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Internet Draft             RSTP (802.1w) MIBs             September 2004


Internet Draft                                                   V. Ngai
Expires March 2005                                    Enterasys Networks
draft-ietf-bridge-rstpmib-05.txt                                 E. Bell
                                                              3Com Corp.
                                                          September 2004

              Definitions of Managed Objects for Bridges
                   with Rapid Spanning Tree Protocol

Status of this Memo

   By submitting this Internet-Draft, I certify that any applicable
   patent or other IPR claims of which I am aware have been disclosed,
   or will be disclosed, and any of which I become aware will be
   disclosed, in accordance with RFC 3668.

   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 21, 2005.

Copyright Notice

   Copyright (C) The Internet Society (2004).  All Rights Reserved.

Abstract

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in TCP/IP based internets.
   In particular, it defines a MIB module for managing the Rapid
   Spanning Tree capability defined by the IEEE P802.1t [802.1t] and
   P802.1w [802.1w] amendments to IEEE Std 802.1D-1998 for bridging
   between Local Area Network (LAN) segments.





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   Provisions are made for support of transparent bridging.  Provisions
   are also made so that these objects apply to bridges connected by
   subnetworks other than LAN segments.  This memo also includes a MIB
   module in a manner that is compliant to SMIv2 [RFC2578].

   This memo supplements RFC 1493 [RFC1493] and RFC 2674 [RFC2674].












































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Table of Contents


   1 The Internet-Standard Management Framework ...................    4
   2 Overview .....................................................    4
   2.1 Scope ......................................................    4
   3 Structure of MIBs ............................................    4
   3.1 Structure of RSTP-MIB ......................................    5
   3.2 Relationship to Other MIBs .................................    5
   3.2.1 Relation to Original Bridge MIB ..........................    5
   3.2.1.1 The dot1dBase Group ....................................    6
   3.2.1.2 The dot1dStp Group .....................................    6
   3.2.1.3 The dot1dTp Group ......................................    7
   3.2.1.4 The dot1dStatic Group ..................................    7
   4 Definitions for RSTP-MIB .....................................    8
   5 Acknowledgments ..............................................   15
   6 Security Considerations ......................................   15
   7 Normative References .........................................   16
   8 Informative References .......................................   17
   9 Authors' Addresses ...........................................   18
    Intellectual Property Statement ...............................   19
    Disclaimer of Validity ........................................   19
    Copyright Statement ...........................................   19



























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1.  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).
   Objects in the MIB are defined using the mechanisms defined 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].


2.  Overview

   A common device present in many networks is the Bridge.  This device
   is used to connect Local Area Network segments below the network
   layer.  These devices are often known as 'layer 2 switches'.

   There are two major modes defined for this bridging: Source-Route and
   transparent.  Source-Route bridging is described by IEEE 802.5
   [802.5] and is not discussed further in this document.

   The transparent method of bridging is defined by IEEE 802.1D-1998
   [802.1D]  Managed objects for that original specification of
   transparent bridging were defined in RFC 1493 [RFC1493].


2.1.  Scope

   This MIB includes a comprehensive set of managed objects which
   attempts to match the set defined in IEEE P802.1t [802.1t] and
   P802.1w [802.1w].


3.  Structure of MIBs

   This document defines additional managed objects for Rapid Spanning
   Tree Protocol defined by IEEE P802.1t and IEEE P802.1w, on top of
   those existing in the original BRIDGE-MIB module defined in
   [RFC1493]: that MIB module is to be maintained unchanged for
   backwards compatibility.  Section 3.4.1 of the present document
   contains some recommendations regarding usage of objects in the





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   original bridge MIB by devices implementing the enhancements defined
   here.



