Technical Summary
This document defines extensions to BGP-4 to enable it to carry
routing information for multiple Network Layer protocols (e.g., IPv6,
IPX, L3VPN, etc...). The extensions are backward compatible - a router that
supports the extensions can interoperate with a router that doesn't
support the extensions.
In the move to Draft Standard, the support for SAFI 3 (unicast+
multicast for congruent topologies) was removed due to lack of
implementation support. The value remains reserved in case
this feature is implemented. In addition, the support for SNPA
was removed, also due to lack of implementation support.
The "Number of SNPAs" field was changed to reserved and
MUST be set to zero.
Working Group Summary
The working group had consensus to move this document to
Draft Standard.
Protocol Quality
Bill Fenner reviewed this spec for the IESG. There are several
implementations, as described in the accompanying implementation
report, which can be found at
http://www.ietf.org/IESG/Implementations/mp-bgp-implementation-report.txt
Note to RFC Editor
This document obsoletes RFC 2858.
Please make the following changes:
In the Abstract, remove the first sentence and add another example to the
list;
OLD:
Currently BGP-4 is capable of carrying routing information only for
IPv4. This document defines extensions to BGP-4 to enable it to carry
routing information for multiple Network Layer protocols (e.g., IPv6,
IPX, etc...). The extensions are backward compatible - a router that
NEW:
This document defines extensions to BGP-4 to enable it to carry
routing information for multiple Network Layer protocols (e.g., IPv6,
IPX, L3VPN, etc...). The extensions are backward compatible - a router that
OLD:
To
identify individual Network Layer protocols associated with the next
hop information and semantics of NLRI this document uses a
combination of Address Family, as defined in [RFC1700], and
Subsequent Address Family (as described in this document).
NEW:
To
identify individual Network Layer protocols associated with the next
hop information and semantics of NLRI this document uses a
combination of Address Family, as defined in [IANA-AF], and
Subsequent Address Family (as described in this document).
This paragraph appears twice, please change both:
OLD:
Presently defined values for the Address Family Identifier
field are specified in RFC1700 (see the Address Family Numbers
section).
NEW:
Presently defined values for the Address Family Identifier
field are specified in the IANA's Address Family Numbers
registry [IANA-AF].
In section 8:
OLD:
Res. - Reserved (8 bit) field. SHOULD be set to 0 by the sender
and ignored by the receiver.
NEW:
Res. - Reserved (8 bit) field. SHOULD be set to 0 by the sender
and ignored by the receiver.
Note that not setting the field value to 0 may create issues for a
receiver not ignoring the field. In addition this definition is
problematic if it is ever attempted to redefine the field.
In the IANA considerations section:
OLD:
- SAFI values 128 through 240 are part of the previous "private
use" range. Of this space, allocations which are currently in use
are to be recognized by IANA. Unused values, namely 130, 131, 135
through 139, and 141 through 240 should be considered reserved, in
order to avoid conflicts.
NEW:
- SAFI values 128 through 240 are part of the previous "private
use" range. At the time of approval of this document, a list of
allocations which are currently in use will be provided to IANA
by the Routing Area Director. Unused values, namely 130, 131, 135
through 139, and 141 through 240 should be considered reserved, in
order to avoid conflicts.
References:
OLD:
[BGP-CAP] "Capabilities Advertisement with BGP-4", R. Chandra, J.
Scudder, RFC2842, May 2000
[BGP-4] Rekhter, Y., and T. Li, "A Border Gateway Protocol 4
(BGP-4)", RFC 1771, March 1995.
[RFC1700] "Assigned Numbers", J. Reynolds, J. Postel, RFC1700,
October 1994 (see also http://www.iana.org/iana/assignments.html)
NEW:
[BGP-CAP] Chandra, R. and J. Scudder, "Capabilities Advertisement
with BGP-4", RFC 3392, November 2002.
[BGP-4] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway
Protocol 4 (BGP-4)", RFC 4271, January 2006.
[IANA-AF] "Address Family Numbers",
reachable from http://www.iana.org/numbers.html
Authors' Addresses: [change juniper.com to juniper.net]
OLD:
Dave Katz
Juniper Networks, Inc.
email: dkatz@juniper.com
Yakov Rekhter
Juniper Networks, Inc.
email: yakov@juniper.com
NEW:
Dave Katz
Juniper Networks, Inc.
email: dkatz@juniper.net
Yakov Rekhter
Juniper Networks, Inc.
email: yakov@juniper.net