draft-ietf-idr-rfc2858bis-10.txt   rfc4760.txt 
Network Working Group Tony Bates (Cisco Systems) Network Working Group T. Bates
Internet Draft Ravi Chandra (Sonoa Systems) Request for Comments: 4760 Cisco Systems
Expiration Date: September 2006 Dave Katz (Juniper Networks) Obsoletes: 2858 R. Chandra
Obsoles RFC2858 Yakov Rekhter (Juniper Networks) Category: Standards Track Sonoa Systems
D. Katz
Y. Rekhter
Juniper Networks
January 2007
Multiprotocol Extensions for BGP-4 Multiprotocol Extensions for BGP-4
draft-ietf-idr-rfc2858bis-10.txt Status of This Memo
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Official Protocol Standards" (STD 1) for the standardization state
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IPR Disclosure Acknowledgement Copyright Notice
By submitting this Internet-Draft, each author represents that any Copyright (C) The IETF Trust (2007).
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.
Abstract Abstract
Currently BGP-4 is capable of carrying routing information only for This document defines extensions to BGP-4 to enable it to carry
IPv4. This document defines extensions to BGP-4 to enable it to carry
routing information for multiple Network Layer protocols (e.g., IPv6, routing information for multiple Network Layer protocols (e.g., IPv6,
IPX, etc...). The extensions are backward compatible - a router that IPX, L3VPN, etc.). The extensions are backward compatible - a router
supports the extensions can interoperate with a router that doesn't that supports the extensions can interoperate with a router that
support the extensions. doesn't support the extensions.
1. 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 [RFC2119].
2. Overview 1. Introduction
The only three pieces of information carried by BGP-4 [BGP-4] that The only three pieces of information carried by BGP-4 [BGP-4] that
are IPv4 specific are (a) the NEXT_HOP attribute (expressed as an are IPv4 specific are (a) the NEXT_HOP attribute (expressed as an
IPv4 address), (b) AGGREGATOR (contains an IPv4 address), and (c) IPv4 address), (b) AGGREGATOR (contains an IPv4 address), and (c)
NLRI (expressed as IPv4 address prefixes). This document assumes that NLRI (expressed as IPv4 address prefixes). This document assumes
any BGP speaker (including the one that supports multiprotocol that any BGP speaker (including the one that supports multiprotocol
capabilities defined in this document) has to have an IPv4 address capabilities defined in this document) has to have an IPv4 address
(which will be used, among other things, in the AGGREGATOR (which will be used, among other things, in the AGGREGATOR
attribute). Therefore, to enable BGP-4 to support routing for attribute). Therefore, to enable BGP-4 to support routing for
multiple Network Layer protocols the only two things that have to be multiple Network Layer protocols, the only two things that have to be
added to BGP-4 are (a) the ability to associate a particular Network added to BGP-4 are (a) the ability to associate a particular Network
Layer protocol with the next hop information, and (b) the ability to Layer protocol with the next hop information, and (b) the ability to
associated a particular Network Layer protocol with NLRI. To associate a particular Network Layer protocol with NLRI. To identify
identify individual Network Layer protocols associated with the next individual Network Layer protocols associated with the next hop
hop information and semantics of NLRI this document uses a information and semantics of NLRI, this document uses a combination
combination of Address Family, as defined in [RFC1700], and of Address Family, as defined in [IANA-AF], and Subsequent Address
Subsequent Address Family (as described in this document). Family (as described in this document).
One could further observe that the next hop information (the One could further observe that the next hop information (the
information provided by the NEXT_HOP attribute) is meaningful (and information provided by the NEXT_HOP attribute) is meaningful (and
necessary) only in conjunction with the advertisements of reachable necessary) only in conjunction with the advertisements of reachable
destinations - in conjunction with the advertisements of unreachable destinations - in conjunction with the advertisements of unreachable
destinations (withdrawing routes from service) the next hop destinations (withdrawing routes from service), the next hop
information is meaningless. This suggests that the advertisement of information is meaningless. This suggests that the advertisement of
reachable destinations should be grouped with the advertisement of reachable destinations should be grouped with the advertisement of
the next hop to be used for these destinations, and that the the next hop to be used for these destinations, and that the
advertisement of reachable destinations should be segregated from the advertisement of reachable destinations should be segregated from the
advertisement of unreachable destinations. advertisement of unreachable destinations.
