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

Versions: (RFC 3195) 00

Network Working Group                                             D. New
Internet-Draft
Obsoletes: 3195 (if approved)                                    M. Rose
Intended status: Standards Track            Dover Beach Consulting, Inc.
Expires: May 11, 2008                                            E. Lear
                                                           Cisco Systems
                                                        November 8, 2007


                      Reliable Delivery for syslog
                    draft-ietf-syslog-rfc3195bis-00

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 11, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2007).











New, et al.               Expires May 11, 2008                  [Page 1]

Internet-Draft        Reliable Delivery for syslog         November 2007


Abstract

   The syslog protocol describes a number of service options related to
   propagating event messages.  This memo describes a mapping of the
   syslog protocol to TCP connections, useful for reliable delivery of
   event messages through the use of a BEEP profile.  The earlier RAW
   and COOKED BEEP syslog profiles are deprecated.  The use of syslog
   over BEEP provides robustness and security in message delivery that
   is unavailable to the usual UDP-based syslog protocol, by providing
   encryption and authentication over a connection-oriented protocol.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  The Model  . . . . . . . . . . . . . . . . . . . . . . . . . .  4
   3.  The TARTARE Profile  . . . . . . . . . . . . . . . . . . . . .  5
     3.1.  TARTARE Profile Overview . . . . . . . . . . . . . . . . .  5
     3.2.  TARTARE Profile Identification and Initialization  . . . .  7
     3.3.  TARTARE Profile Message Syntax . . . . . . . . . . . . . .  8
     3.4.  TARTARE Profile Message Semantics  . . . . . . . . . . . .  8
   4.  Additional Provisioning  . . . . . . . . . . . . . . . . . . .  9
     4.1.  Message Authenticity . . . . . . . . . . . . . . . . . . .  9
     4.2.  Message Replay . . . . . . . . . . . . . . . . . . . . . .  9
     4.3.  Message Integrity  . . . . . . . . . . . . . . . . . . . .  9
     4.4.  Message Observation  . . . . . . . . . . . . . . . . . . .  9
     4.5.  Summary of Recommended Practices . . . . . . . . . . . . . 10
   5.  Registrations  . . . . . . . . . . . . . . . . . . . . . . . . 11
     5.1.  Registration: The TARTARE Profile  . . . . . . . . . . . . 11
   6.  Reply Codes  . . . . . . . . . . . . . . . . . . . . . . . . . 12
   7.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 13
     7.1.  Registration: BEEP Profile . . . . . . . . . . . . . . . . 13
     7.2.  Registration: The System (Well-Known) TCP port number
           for syslog-conn  . . . . . . . . . . . . . . . . . . . . . 13
   8.  Security Considerations  . . . . . . . . . . . . . . . . . . . 14
   9.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 15
   10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16
     10.1. Normative References . . . . . . . . . . . . . . . . . . . 16
     10.2. Informative References . . . . . . . . . . . . . . . . . . 16
   Appendix A.  Coexistence with old RAW and COOKED modes . . . . . . 17
   Appendix B.  Changes from RFC 3195 . . . . . . . . . . . . . . . . 18
   Appendix C.  To Do . . . . . . . . . . . . . . . . . . . . . . . . 19
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 20
   Intellectual Property and Copyright Statements . . . . . . . . . . 21







New, et al.               Expires May 11, 2008                  [Page 2]

Internet-Draft        Reliable Delivery for syslog         November 2007


1.  Introduction

   The syslog protocol [1] presents a spectrum of service options for
   provisioning an event-based logging service over a network.  Each
   option has associated benefits and costs.  Accordingly, the choice as
   to what combination of options is provisioned is both an engineering
   and administrative decision.  This memo describes how to realize the
   syslog protocol when reliable delivery is selected as a required
   service.  It is beyond the scope of this memo to argue for, or
   against, the use of reliable delivery for the syslog protocol.

