[Docs] [txt|pdf|xml] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-renker-tsvwg-udplite-mib) 00 01 02 03 RFC 5097

Transport Area Working Group                                   G. Renker
Internet-Draft                                              G. Fairhurst
Intended status: Standards Track                  University of Aberdeen
Expires: May 1, 2008                                    October 29, 2007


                     MIB for the UDP-Lite protocol
                    draft-ietf-tsvwg-udplite-mib-03

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
   aware will be disclosed, in accordance with Section 6 of BCP 79.

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

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

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

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

   This Internet-Draft will expire on May 1, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2007).














Renker & Fairhurst         Expires May 1, 2008                  [Page 1]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


Abstract

   This document specifies a Management Information Base (MIB) module
   for the Lightweight User Datagram Protocol.  It defines a set of new
   MIB objects to characterise the behaviour and performance of
   transport layer endpoints deploying UDP-Lite.  UDP-Lite resembles
   UDP, but differs from the semantics of UDP by the addition of a
   single option.  This adds the capability for variable-length data
   checksum coverage, which can benefit a class of applications that
   prefer delivery of (partially) corrupted datagram payload data in
   preference to discarding the datagram.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Relationship to the UDP-MIB  . . . . . . . . . . . . . . .  3
     1.2.  Relationship to HOST-RESOURCES-MIB and SYSAPPL-MIB . . . .  5
     1.3.  Interpretation of the MIB Variables  . . . . . . . . . . .  5
     1.4.  Conventions  . . . . . . . . . . . . . . . . . . . . . . .  8
   2.  The Internet-Standard Management Framework . . . . . . . . . .  9
   3.  Definitions  . . . . . . . . . . . . . . . . . . . . . . . . . 10
   4.  Security Considerations  . . . . . . . . . . . . . . . . . . . 23
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 25
   6.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 27
   7.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 32
     7.1.  Normative References . . . . . . . . . . . . . . . . . . . 32
     7.2.  Informative References . . . . . . . . . . . . . . . . . . 32
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 34
   Intellectual Property and Copyright Statements . . . . . . . . . . 35





















Renker & Fairhurst         Expires May 1, 2008                  [Page 2]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


1.  Introduction

   The Lightweight User Datagram Protocol (UDP-Lite) [RFC3828] (also
   known as UDPLite) is an IETF standards-track transport protocol.  The
   operation of UDP-Lite is similar to the User Datagram Protocol (UDP)
   [RFC0768], but can also serve applications in error-prone network
   environments that prefer to have partially damaged payloads delivered
   rather than discarded.  This is achieved by changing the semantics of
   the UDP Length field to that of a Checksum Coverage field.  If this
   feature is not used, UDP-Lite is semantically identical to UDP.

   The interface of UDP-Lite differs from that of UDP by the addition of
   a single option, which communicates a length value.  At the sender
   this specifies the intended datagram checksum coverage; at the
   receiver it signifies a minimum coverage threshold for incoming
   datagrams.  This length value may also be modified during the
   lifetime of a connection.  UDP-Lite does not provide mechanisms to
   negotiate the checksum coverage between the sender and receiver.
   Where required, this needs to be communicated by another protocol.
   DCCP [RFC4340] for instance includes a capability to negotiate
   checksum coverage values.

   This document defines a set of runtime statistics (variables) that
   facilitate both network management/monitoring as well as unified
   comparisons between different protocol implementations and operating
   environments.  To provide a common interface for users and
   implementors of UDP-Lite modules, the definitions of these runtime
   statistics are provided as a MIB module using the SMIv2 format
   [RFC2578].

1.1.  Relationship to the UDP-MIB

   The similarities between UDP and UDP-Lite suggest that the MIB module
   for UDP-Lite should resemble that of UDP [RFC4113], with extensions
   corresponding to the additional capabilities of UDP-Lite.  The UDP-
   Lite MIB module is placed beneath the mib-2 subtree, adhering to the
   familiar structure of the UDP-MIB module to ease integration.

   In particular, these well-known basic counters are supported:

   o  InDatagrams

   o  NoPorts

   o  InErrors

   o  OutDatagrams




Renker & Fairhurst         Expires May 1, 2008                  [Page 3]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   The following read-only variables have been added to the basic
   structure used in the UDP-MIB module:

      InPartialCov: The number of received datagrams, with a valid
      format and checksum, whose checksum coverage is strictly less than
      the datagram length.

      InBadChecksum: The number of received datagrams with an invalid
      checksum (i.e. where the receiver-recalculated UDP-Lite checksum
      does not match that in the Checksum field).  Unlike NoPorts, this
      error type also counts as InErrors.

      OutPartialCov: The number of sent datagrams with a valid format
      and checksum whose checksum coverage is strictly less than the
      datagram length.

   All non-error counters used in this document are 64-bit counters.
   This is a departure from UDP, which traditionally used 32-bit
   counters and mandates 64-bit counters only on fast networks
   [RFC4113].  This choice is justified by the fact that UDP-Lite is a
   more recent protocol, and that network speeds continue to grow.