To provide backward compatibility, as well as to simplify To provide backward compatibility, as well as to simplify
introduction of the multiprotocol capabilities into BGP-4 this introduction of the multiprotocol capabilities into BGP-4, this
document uses two new attributes, Multiprotocol Reachable NLRI document uses two new attributes, Multiprotocol Reachable NLRI
(MP_REACH_NLRI), and Multiprotocol Unreachable NLRI (MP_REACH_NLRI) and Multiprotocol Unreachable NLRI (MP_UNREACH_NLRI).
(MP_UNREACH_NLRI). The first one (MP_REACH_NLRI) is used to carry the The first one (MP_REACH_NLRI) is used to carry the set of reachable
set of reachable destinations together with the next hop information destinations together with the next hop information to be used for
to be used for forwarding to these destinations. The second one forwarding to these destinations. The second one (MP_UNREACH_NLRI)
(MP_UNREACH_NLRI) is used to carry the set of unreachable is used to carry the set of unreachable destinations. Both of these
destinations. Both of these attributes are optional and non- attributes are optional and non-transitive. This way, a BGP speaker
transitive. This way a BGP speaker that doesn't support the that doesn't support the multiprotocol capabilities will just ignore
multiprotocol capabilities will just ignore the information carried the information carried in these attributes and will not pass it to
in these attributes, and will not pass it to other BGP speakers. other BGP speakers.
2. 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 [RFC2119].
3. Multiprotocol Reachable NLRI - MP_REACH_NLRI (Type Code 14): 3. Multiprotocol Reachable NLRI - MP_REACH_NLRI (Type Code 14):
This is an optional non-transitive attribute that can be used for the This is an optional non-transitive attribute that can be used for the
following purposes: following purposes:
(a) to advertise a feasible route to a peer (a) to advertise a feasible route to a peer
(b) to permit a router to advertise the Network Layer address of (b) to permit a router to advertise the Network Layer address of the
the router that should be used as the next hop to the destinations router that should be used as the next hop to the destinations
listed in the Network Layer Reachability Information field of the listed in the Network Layer Reachability Information field of the
MP_NLRI attribute. MP_NLRI attribute.
The attribute is encoded as shown below: The attribute is encoded as shown below:
+---------------------------------------------------------+ +---------------------------------------------------------+
| Address Family Identifier (2 octets) | | Address Family Identifier (2 octets) |
+---------------------------------------------------------+ +---------------------------------------------------------+
| Subsequent Address Family Identifier (1 octet) | | Subsequent Address Family Identifier (1 octet) |
+---------------------------------------------------------+ +---------------------------------------------------------+
skipping to change at line 127 skipping to change at page 3, line 38
| Reserved (1 octet) | | Reserved (1 octet) |
+---------------------------------------------------------+ +---------------------------------------------------------+
| Network Layer Reachability Information (variable) | | Network Layer Reachability Information (variable) |
+---------------------------------------------------------+ +---------------------------------------------------------+
The use and meaning of these fields are as follows: The use and meaning of these fields are as follows:
Address Family Identifier (AFI): Address Family Identifier (AFI):
This field in combination with the Subsequent Address Family This field in combination with the Subsequent Address Family
Identifier field identifies the Network Layer protocol Identifier field identifies the set of Network Layer protocols
associated with the Network Address of Next Hop and the to which the address carried in the Next Hop field must belong,
semantics of the Network Layer Reachability Information that the way in which the address of the next hop is encoded, and
follows. the semantics of the Network Layer Reachability Information
that follows. If the Next Hop is allowed to be from more than
one Network Layer protocol, the encoding of the Next Hop MUST
provide a way to determine its Network Layer protocol.