3.1.  Structure of RSTP-MIB

   Objects in this MIB are defined as an addition to the dot1dStp group
   in the original bridge MIB [RFC1493].  The overall structure is
   shown below:

   Bridge MIB Name                       IEEE 802.1 Reference

   dot1dStp
     dot1dStpVersion                   (w) 17.16.1  ForceVersion
     dot1dStpTxHoldCount               (w) 17.16.6  TxHoldCount
     dot1dStpPathCostDefault
     dot1dStpExtPortTable
       dot1dStpPortProtocolMigration   (w) 17.18.10 mcheck
       dot1dStpPortAdminEdgePort       (t) 18.3.3   adminEdgePort
       dot1dStpPortOperEdgePort        (t) 18.3.4   operEdgePort
       dot1dStpPortAdminPointToPoint   (w) 6.4.3    adminPointToPointMAC
       dot1dStpPortOperPointToPoint    (w) 6.4.3    operPointToPointMAC
       dot1dStpPortAdminPathCost       (D) 8.5.5.3  Path Cost


3.2.  Relationship to Other MIBs

   As described above, some IEEE 802.1D management objects have not been
   included in this MIB because they overlap with objects in other MIBs
   applicable to a bridge implementing this MIB.  In particular, it is
   assumed that a bridge implementing this MIB will implement the
   original bridge MIB [RFC1493].


3.2.1.  Relation to Original Bridge MIB

   This section defines how objects in the original bridge MIB module
   [RFC1493] should be represented for devices which implement all the
   MIB modules described in this memo.  Some of the old objects are less
   useful in such devices but must still be implemented for reasons of
   backwards compatibility.








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3.2.1.1.  The dot1dBase Group

   This mandatory group contains the objects which are applicable to all
   types of bridges.  Interpretation of this group is unchanged.


3.2.1.2.  The dot1dStp Group

   This group contains the objects that denote the bridge's state with
   respect to the Spanning Tree Protocol.  If a node does not implement
   the Spanning Tree Protocol, this group will not be implemented.

   In a device supporting the Spanning Tree Algorithm and Protocol
   defined in IEEE 802.1D-1998 Clause 8, interpretation of this group is
   unchanged.

   In a device supporting the Rapid Spanning Tree Algorithm and Protocol
   defined in IEEE 802.1w Clause 17, the interpretation of objects in
   this group is unchanged except for those listed below:

   dot1dStpPriority
        Definition remains unchanged, but the permissible values are
        changed to 0-61440, in steps of 4096.

   dot1dStpPortPriority
        Definition remains unchanged, but the permissible values are
        changed to 0-240, in steps of 16.

   dot1dStpTimeSinceTopologyChange
        The time since the tcWhile timer for any port on this Bridge was
        non-zero.

   dot1dStpTopChanges
        The number of times that there have been at least one non-zero
        tcWhile timer on this Bridge.

   In a device supporting the 32-bit default Path Costs defined in IEEE
   802.1t Table 8-5, the object dot1dStpPortPathCost32 [RFC1493] should
   be used rather than the older object dot1dStpPortPathCost. The newer
   object supports the expanded range of 1-200,000,000.










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3.2.1.3.  The dot1dTp Group

   This group contains objects that describe the entity's state with
   respect to transparent bridging.  Interpretation for this group is
   unchanged.


3.2.1.4.  The dot1dStatic Group

   This group contains objects that describe the entity's state with
   respect to destination-address filtering.  Interpretation for this
   group is unchanged.






































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4.  Definitions for RSTP-MIB

RSTP-MIB DEFINITIONS ::= BEGIN

-- -------------------------------------------------------------
-- MIB for IEEE 802.1w Rapid Spanning Tree Protocol
-- -------------------------------------------------------------

IMPORTS
    MODULE-IDENTITY, OBJECT-TYPE, Integer32
        FROM SNMPv2-SMI
    TruthValue
        FROM SNMPv2-TC
    MODULE-COMPLIANCE, OBJECT-GROUP
        FROM SNMPv2-CONF
    dot1dBridge, dot1dStp, dot1dStpPortEntry
        FROM BRIDGE-MIB;

rstpMIB MODULE-IDENTITY
    LAST-UPDATED "200403210000Z"
    ORGANIZATION "IETF Bridge MIB Working Group"
    CONTACT-INFO
        "Email: Bridge-mib@ietf.org"
    DESCRIPTION
        "The Bridge MIB Extension module for managing devices
         that support the Rapid Spanning Tree Protocol defined
         by IEEE 802.1w."
    REVISION     "200403210000Z"
    DESCRIPTION
         "Draft 4"
    ::= { dot1dBridge 11 }