   Another difference from the UDP MIB module is that the UDP-Lite MIB
   module does not support an IPv4-only listener table.  This feature
   was present only for compatibility reasons and is superseded by the
   more informative endpoint table.  Two columnar objects have been
   added to this table:

      udpliteEndpointMinCoverage: The minimum acceptable receiver
      checksum coverage length [RFC3828].  This value may be manipulated
      by the application attached to the receiving endpoint.

      udpliteEndpointViolCoverage: This object is optional and counts
      the number of valid datagrams with a checksum coverage value less
      than the corresponding value of udpliteEndpointMinCoverage.
      Although being otherwise valid, such datagrams are discarded
      rather than passed to the application.  This object thus serves to
      separate cases of violated coverage from other InErrors.

   The second entry is not required to manage the transport protocol and
   hence is not mandatory.  It may be implemented to assist in debugging
   application design and configuration.

   The UDP-Lite MIB module also provides a discontinuity object to help
   determine whether one or more of its counters experienced a
   discontinuity event.  This is an event, other than re-initialising
   the management system, which invalidates the management entity's
   understanding of the counter values.



Renker & Fairhurst         Expires May 1, 2008                  [Page 4]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   For example, if UDP-Lite is implemented as a loadable operating
   system module, a module load or unload would produce a discontinuity.
   By querying the value of udpliteStatsDiscontinuityTime, a management
   entity can determine whether or not a discontinuity event has
   occurred.

1.2.  Relationship to HOST-RESOURCES-MIB and SYSAPPL-MIB

   The UDP-Lite endpoint table contains one columnar object,
   udpliteEndpointProcess, reporting a unique value which identifies a
   distinct piece of software associated with this endpoint.  (When more
   than one piece of software is associated with this endpoint, a
   representative is chosen; so that consecutive queries consistently
   refer to the same identifier, as long as the representative piece of
   software is running and still associated with the endpoint.)

   The value of udpliteEndpointProcess is reported as an Unsigned32; and
   it shares with the hrSWRunIndex of the HOST-RESOURCES-MIB [RFC2790]
   and the sysApplElmtRunIndex of the SYSAPPL-MIB [RFC2287] the
   requirement that, wherever possible, this should be the native and
   unique identification number employed by the system.

   If the SYSAPPL-MIB module is available, the value of
   udpliteEndpointProcess should correspond to the appropriate value of
   sysApplElmtRunIndex.  If not available, an alternative should be used
   (e.g. the hrSWRunIndex of the HOST-RESOURCES-MIB module).

1.3.  Interpretation of the MIB Variables

   Figure 1 shows an informal survey of the packet processing path, with
   reference to counter names in brackets.




















Renker & Fairhurst         Expires May 1, 2008                  [Page 5]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   Received UDP-Lite Datagrams
     |
     |                +- Full Coverage ---------------------+-> Deliver
     |                |                                     |
     +- Valid Header--+               +- >= Rec. Coverage --+
     | (InDatagrams)  |               |
     |                +- Partial -----+
     |                (InPartialCov)  |
     |                                +-  < Rec. Coverage --+
     |                               (EndpointViolCoverage) |
     |                                                      |
     |                                                      |
     +- Header Error ---+                                   |
     |                  |                                   |
     +- Checksum Error -+-----------------------------------+-> Discard
     |  (InBadChecksum)                                       (InErrors)
     |
     +- Port Error -------------------------------------------> Discard
        (NoPorts)

                 Figure 1: UDP-Lite Input Processing Path

   A platform-independent test of the UDP-Lite implementations in two
   connected end hosts may be performed as follows.

   On the sending side, OutDatagrams and OutPartialCov are observed.
   The ratio OutPartialCov/OutDatagrams describes the fraction (between
   0 and 1) of datagrams using partial checksum coverage.

   On the receiving side, InDatagrams, InPartialCov, and InErrors are
   monitored.  If datagrams are received from the given sender, InErrors
   is close to zero, and InPartialCov is zero, no partial coverage is
   employed.  If no datagrams are received and InErrors increases
   proportionally with the sending rate, a configuration error is likely
   (a wrong value of receiver minimum checksum coverage).

   The InBadChecksum counter reflects errors that may persist following
   end-host processing, router processing, or link processing (this
   includes illegal coverage values as defined in [RFC3828], since
   checksum and checksum coverage are mutually inter-dependent).  In
   particular, InBadChecksum can serve as an indicator of the residual
   link bit error rate: on links with higher bit error rates, a lower
   value of the checksum coverage may help to reduce both the values of
   InErrors and InBadChecksum.

   By observing these values and adapting the configuration, a setting
   may then be found that is more adapted to the specific type of link,
   as well as the type of payload; indicated by a reduction of the



Renker & Fairhurst         Expires May 1, 2008                  [Page 6]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   number of discarded datagrams (InErrors), leading to an improved
   performance.

   The above statistics are elementary and can be used to derive the
   following information:

   o  The total number of incoming datagrams is InDatagrams + InErrors +
      NoPorts

   o  The number of InErrors that were discarded due to problems other
      than bad checksum is InErrors - InBadChecksum

   o  The number of InDatagrams that have full coverage is InDatagrams -
      InPartialCov.

   o  The number of OutDatagrams that have full coverage is OutDatagrams
      - OutPartialCov.

   The following Case diagram [CASE] summarises the relationships
   between the counters on the input processing path.