Presently defined values for the Address Family Identifier Presently defined values for the Address Family Identifier
field are specified in RFC1700 (see the Address Family Numbers field are specified in the IANA's Address Family Numbers
section). registry [IANA-AF].
Subsequent Address Family Identifier (SAFI): Subsequent Address Family Identifier (SAFI):
This field in combination with the Address Family Identifier This field in combination with the Address Family Identifier
field identifies the Network Layer protocol associated with the field identifies the set of Network Layer protocols to which
Network Address of the Next Hop and the semantics of the the address carried in the Next Hop must belong, the way in
Network Layer Reachability Information that follows. which the address of the next hop is encoded, and the semantics
of the Network Layer Reachability Information that follows. If
the Next Hop is allowed to be from more than one Network Layer
protocol, the encoding of the Next Hop MUST provide a way to
determine its Network Layer protocol.
Length of Next Hop Network Address: Length of Next Hop Network Address:
A 1 octet field whose value expresses the length of the A 1-octet field whose value expresses the length of the
"Network Address of Next Hop" field as measured in octets. "Network Address of Next Hop" field, measured in octets.
Network Address of Next Hop: Network Address of Next Hop:
A variable length field that contains the Network Address of A variable-length field that contains the Network Address of
the next router on the path to the destination system. The the next router on the path to the destination system. The
Network Layer protocol associated with the Network Address of Network Layer protocol associated with the Network Address of
the Next Hop is identified by a combination of <AFI, SAFI> the Next Hop is identified by a combination of <AFI, SAFI>
carried in the attribute. carried in the attribute.
Reserved: Reserved:
A 1 octet field that MUST be set to 0, and SHOULD be ignored A 1 octet field that MUST be set to 0, and SHOULD be ignored
upon receipt. upon receipt.
skipping to change at line 195 skipping to change at page 5, line 22
carry the LOCAL_PREF attribute. carry the LOCAL_PREF attribute.
An UPDATE message that carries no NLRI, other than the one encoded in An UPDATE message that carries no NLRI, other than the one encoded in
the MP_REACH_NLRI attribute, SHOULD NOT carry the NEXT_HOP attribute. the MP_REACH_NLRI attribute, SHOULD NOT carry the NEXT_HOP attribute.
If such a message contains the NEXT_HOP attribute, the BGP speaker If such a message contains the NEXT_HOP attribute, the BGP speaker
that receives the message SHOULD ignore this attribute. that receives the message SHOULD ignore this attribute.
An UPDATE message SHOULD NOT include the same address prefix (of the An UPDATE message SHOULD NOT include the same address prefix (of the
same <AFI, SAFI>) in more than one of the following fields: WITHDRAWN same <AFI, SAFI>) in more than one of the following fields: WITHDRAWN
ROUTES field, Network Reachability Information fields, MP_REACH_NLRI ROUTES field, Network Reachability Information fields, MP_REACH_NLRI
field, and MP_UNREACH_NLRI field. The processing of an UPDATE message field, and MP_UNREACH_NLRI field. The processing of an UPDATE
in this form is un-defined. message in this form is undefined.
4. Multiprotocol Unreachable NLRI - MP_UNREACH_NLRI (Type Code 15): 4. Multiprotocol Unreachable NLRI - MP_UNREACH_NLRI (Type Code 15):
This is an optional non-transitive attribute that can be used for the This is an optional non-transitive attribute that can be used for the
purpose of withdrawing multiple unfeasible routes from service. purpose of withdrawing multiple unfeasible routes from service.