   This memo is a revision of previous work [9].  Based on
   implementation and deployment experience, and the expectation of new
   work in the field, the principle changes to this document are these:

   o  Both the COOKED and the RAW profiles are deprecated.  The COOKED
      profile is deprecated because there has been no substantial
      deployment and it is no longer consistent with the work done in
      [1].

   o  The RAW profile is reproduced as a new profile, TARTARE, that has
      no length limitations.  Removal of the 1024 octet limitation is
      necessary for future worked in the area of "signed syslog".
      Previous length limitations continue to apply to the deprecated
      RAW and COOKED profiles.

   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 [2].






















New, et al.               Expires May 11, 2008                  [Page 3]

Internet-Draft        Reliable Delivery for syslog         November 2007


2.  The Model

   The reader is referred to [1] for the authoritative explanation of
   the syslog model.  What follows are issues relating to that model
   that are specific to BEEP and this mapping.

   It should be noted that a role of sender, relay, or collector is
   relevant only to a particular BEEP channel (q.v., below).  A single
   server can serve as a sender, a relay, and a collector, all at once,
   if so configured.  It can even serve as a relay and a collector to
   the same sender or device at the same time using different BEEP
   channels over the same connection-oriented session; this might be
   useful to collect status yet relay urgent error messages.

   To provide reliable delivery when realizing the syslog protocol, this
   memo defines a new BEEP profile.  BEEP [3] is a generic application
   protocol framework for connection-oriented, asynchronous
   interactions.  Within BEEP, features such as authentication, privacy,
   and reliability through retransmission are provided.  The new TARTARE
   profile is designed to provide a high-performance, low-impact
   footprint, using essentially the same format as the existing UDP-
   based syslog service.

   BEEP defines "transport mappings," specifying how BEEP messages are
   carried over the underlying transport technologies.  At the time of
   this writing, only one such transport is defined, in [4], which
   specifies BEEP over TCP.  All transport mappings are required to
   support enough reliability and sequencing to allow all BEEP messages
   on a given channel to be delivered reliably and in order.  Hence, the
   TARTARE profile provides reliable delivery of messages.

   Senders and relays MAY discover relays and collectors via the DNS SRV
   algorithm [5].  If so configured, the service used is "syslog" and
   the protocol used is "tcp".  This allows for central administration
   of addressing, fallback for failed relays and collectors, and static
   load balancing.  Security policies and hardware configurations may be
   such that device configuration is more secure than the DNS server.
   Hardware devices may be of such limited resources that DNS SRV access
   is inappropriate.  Firewalls and other restrictive routing mechanisms
   may need to be dealt with before a reliable syslog connection can be
   established.  In these cases, DNS might not be the most appropriate
   configuration mechanism.









New, et al.               Expires May 11, 2008                  [Page 4]

Internet-Draft        Reliable Delivery for syslog         November 2007


3.  The TARTARE Profile

3.1.  TARTARE Profile Overview

   The TARTARE profile is designed for minimal implementation effort,
   high efficiency, and backwards compatibility.

   It should be noted that even though the TARTARE profile uses the same
   format for message payloads as the UDP version of syslog uses,
   delivery is reliable.  The TARTARE syslog profile is a profile of
   BEEP [3], and BEEP guarantees ordered reliable delivery of messages
   within each individual channel.

   When the profile is started, no piggyback data is supplied.  All BEEP
   messages in the TARTARE profile are specified as having a MIME
   Content-Type [6] of application/octet-stream.  Once the channel is
   open, the listener (not the initiator) sends a MSG message indicating
   it is ready to act as a syslog sink.  (Refer to [3]'s Section 2.1 for
   a discussion of roles that a BEEP peer may perform, including
   definitions of the terms "listener", "initiator", "client", and
   "server".)

   The initiator uses ANS replies to supply one or more syslog entries
   in the current format, as specified in [1].  When the initiator has
   no more entries to send, it finishes with a NUL reply and closes the
   channel.