          Transport Layer Interface
   -------------------------------------------------------------
                     /\
                     ||
                  ----------------------------- InDatagrams
                     ||                             ^
                     ||                             |
                     ||                             |
                     ||----------------------> InPartialCov
                     ||                             |
                     ||                             |
                     ||                             v
                     ||                     EndpointViolCoverage
                     ||                             |
    NoPorts <--------||                             |
                     ||                             |
                     ||------> InBadChecksum ------>|
                     ||                             |
                     ||                             |
                     ||                             v
                     ||------------------------> InErrors
                     ||
                     ||
   -------------------------------------------------------------
           Network Layer Interface

            Figure 2: Counters for received UDP-Lite Datagrams



Renker & Fairhurst         Expires May 1, 2008                  [Page 7]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   A configuration error may occur when a sender chooses a coverage
   value for the datagrams that it sends that is less than the minimum
   coverage configured by the intended recipient.  The minimum coverage
   is set on a per-session basis by the application associated with the
   listening endpoint, and its current value is recorded in the
   udpliteEndpointTable.  Reception of valid datagrams with a checksum
   coverage value less than this threshold results in dropping the
   datagram [RFC3828] and incrementing InErrors.  To improve debugging
   of such (misconfigured) cases, an implementer may choose to support
   the optional udpliteEndpointViolCoverage entry in the endpoint table
   (Section 1.1.) that specifically counts datagrams falling in this
   category.  Without this feature, failure due to misconfiguration can
   not be distinguished from datagram processing failure.

1.4.  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 BCP 14, [RFC2119].
































Renker & Fairhurst         Expires May 1, 2008                  [Page 8]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


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).
   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].





































Renker & Fairhurst         Expires May 1, 2008                  [Page 9]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


3.  Definitions

   UDPLITE-MIB DEFINITIONS ::= BEGIN

   IMPORTS
       MODULE-IDENTITY,
       OBJECT-TYPE,
       mib-2, Unsigned32,
       Counter32, Counter64   FROM SNMPv2-SMI           -- [RFC2578]

       TimeStamp              FROM SNMPv2-TC            -- [RFC2579]

       MODULE-COMPLIANCE,
       OBJECT-GROUP           FROM SNMPv2-CONF          -- [RFC2580]

       InetAddress,
       InetAddressType,
       InetPortNumber         FROM INET-ADDRESS-MIB;    -- [RFC4001]

































Renker & Fairhurst         Expires May 1, 2008                 [Page 10]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   udpliteMIB MODULE-IDENTITY
       LAST-UPDATED "200710290000Z"       -- Mon, 29th Oct 2007
       ORGANIZATION "IETF TSV Working Group (TSVWG)"
       CONTACT-INFO
              "IETF TSV Working Group
               http://www.ietf.org/html.charters/tsvwg-charter.html
               Mailing List: tsvwg@ietf.org

               Gerrit Renker, Godred Fairhurst
               Electronics Research Group
               School of Engineering, University of Aberdeen
               Fraser Noble Building, Aberdeen AB24 3UE, UK"
       DESCRIPTION
              "The MIB module for managing UDP-Lite implementations.
               Copyright (C) The IETF Trust (2007). This version of
               this MIB module is part of RFC ZZZ; see the RFC
               itself for full legal notices."

       -- RFC Ed.: replace ZZZ with actual RFC number & remove this note

       REVISION "200710290000Z"           -- Mon, 29th Oct 2007
       DESCRIPTION
              "Initial SMIv2 revision, based on the format of the UDP
               MIB module (RFC 4113) and published as RFC ZZZ."

       -- RFC Ed.: replace ZZZ with actual RFC number & remove this note

       ::= { mib-2 XXX }

       -- RFC Ed.: replace XXX with OBJECT-IDENTIFIER & remove this note


   udplite      OBJECT IDENTIFIER ::= { udpliteMIB 1 }


   udpliteInDatagrams OBJECT-TYPE         -- as in UDP-MIB
       SYNTAX     Counter64
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The total number of UDP-Lite datagrams that were
               delivered to UDP-Lite users.
               Discontinuities in the value of this counter can occur
               at re-initialisation of the management system, and at
               other times as indicated by the value of
               udpliteStatsDiscontinuityTime."
       ::= { udplite 1 }




Renker & Fairhurst         Expires May 1, 2008                 [Page 11]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   udpliteInPartialCov OBJECT-TYPE        -- new in UDP-Lite
       SYNTAX     Counter64
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The total number of UDP-Lite datagrams that were
               delivered to UDP-Lite users (applications) and whose
               checksum coverage was strictly less than the datagram
               length.
               Discontinuities in the value of this counter can occur
               at re-initialisation of the management system, and at
               other times as indicated by the value of
               udpliteStatsDiscontinuityTime."
       ::= { udplite 2 }


   udpliteNoPorts OBJECT-TYPE             -- as in UDP-MIB
       SYNTAX     Counter32
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The total number of received UDP-Lite datagrams for
               which there was no listener at the destination port.