The attribute is encoded as shown below: The attribute is encoded as shown below:
+---------------------------------------------------------+ +---------------------------------------------------------+
| Address Family Identifier (2 octets) | | Address Family Identifier (2 octets) |
skipping to change at line 218 skipping to change at page 5, line 45
| Subsequent Address Family Identifier (1 octet) | | Subsequent Address Family Identifier (1 octet) |
+---------------------------------------------------------+ +---------------------------------------------------------+
| Withdrawn Routes (variable) | | Withdrawn Routes (variable) |
+---------------------------------------------------------+ +---------------------------------------------------------+
The use and the meaning of these fields are as follows: The use and the meaning of these fields are as follows:
Address Family Identifier (AFI): Address Family Identifier (AFI):
This field in combination with the Subsequent Address Family This field in combination with the Subsequent Address Family
Identifier field identifies the semantics associated with the Identifier field identifies the set of Network Layer protocols
Network Layer Reachability Information (NLRI) that follows. to which the address carried in the Next Hop field must belong,
the way in which the address of the next hop is encoded, and
the semantics of the Network Layer Reachability Information
that follows. If the Next Hop is allowed to be from more than
one Network Layer protocol, the encoding of the Next Hop MUST
provide a way to determine its Network Layer protocol.
Presently defined values for the Address Family Identifier Presently defined values for the Address Family Identifier
field are specified in RFC1700 (see the Address Family Numbers field are specified in the IANA's Address Family Numbers
section). registry [IANA-AF].
Subsequent Address Family Identifier (SAFI): Subsequent Address Family Identifier (SAFI):
This field in combination with the Address Family Identifier This field in combination with the Address Family Identifier
field identifies the semantics associated with the Network field identifies the set of Network Layer protocols to which
Layer Reachability Information (NLRI) that follows. the address carried in the Next Hop must belong, the way in
which the address of the next hop is encoded, and the semantics
of the Network Layer Reachability Information that follows. If
the Next Hop is allowed to be from more than one Network Layer
protocol, the encoding of the Next Hop MUST provide a way to
determine its Network Layer protocol.
Withdrawn Routes Network Layer Reachability Information: Withdrawn Routes Network Layer Reachability Information:
A variable length field that lists NLRI for the routes that are A variable-length field that lists NLRI for the routes that are
being withdrawn from service. The semantics of NLRI is being withdrawn from service. The semantics of NLRI is
identified by a combination of <AFI, SAFI> carried in the identified by a combination of <AFI, SAFI> carried in the
attribute. attribute.
When the Subsequent Address Family Identifier field is set to When the Subsequent Address Family Identifier field is set to
one of the values defined in this document, each NLRI is one of the values defined in this document, each NLRI is
encoded as specified in the "NLRI encoding" section of this encoded as specified in the "NLRI encoding" section of this
document. document.
An UPDATE message that contains the MP_UNREACH_NLRI is not required An UPDATE message that contains the MP_UNREACH_NLRI is not required
to carry any other path attributes. to carry any other path attributes.
5. NLRI encoding 5. NLRI Encoding
The Network Layer Reachability information is encoded as one or more The Network Layer Reachability information is encoded as one or more
2-tuples of the form <length, prefix>, whose fields are described 2-tuples of the form <length, prefix>, whose fields are described
below: below:
+---------------------------+ +---------------------------+
| Length (1 octet) | | Length (1 octet) |
+---------------------------+ +---------------------------+
| Prefix (variable) | | Prefix (variable) |
+---------------------------+ +---------------------------+
The use and the meaning of these fields are as follows: The use and the meaning of these fields are as follows:
a) Length: a) Length:
The Length field indicates the length in bits of the address The Length field indicates the length, in bits, of the address
prefix. A length of zero indicates a prefix that matches all prefix. A length of zero indicates a prefix that matches all (as
(as specified by the address family) addresses (with prefix, specified by the address family) addresses (with prefix, itself,
itself, of zero octets). of zero octets).
b) Prefix: b) Prefix:
The Prefix field contains an address prefix followed by enough The Prefix field contains an address prefix followed by enough
trailing bits to make the end of the field fall on an octet trailing bits to make the end of the field fall on an octet
boundary. Note that the value of trailing bits is irrelevant. boundary. Note that the value of trailing bits is irrelevant.