   An example might appear as follows:

   L: <wait for incoming connection>
   I: <establish connection>
   L: RPY 0 0 . 0 131
   L: Content-type: application/beep+xml
   L:
   L: <greeting>
   L:  <profile uri='http://xml.resource.org/profiles/syslog/TARTARE' />
   L: </greeting>
   L: END
   I: RPY 0 0 . 0 52
   I: Content-type: application/beep+xml
   I:
   I: <greeting />
   I: END
   I: MSG 0 1 . 52 136
   I: Content-type: application/beep+xml
   I:
   I: <start number='1'>
   I:  <profile uri='http://xml.resource.org/profiles/syslog/TARTARE' />



New, et al.               Expires May 11, 2008                  [Page 5]

Internet-Draft        Reliable Delivery for syslog         November 2007


   I: </start>
   I: END
   L: RPY 0 1 . 131 105
   L: Content-type: application/beep+xml
   L:
   L: <profile uri='http://xml.resource.org/profiles/syslog/TARTARE' />
   L: END
   L: MSG 1 0 . 0 50
   L:
   L: Central Services. This has not been a recording.
   L: END
   I: ANS 1 0 . 0 112
   I:
   I: <34>1 2003-10-11T22:14:15.003Z mymachine.example.com su - ID47
      - BOM'su root' failed for lonvick on /dev/pts/8END
   I: ANS 1 0 . 112 101 1
   I:
   I: <165>1 2003-08-24T05:14:15.000003-07:00 192.0.2.1
      myproc 8710 - - %% It's time to make the do-nuts.END
   I: NUL 1 0 . 222 0
   I: END
   L: MSG 0 3 . 236 70
   L: Content-Type: application/beep+xml
   L:
   L: <close number='1' code='200' />
   L: END
   I: RPY 0 3 . 188 46
   I: Content-Type: application/beep+xml
   I:
   I: <ok />
   I: END
   I: MSG 0 4 . 234 72
   I: Content-Type: application/beep+xml
   I:
   I: <close number='0' code='200' />
   I: END
   L: RPY 0 4 . 306 46
   L: Content-type: application/beep+xml
   L:
   L: <ok />
   L: END
   L: <closes connection>
   I: <closes connection>
   L: <awaits next connection>







New, et al.               Expires May 11, 2008                  [Page 6]

Internet-Draft        Reliable Delivery for syslog         November 2007


   Here we see a BEEP session established, followed by the use of the
   TARTARE profile.  The initiator is a sender, while the listener is a
   collector.  The initiator opens the channel, but the listener sends
   the first MSG.  This allows the initiator to send any number of ANS
   replies carrying syslog event messages.  The initiator sends a NUL
   reply to indicate it is finished.  Upon receiving the NUL, the
   listener closes the TARTARE channel.  The initiator has the choice of
   closing the entire BEEP session or opening a new syslog channel for
   more transfers.  In this example, the initiator chooses to close the
   entire BEEP session.  (Please note that in the example, as an
   artifact of the format of this memo, the two lines not beginning with
   I: or L: have been wrapped.)

   The overhead for one ANS frame is about thirty octets, once the
   initial handshakes have been exchanged.  If this overhead is too
   high, then messages are likely being generated at a high rate.  In
   this case, multiple syslog messages can be aggregated into a single
   ANS frame, each separated by a CRLF sequence from the preceding.  The
   final message still MUST NOT end with a CRLF.

   For example,

      L: MSG 1 0 . 0 50
      L:
      L: Central Services. This has not been a recording.
      L: END
      I: ANS 1 0 . 0 213 0
      I:
      I: <34>1 2003-10-11T22:14:15.003Z mymachine.example.com su - ID47
         - BOM'su root' failed for lonvick on /dev/pts/8
      I: <165>1 2003-08-24T05:14:15.000003-07:00 192.0.2.1
           myproc 8710 - - %% It's time to make the do-nuts.END
      I: NUL 1 0 . 213 0
      I: END

   (Again, as an artifact of the format of this memo, the two lines
   containing syslog entries have been wrapped.)