               Discontinuities in the value of this counter can occur
               at re-initialisation of the management system, and at
               other times as indicated by the value of
               udpliteStatsDiscontinuityTime."
       ::= { udplite 3 }


   udpliteInErrors OBJECT-TYPE            -- as in UDP-MIB
       SYNTAX     Counter32
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The number of received UDP-Lite datagrams that could not
               be delivered for reasons other than the lack of an
               application at the destination port.
               Discontinuities in the value of this counter can occur
               at re-initialisation of the management system, and at
               other times as indicated by the value of
               udpliteStatsDiscontinuityTime."
       ::= { udplite 4 }







Renker & Fairhurst         Expires May 1, 2008                 [Page 12]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   udpliteInBadChecksum OBJECT-TYPE       -- new in UDP-Lite
       SYNTAX     Counter32
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The number of received UDP-Lite datagrams whose checksum
               could not be validated. This includes illegal checksum
               coverage values, as their use would lead to incorrect
               checksums.
               Discontinuities in the value of this counter can occur
               at re-initialisation of the management system, and at
               other times as indicated by the value of
               udpliteStatsDiscontinuityTime."
       REFERENCE "RFC 3828, section 3.1"
       ::= { udplite 5 }


   udpliteOutDatagrams OBJECT-TYPE        -- as in UDP-MIB
       SYNTAX     Counter64
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The total number of UDP-Lite datagrams sent from this
               entity.
               Discontinuities in the value of this counter can occur
               at re-initialisation of the management system, and at
               other times as indicated by the value of
               udpliteStatsDiscontinuityTime."
       ::= { udplite 6 }


   udpliteOutPartialCov OBJECT-TYPE       -- new in UDP-Lite
       SYNTAX     Counter64
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The total number of udpliteOutDatagrams whose
               checksum coverage was strictly less than the
               datagram length.
               Discontinuities in the value of this counter can occur
               at re-initialisation of the management system, and at
               other times as indicated by the value of
               udpliteStatsDiscontinuityTime."
       ::= { udplite 7 }


   udpliteEndpointTable OBJECT-TYPE
       SYNTAX     SEQUENCE OF UdpLiteEndpointEntry



Renker & Fairhurst         Expires May 1, 2008                 [Page 13]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


       MAX-ACCESS not-accessible
       STATUS     current
       DESCRIPTION
              "A table containing information about this entity's
               UDP-Lite endpoints on which a local application is
               currently accepting or sending datagrams.

               The address type in this table represents the address
               type used for the communication, irrespective of the
               higher-layer abstraction.  For example, an application
               using IPv6 'sockets' to communicate via IPv4 between
               ::ffff:10.0.0.1 and ::ffff:10.0.0.2 would use
               InetAddressType ipv4(1).

               Like the udpTable in RFC 4113, this table also allows
               the representation of an application that completely
               specifies both local and remote addresses and ports. A
               listening application is represented in three possible
               ways:

               1) An application that is willing to accept both IPv4
                  and IPv6 datagrams is represented by a
                  udpliteEndpointLocalAddressType of unknown(0) and a
                  udpliteEndpointLocalAddress of ''h (a zero-length
                  octet-string).

               2) An application that is willing to accept only IPv4
                  or only IPv6 datagrams is represented by a
                  udpliteEndpointLocalAddressType of the appropriate
                  address type and a udpliteEndpointLocalAddress of
                  '0.0.0.0' or '::' respectively.

               3) An application that is listening for datagrams only
                  for a specific IP address but from any remote
                  system is represented by a
                  udpliteEndpointLocalAddressType of the appropriate
                  address type, with udpliteEndpointLocalAddress
                  specifying the local address.

               In all cases where the remote address is a wildcard,
               the udpliteEndpointRemoteAddressType is unknown(0),
               the udpliteEndpointRemoteAddress is ''h (a zero-length
               octet-string), and the udpliteEndpointRemotePort is 0.

               If the operating system is demultiplexing UDP-Lite
               packets by remote address/port, or if the application
               has 'connected' the socket specifying a default remote
               address/port, the udpliteEndpointRemote* values should



Renker & Fairhurst         Expires May 1, 2008                 [Page 14]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


               be used to reflect this."
       ::= { udplite 8 }


   udpliteEndpointEntry OBJECT-TYPE
       SYNTAX     UdpLiteEndpointEntry
       MAX-ACCESS not-accessible
       STATUS     current
       DESCRIPTION
              "Information about a particular current UDP-Lite endpoint.

               Implementers need to pay attention to the sizes of
               udpliteEndpointLocalAddress/RemoteAddress, as OIDs of
               column instances in this table must have no more than
               128 sub-identifiers in order to remain accessible with
               SNMPv1, SNMPv2c, and SNMPv3."
       INDEX   { udpliteEndpointLocalAddressType,
                 udpliteEndpointLocalAddress,
                 udpliteEndpointLocalPort,
                 udpliteEndpointRemoteAddressType,
                 udpliteEndpointRemoteAddress,
                 udpliteEndpointRemotePort,
                 udpliteEndpointInstance }
       ::= { udpliteEndpointTable 1 }


   UdpLiteEndpointEntry ::= SEQUENCE {
           udpliteEndpointLocalAddressType   InetAddressType,
           udpliteEndpointLocalAddress       InetAddress,
           udpliteEndpointLocalPort          InetPortNumber,
           udpliteEndpointRemoteAddressType  InetAddressType,
           udpliteEndpointRemoteAddress      InetAddress,
           udpliteEndpointRemotePort         InetPortNumber,
           udpliteEndpointInstance           Unsigned32,
           udpliteEndpointProcess            Unsigned32,
           udpliteEndpointMinCoverage        Unsigned32,
           udpliteEndpointViolCoverage       Counter32
   }













Renker & Fairhurst         Expires May 1, 2008                 [Page 15]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   udpliteEndpointLocalAddressType OBJECT-TYPE
       SYNTAX     InetAddressType
       MAX-ACCESS not-accessible
       STATUS     current
       DESCRIPTION
              "The address type of udpliteEndpointLocalAddress.  Only
               IPv4, IPv4z, IPv6, and IPv6z addresses are expected, or
               unknown(0) if datagrams for all local IP addresses are
               accepted."
       ::= { udpliteEndpointEntry 1 }









































Renker & Fairhurst         Expires May 1, 2008                 [Page 16]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   udpliteEndpointLocalAddress OBJECT-TYPE
       SYNTAX     InetAddress
       MAX-ACCESS not-accessible
       STATUS     current
       DESCRIPTION
              "The local IP address for this UDP-Lite endpoint.