6. Subsequent Address Family Identifier 6. Subsequent Address Family Identifier
This document defines the following values for the Subsequent Address This document defines the following values for the Subsequent Address
skipping to change at line 290 skipping to change at page 8, line 7
forwarding forwarding
2 - Network Layer Reachability Information used for multicast 2 - Network Layer Reachability Information used for multicast
forwarding forwarding
An implementation MAY support all, some, or none of the Subsequent An implementation MAY support all, some, or none of the Subsequent
Address Family Identifier values defined in this document. Address Family Identifier values defined in this document.
7. Error Handling 7. Error Handling
If a BGP speaker receives from a neighbor an Update message that If a BGP speaker receives from a neighbor an UPDATE message that
contains the MP_REACH_NLRI or MP_UNREACH_NLRI attribute, and the contains the MP_REACH_NLRI or MP_UNREACH_NLRI attribute, and if the
speaker determines that the attribute is incorrect, the speaker MUST speaker determines that the attribute is incorrect, the speaker MUST
delete all the BGP routes received from that neighbor whose AFI/SAFI delete all the BGP routes received from that neighbor whose AFI/SAFI
is the same as the one carried in the incorrect MP_REACH_NLRI or is the same as the one carried in the incorrect MP_REACH_NLRI or
MP_UNREACH_NLRI attribute. For the duration of the BGP session over MP_UNREACH_NLRI attribute. For the duration of the BGP session over
which the Update message was received, the speaker then SHOULD ignore which the UPDATE message was received, the speaker then SHOULD ignore
all the subsequent routes with that AFI/SAFI received over that all the subsequent routes with that AFI/SAFI received over that
session. session.
In addition, the speaker MAY terminate the BGP session over which the In addition, the speaker MAY terminate the BGP session over which the
Update message was received. The session SHOULD be terminated with UPDATE message was received. The session SHOULD be terminated with
the Notification message code/subcode indicating "Update Message the Notification message code/subcode indicating "UPDATE Message
Error"/"Optional Attribute Error". Error"/"Optional Attribute Error".
8. Use of BGP Capability Advertisement 8. Use of BGP Capability Advertisement
A BGP speaker that uses Multiprotocol Extensions SHOULD use the A BGP speaker that uses Multiprotocol Extensions SHOULD use the
Capability Advertisment procedures [BGP-CAP] to determine whether the Capability Advertisement procedures [BGP-CAP] to determine whether
speaker could use Multiprotocol Extensions with a particular peer. the speaker could use Multiprotocol Extensions with a particular
peer.
The fields in the Capabilities Optional Parameter are set as follows. The fields in the Capabilities Optional Parameter are set as follows.
The Capability Code field is set to 1 (which indicates Multiprotocol The Capability Code field is set to 1 (which indicates Multiprotocol
Extensions capabilities). The Capability Length field is set to 4. Extensions capabilities). The Capability Length field is set to 4.
The Capability Value field is defined as: The Capability Value field is defined as:
0 7 15 23 31 0 7 15 23 31
+-------+-------+-------+-------+ +-------+-------+-------+-------+
| AFI | Res. | SAFI | | AFI | Res. | SAFI |
+-------+-------+-------+-------+ +-------+-------+-------+-------+
The use and meaning of this field is as follow: The use and meaning of this field is as follow:
AFI - Address Family Identifier (16 bit), encoded the same way AFI - Address Family Identifier (16 bit), encoded the same way as
as in the Multiprotocol Extensions in the Multiprotocol Extensions
Res. - Reserved (8 bit) field. SHOULD be set to 0 by the sender Res. - Reserved (8 bit) field. SHOULD be set to 0 by the sender
and ignored by the receiver. and ignored by the receiver.
SAFI - Subsequent Address Family Identifier (8 bit), encoded Note that not setting the field value to 0 may create issues
the same way as in the Multiprotocol Extensions. for a receiver not ignoring the field. In addition, this
definition is problematic if it is ever attempted to redefine
the field.
SAFI - Subsequent Address Family Identifier (8 bit), encoded the
same way as in the Multiprotocol Extensions.