-- -------------------------------------------------------------
-- Addition to the dot1dStp group
-- -------------------------------------------------------------

dot1dStpVersion OBJECT-TYPE
    SYNTAX      INTEGER {
                    stpCompatible(0),
                    rstp(2)
                }
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
        "The version of Spanning Tree Protocol the bridge is
         currently running.  The value 'stpCompatible(0)'





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         indicates the Spanning Tree Protocol specified in
         IEEE 802.1D and 'rstp(2)' indicates the Rapid Spanning
         Tree Protocol specified in IEEE 802.1w.  New value may
         be defined as future versions of the protocol become
         available."
    REFERENCE
        "IEEE 802.1w clause 14.8.1, 17.12, 17.16.1"
    DEFVAL      { rstp }
    ::= { dot1dStp 16 }

dot1dStpTxHoldCount OBJECT-TYPE
    SYNTAX      Integer32 (1..10)
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
        "The value used by the Port Transmit state machine to limit
         the maximum transmission rate."
    REFERENCE
        "IEEE 802.1w clause 17.16.6"
    DEFVAL      { 3 }
    ::= { dot1dStp 17 }

dot1dStpPathCostDefault OBJECT-TYPE
    SYNTAX      INTEGER {
                    stp8021d1998(1),
                    stp8021t2001(2)
                }
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
        "The version of the Spanning Tree default Path Costs that
         are to be used by this Bridge. A value of 8021d1998(1)
         means the bridge is using the 16-bit default Path Costs from
         IEEE Std. 802.1D-1998. A value of stp8021t2001(2) means
         the bridge is using the 32-bit default Path Costs from IEEE
         Std. 802.1t."
    REFERENCE
        "IEEE 802.1D & 802.1t Table 8-5"
    ::= { dot1dStp 18 }

dot1dStpExtPortTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF Dot1dStpExtPortEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A table that contains port-specific Rapid Spanning Tree





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         information."
    ::= { dot1dStp 19 }

dot1dStpExtPortEntry OBJECT-TYPE
    SYNTAX      Dot1dStpExtPortEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A list of Rapid Spanning Tree information maintained by
         each port."
    AUGMENTS    { dot1dStpPortEntry }
    ::= { dot1dStpExtPortTable 1 }

Dot1dStpExtPortEntry ::=
    SEQUENCE {
        dot1dStpPortProtocolMigration
            TruthValue,
        dot1dStpPortAdminEdgePort
            TruthValue,
        dot1dStpPortOperEdgePort
            TruthValue,
        dot1dStpPortAdminPointToPoint
            INTEGER,
        dot1dStpPortOperPointToPoint
            TruthValue,
        dot1dStpPortAdminPathCost
            Integer32
    }

dot1dStpPortProtocolMigration OBJECT-TYPE
    SYNTAX      TruthValue
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
        "When operating in RSTP (version 2) mode, writing TRUE(1)
         to this object forces this port to transmit RSTP BPDUs.
         Any other operation on this object has no effect and
         it always returns FALSE(2) when read."
    REFERENCE
        "IEEE 802.1w clause 14.8.2.4, 17.18.10, 17.26"
    ::= { dot1dStpExtPortEntry 1 }

dot1dStpPortAdminEdgePort OBJECT-TYPE
    SYNTAX      TruthValue
    MAX-ACCESS  read-write
    STATUS      current





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    DESCRIPTION
        "The administrative value of the Edge Port parameter. A
         value of TRUE(1) indicates that this port should be
         assumed as an edge-port and a value of FALSE(2) indicates
         that this port should be assumed as a non-edge-port.
         Setting this object will also cause the corresponding
         instance of dot1dStpPortOperEdgePort to change to the
         same value. Note that even when this object's value
         is true, the value of the corresponding instance of
         dot1dStpPortOperEdgePort can be false if a BPDU has
         been received."
    REFERENCE
        "IEEE 802.1t clause 14.8.2, 18.3.3"
    ::= { dot1dStpExtPortEntry 2 }