               The value of this object can be represented in three
               possible ways, depending on the characteristics of the
               listening application:

               1. For an application that is willing to accept both
                  IPv4 and IPv6 datagrams, the value of this object
                  must be ''h (a zero-length octet-string), with
                  the value of the corresponding instance of the
                  EndpointLocalAddressType object being unknown(0).

               2. For an application that is willing to accept only
                  IPv4 or only IPv6 datagrams, the value of this
                  object must be '0.0.0.0' or '::', respectively,
                  while the corresponding instance of the
                  EndpointLocalAddressType object represents the
                  appropriate address type.

               3. For an application that is listening for data
                  destined only to a specific IP address, the value
                  of this object is the specific IP address for
                  which this node is receiving packets, with the
                  corresponding instance of the
                  EndpointLocalAddressType object representing the
                  appropriate address type.

               As this object is used in the index for the
               udpliteEndpointTable, implementors should be careful
               not to create entries that would result in OIDs with
               more than 128 sub-identifiers; this is because of SNMP
               and SMI limitations."
       ::= { udpliteEndpointEntry 2 }


   udpliteEndpointLocalPort OBJECT-TYPE
       SYNTAX     InetPortNumber
       MAX-ACCESS not-accessible
       STATUS     current
       DESCRIPTION
              "The local port number for this UDP-Lite endpoint."
       ::= { udpliteEndpointEntry 3 }




Renker & Fairhurst         Expires May 1, 2008                 [Page 17]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   udpliteEndpointRemoteAddressType OBJECT-TYPE
       SYNTAX     InetAddressType
       MAX-ACCESS not-accessible
       STATUS     current
       DESCRIPTION
              "The address type of udpliteEndpointRemoteAddress.  Only
               IPv4, IPv4z, IPv6, and IPv6z addresses are expected, or
               unknown(0) if datagrams for all remote IP addresses are
               accepted.  Also, note that some combinations of
               udpliteEndpointLocalAdressType and
               udpliteEndpointRemoteAddressType are not supported.  In
               particular, if the value of this object is not
               unknown(0), it is expected to always refer to the
               same IP version as udpliteEndpointLocalAddressType."
       ::= { udpliteEndpointEntry 4 }


   udpliteEndpointRemoteAddress OBJECT-TYPE
       SYNTAX     InetAddress
       MAX-ACCESS not-accessible
       STATUS     current
       DESCRIPTION
              "The remote IP address for this UDP-Lite endpoint.  If
               datagrams from any remote system are to be accepted,
               this value is ''h (a zero-length octet-string).
               Otherwise, it has the type described by
               udpliteEndpointRemoteAddressType and is the address of
               the remote system from which datagrams are to be
               accepted (or to which all datagrams will be sent).

               As this object is used in the index for the
               udpliteEndpointTable, implementors should be careful
               not to create entries that would result in OIDs with
               more than 128 sub-identifiers; this is because of SNMP
               and SMI limitations."
       ::= { udpliteEndpointEntry 5 }


   udpliteEndpointRemotePort OBJECT-TYPE
       SYNTAX     InetPortNumber
       MAX-ACCESS not-accessible
       STATUS     current
       DESCRIPTION
              "The remote port number for this UDP-Lite endpoint. If
               datagrams from any remote system are to be accepted,
               this value is zero."
       ::= { udpliteEndpointEntry 6 }




Renker & Fairhurst         Expires May 1, 2008                 [Page 18]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   udpliteEndpointInstance OBJECT-TYPE
       SYNTAX     Unsigned32 (1..'ffffffff'h)
       MAX-ACCESS not-accessible
       STATUS     current
       DESCRIPTION
              "The instance of this tuple. This object is used to
               distinguish among multiple processes 'connected' to
               the same UDP-Lite endpoint. For example, on a system
               implementing the BSD sockets interface, this would be
               used to support the SO_REUSEADDR and SO_REUSEPORT
               socket options."
       ::= { udpliteEndpointEntry 7 }


   udpliteEndpointProcess OBJECT-TYPE
       SYNTAX     Unsigned32
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "A unique value corresponding to a piece of software
               running on this endpoint.

               If this endpoint is associated with more than one piece
               of software, the agent should choose one of these; such
               that subsequent reads will consistently return the same
               value, as long as the representative piece of software
               is running and still associated with the endpoint. The
               implementation may use any algorithm satisfying these
               constraints (e.g. choosing the entity with the oldest
               start time).

               This identifier is platform-specific. Wherever possible,
               it should use the system's native, unique identification
               number as value.

               If the SYSAPPL-MIB module is available, the value should
               be the same as sysApplElmtRunIndex. If not available, an
               alternative should be used (e.g. the hrSWRunIndex of the
               HOST-RESOURCES-MIB module).

