Technical Summary
The Autonomous System (AS) number is encoded as a two-octet entity in
the base BGP specification. This document describes extensions to BGP
to carry the Autonomous System numbers as four-octet entities.
The primary difference between RFC 4893 and this draft is the
introduction of a detailed Error Handling section. Several other
requirements are also clarified or added.
Working Group Summary
One working group member, John Leslie, contributed a detailed review
of the draft which suggested extensive changes in terminology. The
authors disagreed as to the need for the changes. When the chairs put
the question to the WG directly, there was no support for pushing
forward with the changes, and some opposition.
During IETF Last Call one reviewer objected to the paragraph in section
6 stating :
"In addition, the path segment types AS_CONFED_SEQUENCE and
AS_CONFED_SET [RFC5065] MUST NOT be carried in the AS4_PATH attribute
of an UPDATE message. A NEW BGP speaker that receives these path
segment types in the AS4_PATH attribute of an UPDATE message from an
OLD BGP speaker MUST discard these path segments, adjust the relevant
attribute fields accordingly, and continue processing the UPDATE
message. This case SHOULD be logged locally for analysis."
There was no support for this position and several emails validating
its inclusion.
Document Quality
The protocol (extension) has been implemented and fielded
for years and it is generally considered to be a requirement
for a serious BGP implementation.
Personnel
The Document Shepherd is John Scudder.
The Responsible Area Director is Stewart Bryant.
RFC Editor Note
In the metadata please add "Updates: RFC4271"
=====
In the Abstract
Old
This document obsoletes RFC 4893.
New
This document obsoletes RFC 4893 and updates RFC4271
End
=====
Before section 8 add a new section with the following title and
text:
<heading> Manageability Considerations
If BGP-4 MIB [RFC4273] is supported, there are no additional
manageability concerns that arise with from the use of four octet AS
numbers, since the InetAutonomousSystemNumber textual convention is
defined as an unsigned32.
When IPFIX export [RFC5101] is supported, there are no additional
manageability concerns that arise from the use of four octet AS numbers.
The bgpSourceAsNumber and bgpDestinationAsNumber information elements
[http://www.iana.org/assignments/ipfix/ipfix.xml] can continued to be
used, with a new template record, specifying the new length of 4 bytes.
===
Please add informational reference
[http://www.iana.org/assignments/ipfix/ipfix.xml]
===
At the end of the Introduction
OLD:
This document obsoletes RFC 4893, and a comparison with RFC 4893 is
provided in Appendix A.
NEW:
This document obsoletes RFC 4893. It includes several clarifications
and editorial changes, and specifies the error handling for the new
attributes.
END
===
Please delete Appendix A
===