A speaker that supports multiple <AFI, SAFI> tuples includes them as A speaker that supports multiple <AFI, SAFI> tuples includes them as
multiple Capabilities in the Capabilities Optional Parameter. multiple Capabilities in the Capabilities Optional Parameter.
To have a bi-directional exchange of routing information for a To have a bi-directional exchange of routing information for a
particular <AFI, SAFI> between a pair of BGP speakers, each such particular <AFI, SAFI> between a pair of BGP speakers, each such
speaker MUST advertise to the other (via the Capability Advertisement speaker MUST advertise to the other (via the Capability Advertisement
mechanism) the capability to support that particular <AFI, SAFI> mechanism) the capability to support that particular <AFI, SAFI>
routes. route.
9. IANA Considerations 9. IANA Considerations
As specified in this document, the MP_REACH_NLRI and MP_UNREACH_NLRI As specified in this document, the MP_REACH_NLRI and MP_UNREACH_NLRI
attributes contain the Subsequence Address Family Identifier (SAFI) attributes contain the Subsequence Address Family Identifier (SAFI)
field. The SAFI name space is defined in this document. The IANA will field. The SAFI name space is defined in this document. The IANA
maintain and register values for the SAFI namespace as follows: registered and maintains values for the SAFI namespace as follows:
- SAFI values 1 and 2 are assigned in this document. - SAFI values 1 and 2 are assigned in this document.
- SAFI value 3 is reserved. It was assigned by RFC 2858 for a use - SAFI value 3 is reserved. It was assigned by RFC 2858 for a use
that was never fully implemented, so is deprecated by this that was never fully implemented, so it is deprecated by this
document. document.
- SAFI values 5 through 63 are to be assigned by IANA using either - SAFI values 5 through 63 are to be assigned by IANA using either
the Standards Action process defined in [RFC2434], or the Early the Standards Action process, defined in [RFC2434], or the Early
IANA Allocation process defined in [RFC4020]. IANA Allocation process, defined in [RFC4020].
- SAFI values 67 through 127 are to be assigned by IANA, using the - SAFI values 67 through 127 are to be assigned by IANA, using the
"First Come First Served" policy defined in RFC2434. "First Come First Served" policy, defined in RFC 2434.
- SAFI values 0 and 255 are reserved. - SAFI values 0 and 255 are reserved.
- SAFI values 128 through 240 are part of the previous "private - SAFI values 128 through 240 are part of the previous "private
use" range. Of this space, allocations which are currently in use use" range. At the time of approval of this document, the
are to be recognized by IANA. Unused values, namely 130, 131, 135 unused values were provided to IANA by the Routing Area
through 139, and 141 through 240 should be considered reserved, in Director. These unused values, namely, 130, 131, 135 through
order to avoid conflicts. 139, and 141 through 240, are considered reserved in order to
avoid conflicts.
- SAFI values 241 through 254 are for "private use", and values in - SAFI values 241 through 254 are for "private use", and values in
this range are not to be assigned by IANA. this range are not to be assigned by IANA.
10. Comparison with RFC2858 10. Comparison with RFC2858
This document makes the use of the next hop information consistent This document makes the use of the next hop information consistent
with the information carried in the NEXT_HOP BGP path attribute. with the information carried in the NEXT_HOP BGP path attribute.
This document removes the definition of SAFI 3, and deprecates SAFI This document removes the definition of SAFI 3 and deprecates SAFI 3.
3.
This document changes partitioning of the SAFI space. Specifically, This document changes partitioning of the SAFI space. Specifically,
in RFC2858 SAFI values 128 through 240 were part of the "private use" in RFC 2858 SAFI values 128 through 240 were part of the "private
range. This document specifies that of this range, allocations which use" range. This document specifies that of this range, allocations
are currently in use are to be recognized by IANA, and that unused that are currently in use are to be recognized by IANA, and that
values, namely 130, 131, 135 through 139, and 141 through 240 should unused values, namely 130, 131, 135 through 139, and 141 through 240,
be considered reserved. should be considered reserved.