               If it is not possible to uniquely identify the pieces of
               software associated with this endpoint, then the value
               zero should be used. (Note that zero is otherwise a
               valid value for sysApplElmtRunIndex.)"
       ::= { udpliteEndpointEntry 8 }






Renker & Fairhurst         Expires May 1, 2008                 [Page 19]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   udpliteEndpointMinCoverage OBJECT-TYPE -- new in UDP-Lite
       SYNTAX     Unsigned32
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The minimum checksum coverage expected by this endpoint.
               A value of 0 indicates that only fully covered datagrams
               are accepted."
       REFERENCE "RFC 3828, section 3.1"
       ::= { udpliteEndpointEntry 9 }


   udpliteEndpointViolCoverage OBJECT-TYPE -- new / optional in UDP-Lite
       SYNTAX     Counter32
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The number of datagrams received by this endpoint whose
               checksum coverage violated the minimum coverage threshold
               set for this connection (i.e. all valid datagrams whose
               checksum coverage was strictly smaller than the minimum,
               as defined in RFC 3828).
               Discontinuities in the value of this counter can occur
               at re-initialisation of the management system, and at
               other times as indicated by the value of
               udpliteStatsDiscontinuityTime."
       ::= { udpliteEndpointEntry 10 }


   udpliteStatsDiscontinuityTime OBJECT-TYPE
       SYNTAX     TimeStamp
       MAX-ACCESS read-only
       STATUS     current
       DESCRIPTION
              "The value of sysUpTime at the most recent occasion at
               which one or more of the UDP-Lite counters suffered a
               discontinuity.
               A value of zero indicates no such discontinuity has
               occurred since the last re-initialisation of the local
               management subsystem."
       ::= { udplite 9 }


   -- Conformance Information

   udpliteMIBConformance OBJECT IDENTIFIER ::= { udpliteMIB 2 }

   udpliteMIBCompliance MODULE-COMPLIANCE



Renker & Fairhurst         Expires May 1, 2008                 [Page 20]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


       STATUS     current
       DESCRIPTION
              "The compliance statement for systems that implement
               UDP-Lite.

               There are a number of INDEX objects that cannot be
               represented in the form of OBJECT clauses in SMIv2,
               but for which we have the following compliance
               requirements, expressed in OBJECT clause form in this
               description clause:

               -- OBJECT      udpliteEndpointLocalAddressType
               -- SYNTAX      InetAddressType { unknown(0), ipv4(1),
               --                               ipv6(2), ipv4z(3),
               --                               ipv6z(4) }
               -- DESCRIPTION
               --     Support for dns(16) is not required.
               -- OBJECT      udpliteEndpointLocalAddress



               -- SYNTAX      InetAddress (SIZE(0|4|8|16|20))
               -- DESCRIPTION
               --     Support is only required for zero-length
               --     octet-strings, and for scoped and unscoped
               --     IPv4 and IPv6 addresses.
               -- OBJECT      udpliteEndpointRemoteAddressType
               -- SYNTAX      InetAddressType { unknown(0), ipv4(1),
               --                               ipv6(2), ipv4z(3),
               --                               ipv6z(4) }
               -- DESCRIPTION
               --     Support for dns(16) is not required.
               -- OBJECT      udpliteEndpointRemoteAddress
               -- SYNTAX      InetAddress (SIZE(0|4|8|16|20))
               -- DESCRIPTION
               --     Support is only required for zero-length
               --     octet-strings, and for scoped and unscoped
               --     IPv4 and IPv6 addresses.
              "
       MODULE  -- this module
            MANDATORY-GROUPS { udpliteBaseGroup,
                               udplitePartialCsumGroup,
                               udpliteEndpointGroup    }
        GROUP               udpliteAppGroup
        DESCRIPTION
               "This group is optional and provides supplementary
                information about the effectiveness of using minimum
                checksum coverage thresholds on endpoints."



Renker & Fairhurst         Expires May 1, 2008                 [Page 21]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


       ::= { udpliteMIBConformance 1 }


   udpliteMIBGroups OBJECT IDENTIFIER ::= { udpliteMIBConformance 2 }


   udpliteBaseGroup OBJECT-GROUP          -- as in UDP
       OBJECTS   { udpliteInDatagrams, udpliteNoPorts, udpliteInErrors,
                   udpliteOutDatagrams, udpliteStatsDiscontinuityTime }
       STATUS     current
       DESCRIPTION
              "The group of objects providing for counters of
               basic UDP-like statistics."
       ::= { udpliteMIBGroups 1 }


   udplitePartialCsumGroup OBJECT-GROUP  -- specific to UDP-Lite
   OBJECTS   { udpliteInPartialCov,
               udpliteInBadChecksum,
               udpliteOutPartialCov  }
       STATUS     current
       DESCRIPTION
              "The group of objects providing for counters of
               transport-layer statistics exclusive to UDP-Lite."
       ::= { udpliteMIBGroups 2 }


   udpliteEndpointGroup OBJECT-GROUP
       OBJECTS    { udpliteEndpointProcess, udpliteEndpointMinCoverage }
       STATUS     current
       DESCRIPTION
              "The group of objects providing for the IP version
               independent management of UDP-Lite 'endpoints'."
       ::= { udpliteMIBGroups 3 }


   udpliteAppGroup OBJECT-GROUP
       OBJECTS    { udpliteEndpointViolCoverage }
       STATUS     current
       DESCRIPTION
              "The group of objects that provide application-level
               information for the configuration management of
               UDP-Lite 'endpoints'."
       ::= { udpliteMIBGroups 4 }

   END





Renker & Fairhurst         Expires May 1, 2008                 [Page 22]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


4.  Security Considerations

   There are no management objects defined in this MIB module that have
   a MAX-ACCESS clause of read-write and/or read-create.  So, if this
   MIB module is implemented correctly, then there is no risk that an
   intruder can alter or create any management objects of this MIB
   module via direct SNMP SET operations.