3.2.  TARTARE Profile Identification and Initialization

   The TARTARE syslog profile is identified as

           http://xml.resource.org/profiles/syslog/TARTARE

   in the BEEP "profile" element during channel creation.

   No data is piggybacked during channel creation.




New, et al.               Expires May 11, 2008                  [Page 7]

Internet-Draft        Reliable Delivery for syslog         November 2007


3.3.  TARTARE Profile Message Syntax

   All BEEP messages in this profile have a MIME content-type of
   application/octet-stream.  The listener's first BEEP message is
   ignored and indeed may be empty except for headers; hence, any syntax
   is acceptable.

   The ANS replies the initiator sends in response MUST be formatted
   according to Section 6 of [1].  In particular, If the receiver is
   acting as a relay, then it is expected follow the principles laid out
   in that specification.

   If multiple syslog messages are included in a single ANS reply, each
   is separated from the preceding with a CRLF.  There is no ending
   delimiter, and there is no length limitation.  Note that there MUST
   NOT be a CRLF between the text of the final syslog event message and
   the "END" marking the trailer of the BEEP frame.

3.4.  TARTARE Profile Message Semantics

   The listener's opening BEEP MSG message has no semantics.  (It is a
   good place to put in an identifying greeting.)  The initiator's ANS
   replies MUST specify a facility, severity, and textual message, as
   described in [1].



























New, et al.               Expires May 11, 2008                  [Page 8]

Internet-Draft        Reliable Delivery for syslog         November 2007


4.  Additional Provisioning

   In more advanced configurations, syslog senders, relays, and
   collectors can be configured to support various delivery priorities.
   Multiple channels running the same profile can be opened between two
   peers, with higher priority syslog messages routed to a channel that
   is given more bandwidth.  Such provisioning is a local matter.

   syslog [8] discusses a number of reasons why privacy and
   authentication of syslog entry messages may be important in a
   networked computing environment.  The nature of BEEP allows for
   convenient layering of authentication and privacy over any BEEP
   channel.

4.1.  Message Authenticity

   Section 8.7 of [1] discusses the dangers of unauthenticated syslog
   entries.  To prevent inauthentic syslog event messages from being
   accepted, configure syslog peers to require the use of a strong
   authentication technology for the BEEP session.

   If provisioned for message authentication, implementations SHOULD use
   SASL mechanism DIGEST-MD5 [7] to provision this service.

4.2.  Message Replay

   Section 8.4 of [1] discusses the dangers of syslog message replay.
   To prevent syslog event messages from being replayed, configure
   syslog peers to require the use of a strong authentication technology
   for the BEEP session.

   If provisioned to detect message replay, implementations SHOULD use
   SASL mechanism DIGEST-MD5 [7] to provision this service.

4.3.  Message Integrity

   Section 6.5 of [8] discusses the dangers of syslog event messages
   being maliciously altered by an attacker.  To prevent messages from
   being altered, configure syslog peers to require the use of a strong
   authentication technology for the BEEP session.

   If provisioned to protect message integrity, implementations SHOULD
   use SASL mechanism DIGEST-MD5 [7] to provision this service.

4.4.  Message Observation

   Section 6.6 of [8] discusses the dangers (and benefits) of syslog
   messages being visible at intermediate points along the transmission



New, et al.               Expires May 11, 2008                  [Page 9]

Internet-Draft        Reliable Delivery for syslog         November 2007


   path between sender and collector.  To prevent messages from being
   viewed by an attacker, configure syslog peers to require the use of a
   transport security profile for the BEEP session.  (However, other
   traffic characteristics, e.g., volume and timing of transmissions,
   remain observable.)

   If provisioned to secure messages against unauthorized observation,
   implementations SHOULD use the TLS profile [3] to provision this
   service.  The cipher algorithm used SHOULD be configurable, minimally
   supporting TLS_RSA_WITH_3DES_EDE_CBC_SHA for backward compatability
   and TLS_RSA_WITH_AES_256_CBC_SHA for stronger protection.  It is
   expected that new algorithms will need to be added as time passes, in
   order to prevent compromise.  No new revision of this memo should be
   expected solely for that reason.

