draft-ietf-idr-cease-subcode-04.txt   draft-ietf-idr-cease-subcode-05.txt 
Network Working Group Enke Chen Network Working Group Enke Chen
Internet Draft Redback Networks Internet Draft Redback Networks
Expiration Date: March 2004 Vincent Gillet Expiration Date: October 2004 Vincent Gillet
France Telecom France Telecom
Subcodes for BGP Cease Notification Message Subcodes for BGP Cease Notification Message
draft-ietf-idr-cease-subcode-04.txt draft-ietf-idr-cease-subcode-05.txt
1. Status of this Memo 1. Status of this Memo
This document is an Internet-Draft and is in full conformance with This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026. all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet- other groups may also distribute working documents as Internet-
Drafts. Drafts.
skipping to change at page 2, line 5 skipping to change at page 2, line 5
The list of Internet-Draft Shadow Directories can be accessed at The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html. http://www.ietf.org/shadow.html.
2. Abstract 2. Abstract
This document defines several subcodes for the BGP Cease NOTIFICATION This document defines several subcodes for the BGP Cease NOTIFICATION
message that would provide more information to aid network operators message that would provide more information to aid network operators
in co-relating network events and diagnosing BGP peering issues. in co-relating network events and diagnosing BGP peering issues.
3. Introduction 3. Specification of Requirements
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 [RFC-2119].
4. Introduction
This document defines several subcodes for the BGP Cease NOTIFICATION This document defines several subcodes for the BGP Cease NOTIFICATION
message that would provide more information to aid network operators message that would provide more information to aid network operators
in co-relating network events and diagnosing BGP peering issues. in co-relating network events and diagnosing BGP peering issues.
4. Subcode Definition 5. Subcode Definition
The following subcodes are defined for the Cease NOTIFICATION The following subcodes are defined for the Cease NOTIFICATION
message: message:
Subcode Symbolic Name Subcode Symbolic Name
1 Maximum Number of Prefixes Reached 1 Maximum Number of Prefixes Reached
2 Administrative Shutdown 2 Administrative Shutdown
3 Peer Unconfigured 3 Peer Unconfigured
4 Administrative Reset 4 Administrative Reset
5 Connection Rejected 5 Connection Rejected
6 Other Configuration Change 6 Other Configuration Change
7 Connection Collision Resolution 7 Connection Collision Resolution
8 Out of Resource 8 Out of Resource
5. Subcode Usage 6. Subcode Usage
If a BGP speaker decides to terminate its peering with a neighbor If a BGP speaker decides to terminate its peering with a neighbor
because the number of address prefixes received from the neighbor because the number of address prefixes received from the neighbor
exceeds a locally configured upper bound (as described in [BGP-4]), exceeds a locally configured upper bound (as described in [BGP-4]),
then the speaker must send to the neighbor a NOTIFICATION message then the speaker MUST send to the neighbor a NOTIFICATION message
with the Error Code Cease, and the Error Subcode "Maximum Number of with the Error Code Cease, and the Error Subcode "Maximum Number of
Prefixes Reached". The message may optionally include the Address Prefixes Reached". The message MAY optionally include the Address
Family information [BGP-MP] and the upper bound in the "Data" field Family information [BGP-MP] and the upper bound in the "Data" field
with the following format: with the following format:
+-------------------------------+ +-------------------------------+
| AFI (2 octets) | | AFI (2 octets) |
+-------------------------------+ +-------------------------------+
| SAFI (1 octet) | | SAFI (1 octet) |
+-------------------------------+ +-------------------------------+
| Prefix upper bound (4 octets) | | Prefix upper bound (4 octets) |
+-------------------------------+ +-------------------------------+
where the meaning and use of the <AFI, SAFI> tuple is the same as where the meaning and use of the <AFI, SAFI> tuple is the same as
defined in [BGP-MP, sect. 7]. defined in [BGP-MP, sect. 7].
If a BGP speaker decides to administratively shut down its peering If a BGP speaker decides to administratively shut down its peering
with a neighbor, then the speaker should send a NOTIFICATION message with a neighbor, then the speaker SHOULD send a NOTIFICATION message
with the Error Code Cease, and the Error Subcode "Administrative with the Error Code Cease, and the Error Subcode "Administrative
Shutdown". Shutdown".
If a BGP speaker decides to unconfigure a peer, then the speaker If a BGP speaker decides to unconfigure a peer, then the speaker
should send a NOTIFICATION message with the Error Code Cease, and the SHOULD send a NOTIFICATION message with the Error Code Cease, and the
Error Subcode "Peer Unconfigured". Error Subcode "Peer Unconfigured".
If a BGP speaker decides to administratively reset the peering with a If a BGP speaker decides to administratively reset the peering with a
neighbor, then the speaker should send a NOTIFICATION message with neighbor, then the speaker SHOULD send a NOTIFICATION message with
the Error Code Cease, and the Error Subcode "Administrative Reset". the Error Code Cease, and the Error Subcode "Administrative Reset".