   Some of the readable objects in this MIB module (i.e., objects with a
   MAX-ACCESS other than not-accessible) may be considered sensitive or
   vulnerable in some network environments.  It is thus important to
   control even GET and/or NOTIFY access to these objects and possibly
   to even encrypt the values of these objects when sending them over
   the network via SNMP.  These are the tables and objects and their
   sensitivity/vulnerability:

   Since UDP-Lite permits the delivery of (partially) corrupted data to
   an end host, the counters defined in this MIB module may be used to
   infer information about the characteristics of the end-to-end path
   over which the datagrams are communicated.

   The indices of the udpliteEndpointTable contain information about the
   listeners on an entity.  In particular, the udpliteEndpointLocalPort
   and udpliteLocalPort objects in the indices can be used to identify
   what ports are open on the machine and which attacks are likely to
   succeed, without the attacker having to run a port scanner.  The
   table also identifies the currently listening UDP-Lite ports.  This
   could be used to infer the type of application associated with the
   port at the receiver.  The udpliteEndpointMinCoverage provides
   information about the requirements of the transport service
   associated with a specific UDP-Lite port.  This provides additional
   detail concerning the type of application associated with the port at
   the receiver.

   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 RFC 3410 [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



Renker & Fairhurst         Expires May 1, 2008                 [Page 23]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   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.















































Renker & Fairhurst         Expires May 1, 2008                 [Page 24]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


5.  IANA Considerations

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

                 +------------+-------------------------+
                 | Descriptor | OBJECT IDENTIFIER value |
                 +------------+-------------------------+
                 | udpliteMIB |      { mib-2 XXX }      |
                 +------------+-------------------------+









































Renker & Fairhurst         Expires May 1, 2008                 [Page 25]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


==> Note to the RFC Editor (to be removed prior to publication):

   The IANA is requested to assign a value for "XXX" under the 'mib-2'
   subtree and to record the assignment in the SMI Numbers registry.
   When the assignment has been made, the RFC Editor is asked to replace
   "XXX" (here and in the MIB module) with the assigned value and to
   remove this note.












































Renker & Fairhurst         Expires May 1, 2008                 [Page 26]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


6.  Acknowledgments

   The design of the MIB module presented in this document owes much to
   the format of the module presented in [RFC4113].















































Renker & Fairhurst         Expires May 1, 2008                 [Page 27]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


==> NOTE TO THE RFC EDITOR: PLEASE REMOVE THIS LOG PRIOR TO PUBLICATION

   Revision 00 of draft-ietf-tsvwg-udplite-mib was obsoleted by revision
   01 due to a syntax error (quote transposed with full-stop) in the MIB
   module, which is corrected in rev-01.  Thanks to Magnus Westerlund
   for identifying this.

   Draft draft-ietf-tsvwg-udplite-mib-00 was published as a work item of
   tsvwg, June 2007.

   The following changelog lists the changes up to revision 02 (which
   became rev-00/01 of this document) of the preceding individual draft
   submission draft-renker-tsvwg-udplite-mib.

   Changes introduced in rev-01:

   o  General:

         - incremented revision number to 01

         - updated date to November

         - rephrased abstract

   o  Section 1:

         - rephrased the beginning of the second paragraph

   o  Section 1.1:

         - rephrased some items

         - added missing InBadChecksum heading

         - updated text to refer to 64bit counters

   o  Section 1.3:

         - removed 'x' in 'datagrams'

         - rephrased for clarity

         - Figure 1: missing bracketed text should be InErrors

         - Figure 1: correction - NoPorts are not counted as InDatagrams






Renker & Fairhurst         Expires May 1, 2008                 [Page 28]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   o  Section 2:

         - made the "Editor's Note" stand out more

   o  Section 3 / MIB:

         - upgraded 11 32bit counters to 64bit

         - moved from experimental to mib-2

         - updated revision date

   o  Section 4:

         - some minor changes

   o  Section 5:

         - again highlighted the Editor's Note by using `==>' to make it
         consistent

   Changes introduced in rev-02:

   o  General:

         - updated month, date, and revision

         - changed `transport layer entities' to `endpoints' in abstract

   o  Section 1:

         - added missing comma after `option'

         - split explanatory clause after colon into standalone clause

   o  Section 1.1:

         - added a bullet list of standard counters known from the UDP
         MIB

         - added a note that NoPorts does not increment InErrors

         - removed description of InBadCoverage (no longer in MIB, see
         below)

         - qualified note with on 64-bit counters wrt `non-error'
         counters, reflecting the change that all error counters have
         been changed to Counter32



Renker & Fairhurst         Expires May 1, 2008                 [Page 29]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


         - Nit: changed `fairly recent' -> `more recent'

         - removed traces of InBadCoverage (see below)

   o  Section 1.3:

         - corrected figure 1 (NoPorts was inconsistent with text; Rec
         Coverage was incorrectly labelled, it didn't show
         EndpointViolCoverage; slight reformatting)

         - Nit: `wrong value' -> `a wrong value'

         - clarified that InBadChecksum can also serve as indicator of
         path bit error rate

         - Nit: `which' -> `that' in `a setting may then ...' and `A
         configuration error may ...'