4.5.  Summary of Recommended Practices

   For the indicated protections, implementations SHOULD be configured
   to use the indicated mechanisms:

    Desired Protection  SHOULD tune using
    ------------------  -----------------
    Authentication      http://iana.org/beep/SASL/DIGEST-MD5
      + Replay          http://iana.org/beep/SASL/DIGEST-MD5
        + Integrity     http://iana.org/beep/SASL/DIGEST-MD5
          + Observation http://iana.org/beep/TLS


   BEEP peer identities used for authentication SHOULD correspond to the
   FQDN of the initiating peer.  That is, a relay running on
   relay.example.com should use a "user ID" of "relay.example.com"
   within the SASL authentication profiles.



















New, et al.               Expires May 11, 2008                 [Page 10]

Internet-Draft        Reliable Delivery for syslog         November 2007


5.  Registrations

5.1.  Registration: The TARTARE Profile

   Profile Identification:
      http://xml.resource.org/profiles/syslog/TARTARE

   Messages exchanged during Channel Creation:  None

   Messages starting one-to-one exchanges:  Anything

   Messages in positive replies:  None

   Messages in negative replies:  None

   Messages in one-to-many exchanges:  Anything

   Message Syntax:  See Section 3.3

   Message Semantics:  See Section 3.4

   Contact Information:  See the "Authors' Addresses" section of this
      memo




























New, et al.               Expires May 11, 2008                 [Page 11]

Internet-Draft        Reliable Delivery for syslog         November 2007


6.  Reply Codes

   The following error codes are used in the protocol:

   code    meaning
   ====    =======
   200     success

   421     service not available

   451     requested action aborted
           (e.g., local error in processing)

   454     temporary authentication failure

   500     general syntax error
           (e.g., poorly-formed XML)

   501     syntax error in parameters
           (e.g., non-valid XML)

   504     parameter not implemented

   530     authentication required

   534     authentication mechanism insufficient
           (e.g., too weak, sequence exhausted, etc.)

   535     authentication failure

   537     action not authorized for user

   538     authentication mechanism requires encryption

   550     requested action not taken
           (e.g., no requested profiles are acceptable)

   553     parameter invalid

   554     transaction failed
           (e.g., policy violation)










New, et al.               Expires May 11, 2008                 [Page 12]

Internet-Draft        Reliable Delivery for syslog         November 2007


7.  IANA Considerations

   The IANA is requested to note in their registrations that both
   http://iana.org/beep/SYSLOG/RAW and
   http://iana.org/beep/SYSLOG/COOKED are deprecated.  In addition, the
   IANA is requested to register the profile listed below.

7.1.  Registration: BEEP Profile

   The IANA registers the profiles specified in Section 5, and selects
   IANA-specific URI "http://iana.org/beep/SYSLOG/TARTARE".

7.2.  Registration: The System (Well-Known) TCP port number for syslog-
      conn

   A single well-known port (601) is allocated to syslog-conn.  In-band
   negotiation determines which profile to use (either the one defined
   in this memo or one of the obsolete profiles).

   Protocol Number:  TCP

   Message Formats, Types, Opcodes, and Sequences:  See Section 3.3.

   Functions:  See Section 3.4.

   Use of Broadcast/Multicast:  none

   Proposed Name:  Reliable syslog service

   Short name:  syslog-conn

   Contact Information:  See the "Authors' Addresses" section of this
      memo


















New, et al.               Expires May 11, 2008                 [Page 13]

Internet-Draft        Reliable Delivery for syslog         November 2007


8.  Security Considerations

   Consult Section 8 of [1] for a discussion of security issues for the
   syslog service.  In addition, since the TARTARE profile is defined
   using the BEEP framework, consult [3]'s Section 8 for a discussion of
   BEEP-specific security issues.

