Team, "http://tools.ietf.org".

Authors' Addresses

   Yong Cui
   Tsinghua University
   Department of Computer Science, Tsinghua University
   Beijing  100084
   P.R.China

   Phone: +86-10-6260-3059
   EMail: yong@csnet1.cs.tsinghua.edu.cn

   Jiang Dong
   Tsinghua University
   Department of Computer Science, Tsinghua University
   Beijing  100084
   P.R.China

   Phone: +86-10-6278-5822
   EMail: dongjiang@csnet1.cs.tsinghua.edu.cn

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   Peng Wu
   Tsinghua University
   Department of Computer Science, Tsinghua University
   Beijing  100084
   P.R.China

   Phone: +86-10-6278-5822
   EMail: weapon@csnet1.cs.tsinghua.edu.cn

   Mingwei Xu
   Tsinghua University
   Department of Computer Science, Tsinghua University
   Beijing  100084
   P.R.China

   Phone: +86-10-6278-5822
   EMail: xmw@cernet.edu.cn

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