         - removed traces of InBadCoverage (see below)

   o  Section 3 (the MIB):

         - updated LAST-UPDATED and REVISION to match the revision date

         - updated the Copyright in DESCRIPTION from 2006 to 2007

         - converted all error counters to Counter32, following IETF
         input for rev-01

         - added a required IMPORTS statement for Counter32 to UDPLITE-
         MIB DEFINITIONS

         - demoted the following error counters from Counter64 to
         Counter32: udpliteNoPorts, udpliteInErrors,
         updliteInBadChecksum, udpliteEndpointViolCoverage

         - removed second, redundant MIB-2 number of udplite, following
         suggestion by Bill Fenner.

         - updated warning about maximum number of sub-identifiers in
         udpliteEndpointEntry, to reflect new structure

         - udplite now comes as entry number 1 in the udpliteMIB tree

         - accordingly changed the identifier of udpliteMIBConformance
         to 2





Renker & Fairhurst         Expires May 1, 2008                 [Page 30]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


         - updated all RFC editor notes with regard to the assignment of
         mib-2 identifier numbers (now only a single one required)

         - updated section `IANA Considerations' with regard to this
         change

         - removed the InBadCoverage counter since it is subsumed by
         InBadChecksum (see below)

         - updated the following identifier numbers for consistency
         after removal: udpliteInBadChecksum (6 -> 5),
         udpliteOutDatagrams (7 -> 6), udpliteOutPartialCov (8 -> 7),
         udpliteEndpointTable (9 -> 8)

         - removed udpliteInBadCoverage from udplitePartialCsumGroup

         - extended the definition of InBadChecksum to include invalid
         checksum coverage

         - added RFC 3828 references for udpliteEndpointMinCoverage and
         udpliteEndpointViolCoverage

         - updated the description of udpliteEndpointInstance with
         respect to draft-persson-v6ops-mib-issue-01.txt, section 3.2

   o  Section 7 (References):

         - RFC 4113 (UDP MIB) becomes informative, not normative

   o  Note on the removal of InBadCoverage: Following rev-01, this
      counter has been removed since - with the exception of obviously
      buggy UDP-Lite stacks - it is subsumed by InBadChecksum.  An
      illegal checksum value which is not the cause of a buggy
      implementation will in practically all cases lead to an incorrect
      checksum value, so that one counter implies information inherent
      in the other.

   ====> END OF NOTE TO THE RFC EDITOR <====













Renker & Fairhurst         Expires May 1, 2008                 [Page 31]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


7.  References

7.1.  Normative References

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

   [RFC2578]  McCloghrie, K., 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.

   [RFC3828]  Larzon, L-A., Degermark, M., Pink, S., Jonsson, L-E., and
              G. Fairhurst, "The Lightweight User Datagram Protocol
              (UDP-Lite)", RFC 3828, July 2004.

   [RFC4001]  Daniele, M., Haberman, B., Routhier, S., and J.
              Schoenwaelder, "Textual Conventions for Internet Network
              Addresses", RFC 4001, February 2005.

7.2.  Informative References

   [CASE]     Case, J. and C. Partridge, "Case Diagrams: A First Step to
              Diagrammed Management Information Bases", ACM Computer
              Communications Review, 19(1):13-16, January 1989.

   [RFC0768]  Postel, J., "User Datagram Protocol", STD 6, RFC 768,
              August 1980.

   [RFC2287]  Krupczak, C. and J. Saperia, "Definitions of System-Level
              Managed Objects for Applications", RFC 2287,
              February 1998.

   [RFC2790]  Waldbusser, S. and P. Grillo, "Host Resources MIB",
              RFC 2790, March 2000.

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




Renker & Fairhurst         Expires May 1, 2008                 [Page 32]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


   [RFC4113]  Fenner, B. and J. Flick, "Management Information Base for
              the User Datagram Protocol (UDP)", RFC 4113, June 2005.

   [RFC4340]  Kohler, E., Handley, M., and S. Floyd, "Datagram
              Congestion Control Protocol (DCCP)", RFC 4340, March 2006.














































Renker & Fairhurst         Expires May 1, 2008                 [Page 33]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


Authors' Addresses

   Gerrit Renker
   University of Aberdeen
   School of Engineering
   Fraser Noble Building
   Aberdeen  AB24 3UE
   Scotland

   Email: gerrit@erg.abdn.ac.uk
   URI:   http://www.erg.abdn.ac.uk


   Godred Fairhurst
   University of Aberdeen
   School of Engineering
   Fraser Noble Building
   Aberdeen  AB24 3UE
   Scotland

   Email: gorry@erg.abdn.ac.uk
   URI:   http://www.erg.abdn.ac.uk





























Renker & Fairhurst         Expires May 1, 2008                 [Page 34]

Internet-Draft        MIB for the UDP-Lite protocol         October 2007


Full Copyright Statement

   Copyright (C) The IETF Trust (2007).

   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.

   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, THE IETF TRUST 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.


Intellectual Property

   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.


Acknowledgment

   Funding for the RFC Editor function is provided by the IETF
   Administrative Support Activity (IASA).





Renker & Fairhurst         Expires May 1, 2008                 [Page 35]


Html markup produced by rfcmarkup 1.109, available from https://tools.ietf.org/tools/rfcmarkup/