   BEEP is used to provide communication security but not object
   integrity.  In other words, the messages "on the wire" can be
   protected, but a compromised sender may undetectably generate
   incorrect messages, and relays and collectors can modify, insert, or
   delete messages undetectably.  Other techniques must be used to
   assure that such compromises are detectable.






































New, et al.               Expires May 11, 2008                 [Page 14]

Internet-Draft        Reliable Delivery for syslog         November 2007


9.  Acknowledgements

   The authors gratefully acknowledge the contributions of Christopher
   Calabrese, Keith McCloghrie, Balazs Scheidler, and David Waitzman.















































New, et al.               Expires May 11, 2008                 [Page 15]

Internet-Draft        Reliable Delivery for syslog         November 2007


10.  References

10.1.  Normative References

   [1]  Gerhards, R., "The syslog Protocol",
        draft-ietf-syslog-protocol-22 (work in progress), August 2007.

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

   [3]  Rose, M., "The Blocks Extensible Exchange Protocol Core",
        RFC 3080, March 2001.

   [4]  Rose, M., "Mapping the BEEP Core onto TCP", RFC 3081,
        March 2001.

   [5]  Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for
        specifying the location of services (DNS SRV)", RFC 2782,
        February 2000.

   [6]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
        Extensions (MIME) Part Two: Media Types", RFC 2046,
        November 1996.

   [7]  Leach, P. and C. Newman, "Using Digest Authentication as a SASL
        Mechanism", RFC 2831, May 2000.

10.2.  Informative References

   [8]  Lonvick, C., "The BSD Syslog Protocol", RFC 3164, August 2001.

   [9]  New, D. and M. Rose, "Reliable Delivery for syslog", RFC 3195,
        November 2001.


















New, et al.               Expires May 11, 2008                 [Page 16]

Internet-Draft        Reliable Delivery for syslog         November 2007


Appendix A.  Coexistence with old RAW and COOKED modes

   This memo specifies a new profile for syslog messages that adhere to
   the specification in [1].  It is recommended that messages using the
   older format specified in [8] continue to make use of the deprecated
   RAW or COOKED profiles specified in [9].  This allows for easy
   separation of old and new syslog formats.












































New, et al.               Expires May 11, 2008                 [Page 17]

Internet-Draft        Reliable Delivery for syslog         November 2007


Appendix B.  Changes from RFC 3195

   o  Deprecated RAW and COOKED profiles.

   o  Shamelessly copied the RAW profile to a new name and updated it so
      that there is no length limitation.

   o  Split references into normative and informative

   o  In the new model, authors have chosen "sender" instead of
      "device".  We have adopted that language in this draft.

   o  Updated the language for TLS encryption algorithms to reflect
      current thinking.

   o  Use examples from [1]



































New, et al.               Expires May 11, 2008                 [Page 18]

Internet-Draft        Reliable Delivery for syslog         November 2007


Appendix C.  To Do

   o  Review connection termination.

   o  Check byte counts.














































New, et al.               Expires May 11, 2008                 [Page 19]

Internet-Draft        Reliable Delivery for syslog         November 2007


Authors' Addresses

   Darren New
   5390 Caminito Exquisito
   San Diego, CA  92130
   US

   Phone: +1 858 350 9733
   Email: dnew@san.rr.com


   Marshall T. Rose
   Dover Beach Consulting, Inc.
   POB 255268
   Sacramento, CA  95865-5268
   US

   Phone: +1 916 483 8878
   Email: mrose@dbc.mtview.ca.us


   Eliot Lear
   Cisco Systems
   Glatt-com
   Glattzentrum, Zurich  8301
   CH

   Email: lear@cisco.com























New, et al.               Expires May 11, 2008                 [Page 20]

Internet-Draft        Reliable Delivery for syslog         November 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).





New, et al.               Expires May 11, 2008                 [Page 21]


Html markup produced by rfcmarkup 1.107, available from http://tools.ietf.org/tools/rfcmarkup/