dot1dStpPortOperEdgePort OBJECT-TYPE
    SYNTAX      TruthValue
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The operational value of the Edge Port parameter. The
         object is initialized to the value of the corresponding
         instance of dot1dStpPortAdminEdgePort. When the
         corresponding instance of dot1dStpPortAdminEdgePort is
         set, this object will be changed as well. This object
         will also be changed to FALSE on reception of a BPDU."
    REFERENCE
        "IEEE 802.1t clause 14.8.2, 18.3.4"
    ::= { dot1dStpExtPortEntry 3 }

dot1dStpPortAdminPointToPoint OBJECT-TYPE
    SYNTAX      INTEGER {
                    forceTrue(0),
                    forceFalse(1),
                    auto(2)
                }
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
        "The administrative point-to-point status of the LAN segment
         attached to this port.  A value of forceTrue(0) indicates that
         this port should always be treated as if it is connected to
         a point-to-point link.  A value of forceFalse(1) indicates
         that this port should be treated as having a shared media
         connection.  A value of auto(2) indicates that this port is
         considered to have a point-to-point link if it is an Aggregator





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         and all of its members are aggregatable, or if the MAC entity
         is configured for full duplex operation, either through
         auto-negotiation or by management means."
   REFERENCE
       "IEEE 802.1w clause 6.4.3, 6.5, 14.8.2"
   ::= { dot1dStpExtPortEntry 4 }

dot1dStpPortOperPointToPoint OBJECT-TYPE
    SYNTAX      TruthValue
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The operational point-to-point status of the LAN segment
         attached to this port.  It indicates whether a port is
         considered to have a point-to-point connection or not.
         The value is determined by management or by auto-detection,
         as described in the dot1dStpPortAdminPointToPoint object."
    REFERENCE
        "IEEE 802.1w clause 6.4.3, 6.5, 14.8.2"
    ::= { dot1dStpExtPortEntry 5 }

dot1dStpPortAdminPathCost OBJECT-TYPE
    SYNTAX      Integer32 (0..200000000)
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
        "The administratively assigned value for the contribution
         of this port to the path cost of paths towards the spanning
         tree root.

         Writing a value of '0' assigns the automatically calculated
         default Path Cost value to the port.  If the default Path
         Cost is being used, this object returns '0' when read.

         This complements the object dot1dStpPortPathCost or
         dot1dStpPortPathCost32, which returns the operational value
         of the path cost."
    REFERENCE
        "IEEE 802.1D-1998: Section 8.5.5.3"
    ::= { dot1dStpExtPortEntry 6 }

-- -------------------------------------------------------------
-- rstpMIB - Conformance Information
-- -------------------------------------------------------------

rstpConformance OBJECT IDENTIFIER ::= { rstpMIB 1 }





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rstpGroups OBJECT IDENTIFIER ::= { rstpConformance 1 }

rstpCompliances OBJECT IDENTIFIER ::= { rstpConformance 2 }

-- -------------------------------------------------------------
-- Units of conformance
-- -------------------------------------------------------------

rstpBridgeGroup OBJECT-GROUP
    OBJECTS {
        dot1dStpVersion,
        dot1dStpTxHoldCount
    }
    STATUS      current
    DESCRIPTION
        "Rapid Spanning Tree information for the bridge."
    ::= { rstpGroups 1 }

rstpDefaultPathCostGroup OBJECT-GROUP
    OBJECTS {
        dot1dStpPathCostDefault
    }
    STATUS      current
    DESCRIPTION
        "Default Spanning Tree path cost information."
    ::= { rstpGroups 2 }

rstpPortGroup OBJECT-GROUP
    OBJECTS {
        dot1dStpPortProtocolMigration,
        dot1dStpPortAdminEdgePort,
        dot1dStpPortOperEdgePort,
        dot1dStpPortAdminPointToPoint,
        dot1dStpPortOperPointToPoint,
        dot1dStpPortAdminPathCost
    }
    STATUS      current
    DESCRIPTION
        "Rapid Spanning Tree information for individual ports."
    ::= { rstpGroups 3 }

-- -------------------------------------------------------------
-- Compliance statements
-- -------------------------------------------------------------

rstpCompliance MODULE-COMPLIANCE





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    STATUS      current
    DESCRIPTION
        "The compliance statement for device support of bridging
         services."