If a BGP speaker decides to dis-allow a BGP connection (e.g., the If a BGP speaker decides to dis-allow a BGP connection (e.g., the
peer is not configured locally) after the speaker accepts a transport peer is not configured locally) after the speaker accepts a transport
protocol connection, then the BGP speaker should send a NOTIFICATION protocol connection, then the BGP speaker SHOULD send a NOTIFICATION
message with the Error Code Cease, and the Error Subcode "Connection message with the Error Code Cease, and the Error Subcode "Connection
Rejected". Rejected".
If a BGP speaker decides to administratively reset the peering with a If a BGP speaker decides to administratively reset the peering with a
neighbor due to a configuration change other than the ones described neighbor due to a configuration change other than the ones described
above, then the speaker should send a NOTIFICATION message with the above, then the speaker SHOULD send a NOTIFICATION message with the
Error Code Cease, and the Error Subcode "Other Configuration Change". Error Code Cease, and the Error Subcode "Other Configuration Change".
If a BGP speaker decides to send a NOTIFICATION message with the If a BGP speaker decides to send a NOTIFICATION message with the
Error Code Cease as a result of the collision resolution procedure Error Code Cease as a result of the collision resolution procedure
(as described in [BGP-4]), then the subcode should be set to (as described in [BGP-4]), then the subcode SHOULD be set to
"Connection Collision Resolution". "Connection Collision Resolution".
If a BGP speaker runs out of resource (e.g., memory) and decides to If a BGP speaker runs out of resource (e.g., memory) and decides to
reset a session, then the speaker may send a NOTIFICATION message reset a session, then the speaker MAY send a NOTIFICATION message
with the Error Code Cease, and the Error Subcode "Out of Resource". with the Error Code Cease, and the Error Subcode "Out of Resource".
It is recommended that a BGP speaker implement a backoff mechanism in It is RECOMMENDED that a BGP speaker implement a backoff mechanism in
re-trying a BGP connection after the speaker receives a Cease re-trying a BGP connection after the speaker receives a Cease
NOTIFICATION message with subcode of "Administrative Shutdown", or NOTIFICATION message with subcode of "Administrative Shutdown", or
"Peer Unconfigured", or "Connection Rejected", or "Out of Resource". "Peer Unconfigured", or "Connection Rejected", or "Out of Resource".
An implementation may impose an upper bound on the number of An implementation MAY impose an upper bound on the number of
consecutive automatic retries. Once this bound is reached, the consecutive automatic retries. Once this bound is reached, the
implementation would stop re-trying any BGP connections until some implementation would stop re-trying any BGP connections until some
administrative intervention. administrative intervention.
6. IANA Considerations 7. IANA Considerations
This document defines several subcodes for the BGP Cease NOTIFICATION This document defines several subcodes for the BGP Cease NOTIFICATION
messsage. New subcodes MUST only be introduced using the Standards messsage. New subcodes MUST only be introduced using the Standards
Action process defined in [RFC-2434]. Action process defined in [RFC-2434].
7. Security Considerations 8. Security Considerations
This extension to BGP does not change the underlying security issues. This extension to BGP does not change the underlying security issues
inherent in the existing BGP.
8. Acknowledgments 9. Acknowledgments
The authors would like to thank Yakov Rekhter, Pedro Marques, Andrew The authors would like to thank Yakov Rekhter, Pedro Marques, Andrew
Lange and Don Goodspeed for their review and suggestions. Lange and Don Goodspeed for their review and suggestions.
9. References 10. References
[BGP-4] Y. Rekhter, T. Li and S. Hares, "A Border Gateway Protocol 4 [BGP-4] Y. Rekhter, T. Li and S. Hares, "A Border Gateway Protocol 4
(BGP-4)", <draft-ietf-idr-bgp4-20.txt>, April 2003. (BGP-4)", <draft-ietf-idr-bgp4-23.txt>, November 2003.
[BGP-MP] Bates, T., Chandra, R., Katz, D. and Y. Rekhter, [BGP-MP] Bates, T., Chandra, R., Katz, D. and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 2858, June 2000. "Multiprotocol Extensions for BGP-4", RFC 2858, June 2000.
[RFC-2434] Narten, T., Alvestrand, H., "Guidelines for Writing an [RFC-2434] Narten, T., Alvestrand, H., "Guidelines for Writing an
IANA Considerations Section in RFCs", RFC 2434, October 1998. IANA Considerations Section in RFCs", RFC 2434, October 1998.
10. Author Information [RFC-2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
11. Author Information
Enke Chen Enke Chen
Redback Networks, Inc. Redback Networks, Inc.
300 Holger Way 300 Holger Way
San Jose, CA 95134 San Jose, CA 95134
Email: enke@redback.com Email: enke@redback.com
Vincent Gillet Vincent Gillet
France Telecom Longues Distances France Telecom Longues Distances
246 rue de Bercy 246 rue de Bercy
 End of changes. 

This html diff was produced by rfcdiff 1.23, available from http://www.levkowetz.com/ietf/tools/rfcdiff/