This document renames the Number of SNPAs field to Reserved, and This document renames the Number of SNPAs field to Reserved and
removes the rest of the SNPA-related information from the removes the rest of the SNPA-related information from the
MP_REACH_NLRI attribute. MP_REACH_NLRI attribute.
11. Comparison with RFC2283 11. Comparison with RFC2283
This document restricts the MP_REACH_NLRI attribute to carry only a This document restricts the MP_REACH_NLRI attribute to carry only a
single instance of <AFI, SAFI, Next Hop Information, ...>. single instance of <AFI, SAFI, Next Hop Information, ...>.
This document restricts the MP_UNREACH_NLRI attribute to carry only a This document restricts the MP_UNREACH_NLRI attribute to carry only a
single instance of <AFI, SAFI, ...>. single instance of <AFI, SAFI, ...>.
This document clarifies handling of an UPDATE message that carries no This document clarifies handling of an UPDATE message that carries no
NLRI, other than the one encoded in the MP_REACH_NLRI attribute. NLRI, other than the one encoded in the MP_REACH_NLRI attribute.
This document clarifies error handling in the presence of This document clarifies error handling in the presence of
MP_REACH_NLRI or MP_UNREACH_NLRI attributes. MP_REACH_NLRI or MP_UNREACH_NLRI attributes.
This document specifies the use of BGP Capabilities Advertisements in This document specifies the use of BGP Capabilities Advertisements in
conjunction with Multi-protocol extensions. conjunction with multi-protocol extensions.
Finally, this document includes the "IANA Consideration" Section. Finally, this document includes the "IANA Consideration" section.
12. Security Considerations 12. 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. inherent in the existing BGP.
13. Intellectual Property Considerations 13. Acknowledgements
This section is taken from Section 5 of RFC 3668.
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.
14. Copyright Notice
Copyright (C) The Internet Society (2006).
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 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.
15. Acknowledgements
The authors would like to thank members of the IDR Working Group for The authors would like to thank members of the IDR Working Group for
their review and comments. their review and comments.
16. Normative References 14. Normative References
[BGP-CAP] "Capabilities Advertisement with BGP-4", R. Chandra, J. [BGP-CAP] Chandra, R. and J. Scudder, "Capabilities Advertisement
with BGP-4", RFC 3392, November 2002.
[BGP-4] Rekhter, Y., and T. Li, "A Border Gateway Protocol 4 [BGP-4] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway
(BGP-4)", RFC 1771, March 1995. Protocol 4 (BGP-4)", RFC 4271, January 2006.
[RFC1700] "Assigned Numbers", J. Reynolds, J. Postel, RFC1700, [IANA-AF] "Address Family Numbers", Reachable from
October 1994 (see also http://www.iana.org/iana/assignments.html) http://www.iana.org/numbers.html
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2434] Narten, T., Alvestrand, H., "Guidelines for Writing an IANA [RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an
Considerations Section in RFCs", RFC2434, October 1998 IANA Considerations Section in RFCs", BCP 26, RFC 2434,
October 1998.
[RFC4020] "Early IANA Allocation of Standards Track Code Points", K. [RFC4020] Kompella, K. and A. Zinin, "Early IANA Allocation of
Kompella, A. Zinin, BCP0100, RFC 4020, February 2005. Standards Track Code Points", BCP 100, RFC 4020, February
2005.
17. Author Information Authors' Addresses
Tony Bates Tony Bates
Cisco Systems, Inc. Cisco Systems, Inc.
email: tbates@cisco.com EMail: tbates@cisco.com
Ravi Chandra Ravi Chandra
Sonoa Systems Sonoa Systems
e-mail: rchandra@sonoasystems.com EMail: rchandra@sonoasystems.com
Dave Katz Dave Katz
Juniper Networks, Inc. Juniper Networks, Inc.
email: dkatz@juniper.com EMail: dkatz@juniper.net
Yakov Rekhter Yakov Rekhter
Juniper Networks, Inc. Juniper Networks, Inc.
email: yakov@juniper.com EMail: yakov@juniper.net
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