    MODULE
        MANDATORY-GROUPS {
            rstpBridgeGroup,
            rstpPortGroup
        }

        GROUP rstpDefaultPathCostGroup
            DESCRIPTION
                "Support for this group is mandatory only if
                 both 16-bit and 32-bit Path Costs are supported."
    ::= { rstpCompliances 1 }

END
































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5.  Acknowledgments

   This document was produced on behalf of the Bridge MIB Working Group
   in the Operations and Management area of the Internet Engineering
   Task Force.

   The authors wish to thank the members of the Bridge MIB Working
   Group, especially Alex Ruzin, for their comments and suggestions
   which improved this effort.


6.  Security Considerations

   There are a number of management objects defined in this MIB that
   have a MAX-ACCESS clause of read-write and/or read-create.  Such
   objects may be considered sensitive or vulnerable in some network
   environments.  The support for SET operations in a non-secure
   environment without proper protection can have a negative effect on
   network operations.

   SNMPv1 by itself is not a secure environment.  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.

   It is recommended that the implementers consider the security
   features as provided by the SNMPv3 framework.  Specifically, the use
   of the User-based Security Model [USM] and the View-based Access
   Control Model [VACM] is recommended.





















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7.  Normative References

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

[RFC2579]    McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
             Rose, M., and S. Waldbusser, "Textual Conventions for
             SMIv2", STD 58, RFC 2579, April 1999.

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

[RFC2674]    Bell, E., Smith, A., Langille, P., Rijhsinghani, A. and
             McCloghrie, "Definitions of Managed Objects for Bridges
             with Traffic Classes, Multicast Filtering and Virtual LAN
             Extensions", RFC 2674, August 1999.

[802.1D]     "Information technology - Telecommunications and
             information exchange between systems - Local and
             metropolitan area networks - Common specifications - Part
             3: Media Access Control (MAC) Bridges:  Revision.  This is
             a revision of ISO/IEC 10038: 1993, 802.1j-1992 and 802.6k-
             1992.  It incorporates P802.11c, P802.1p and P802.12e."
             ISO/IEC 15802-3: 1998.

[RFC1493]  Decker, E., Langille, P., Rijsinghani, A. and K.  McCloghrie,
             "Definitions of Managed Objects for Bridges", RFC 1493,
             July 1993.

[802.1t]     IEEE 802.1t-2001, "(Amendment to IEEE Standard 802.1D) IEEE
             Standard for Information technology - Telecommunications
             and information exchange between systems - Local and
             metropolitan area networks - Common specifications - Part
             3: Media Access Control (MAC) Bridges: Technical and
             Editorial Corrections".

[802.1w]     IEEE 802.1w-2001, "(Amendment to IEEE Standard 802.1D) IEEE
             Standard for Information technology--Telecommunications and
             information exchange between systems--Local and
             metropolitan area networks--Common Specifications--Part 3:
             Media Access Control (MAC) Bridges: Rapid Reconfiguation".






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8.  Informative References

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













































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9.  Authors' Addresses

   Les Bell
   3Com Europe Limited
   eCom Centre, Boundary Way
   Hemel Hempstead
   Herts.  HP2 7YU
   UK

   Phone:  +44 1442 438025
   Email:  Les_Bell@3Com.com


   Vivian Ngai
   Enterasys Networks
   2691 South Decker Lake Lane
   Salt Lake City, UT 84119
   USA

   Phone: +1 801 556 5652
   Email: vivian_ngai@acm.org





























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Intellectual Property Statement

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
   made any independent effort to identify any such rights.  Information
   on the procedures with respect to rights in RFC documents can be
   found in BCP 78 and BCP 79.

   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use of
   such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at
   http://www.ietf.org/ipr.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at
   ietf-ipr@ietf.org.


Disclaimer of Validity

   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
   ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
   INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
   INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


Copyright Statement

   Copyright (C) The Internet Society (2004).  This document is subject
   to the rights, licenses and restrictions contained in BCP 78, and
   except as set forth therein, the authors retain all their rights.









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