draft-ietf-grow-collection-communities-02.txt   draft-ietf-grow-collection-communities-03.txt 
INTERNET-DRAFT D. Meyer INTERNET-DRAFT D. Meyer
draft-ietf-grow-collection-communities-02.txt draft-ietf-grow-collection-communities-03.txt
Category Best Current Practice Category Best Current Practice
Expires: July 2004 January 2004 Expires: September 2004 March 2004
BGP Communities for Data Collection BGP Communities for Data Collection
<draft-ietf-grow-collection-communities-02.txt> <draft-ietf-grow-collection-communities-03.txt>
Status of this Document Status of this Document
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 1, line 32 skipping to change at page 1, line 32
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt http://www.ietf.org/ietf/1id-abstracts.txt
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.
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].
This document is a product of the GROW WG. Comments should be This document is a product of the GROW WG. Comments should be
addressed to the authors, or the mailing list at addressed to the authors, or the mailing list at grow@lists.uoregon.edu.
grow@lists.uoregon.edu.
Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved. Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract Abstract
BGP communities (RFC 1997) are used by service providers for many BGP communities (RFC 1997) are used by service providers for many
purposes, including tagging of customer, peer, and geographically purposes, including tagging of customer, peer, and geographically
originated routes. Such tagging is typically used to control the originated routes. Such tagging is typically used to control the
skipping to change at page 3, line 13 skipping to change at page 3, line 13
route collectors. route collectors.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Peers and Peering . . . . . . . . . . . . . . . . . . . . . 5 2.1. Peers and Peering . . . . . . . . . . . . . . . . . . . . . 5
2.2. Customer Routes . . . . . . . . . . . . . . . . . . . . . . 5 2.2. Customer Routes . . . . . . . . . . . . . . . . . . . . . . 5
2.3. Peer Routes . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3. Peer Routes . . . . . . . . . . . . . . . . . . . . . . . . 5
2.4. Internal Routes . . . . . . . . . . . . . . . . . . . . . . 5 2.4. Internal Routes . . . . . . . . . . . . . . . . . . . . . . 5
2.5. Internal More Specific Routes . . . . . . . . . . . . . . . 5 2.5. Internal More Specific Routes . . . . . . . . . . . . . . . 6
2.6. Special Purpose Routes. . . . . . . . . . . . . . . . . . . 6 2.6. Special Purpose Routes. . . . . . . . . . . . . . . . . . . 6
2.7. Upstream Routes . . . . . . . . . . . . . . . . . . . . . . 6 2.7. Upstream Routes . . . . . . . . . . . . . . . . . . . . . . 6
2.8. National Routes . . . . . . . . . . . . . . . . . . . . . . 6 2.8. National Routes . . . . . . . . . . . . . . . . . . . . . . 6
2.9. Regional Routes . . . . . . . . . . . . . . . . . . . . . . 6 2.9. Regional Routes . . . . . . . . . . . . . . . . . . . . . . 6
3. RFC 1997 Community Encoding and Values . . . . . . . . . . . . 7 3. RFC 1997 Community Encoding and Values . . . . . . . . . . . . 7
3.1. Community Values for BGP Data Collection. . . . . . . . . . 7 3.1. Community Values for BGP Data Collection. . . . . . . . . . 7
4. Extended Communities . . . . . . . . . . . . . . . . . . . . . 9 4. Extended Communities . . . . . . . . . . . . . . . . . . . . . 9
4.1. Four-octet AS specific extended communities . . . . . . . . 10 4.1. Four-octet AS specific extended communities . . . . . . . . 10
5. Intellectual Property. . . . . . . . . . . . . . . . . . . . . 10 5. Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . 10
6. Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . 11 6. Security Considerations. . . . . . . . . . . . . . . . . . . . 12
7. Security Considerations. . . . . . . . . . . . . . . . . . . . 12 6.1. Total Path Attribute Length . . . . . . . . . . . . . . . . 12
7.1. Total Path Attribute Length . . . . . . . . . . . . . . . . 12 7. IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 12
8. IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 12 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 8.1. Normative References. . . . . . . . . . . . . . . . . . . . 13
9.1. Normative References. . . . . . . . . . . . . . . . . . . . 13 8.2. Informative References. . . . . . . . . . . . . . . . . . . 13
9.2. Informative References. . . . . . . . . . . . . . . . . . . 13 9. Author's Addresses . . . . . . . . . . . . . . . . . . . . . . 14
10. Author's Addresses. . . . . . . . . . . . . . . . . . . . . . 14 10. Full Copyright Statement. . . . . . . . . . . . . . . . . . . 14
11. Full Copyright Statement. . . . . . . . . . . . . . . . . . . 14 11. Intellectual Property . . . . . . . . . . . . . . . . . . . . 15
12. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction 1. Introduction
BGP communities [RFC1997] are used by service providers for many BGP communities [RFC1997] are used by service providers for many
purposes, including tagging of customer, peer, and geographically purposes, including tagging of customer, peer, and geographically
originated routes. Such tagging is typically used to control the originated routes. Such tagging is typically used to control the
scope of redistribution of routes within a providers network, and to scope of redistribution of routes within a providers network, and to
it's customers and peers. Communities are also used for a wide its customers and peers. Communities are also used for a wide variety
variety of other applications, such as allowing customers to set of other applications, such as allowing customers to set attributes
attributes such as LOCAL_PREF [RFC1771] by sending appropriate such as LOCAL_PREF [RFC1771] by sending appropriate communities to
communities to their service provider. Other applications include their service provider. Other applications include signaling various
signaling various types of VPNs (e.g., VPLS [VPLS]), and carrying types of VPNs (e.g., VPLS [VPLS]), and carrying link bandwidth for
link bandwidth for traffic engineering applications [EXTCOMM]. traffic engineering applications [EXTCOMM].
With the advent of large scale BGP data collection [RIS,ROUTEVIEWS] With the advent of large scale BGP data collection [RIS,ROUTEVIEWS]
(and associated research), it has become clear that the geographical (and associated research), it has become clear that the geographical
and topological information, as well as the relationship the provider and topological information, as well as the relationship the provider
has to the source of a route (e.g., transit, peer, or customer), has to the source of a route (e.g., transit, peer, or customer),
carried in such communities is essential for a deeper understanding carried in such communities is essential for a deeper understanding
of the global routing system. This document defines standard of the global routing system. This document defines standard
communities for export to BGP route collectors. These communities are communities for export to BGP route collectors. These communities
not (necessarily) intended for internal use by service providers. represent a significant part of information carried by service
Rather, they are meant to mirror the information that many service providers as of this writing, and as such could be useful for
providers carry today, and to be a standardized representation of internal use by service providers. However, such use is beyond the
that information. scope of this memo. Finally, those involved in BGP data analysis are
encouraged to verify with their data sources as to which peers
implement this scheme (as there is a large amount of existing data as
well as many legacy peerings).
The remainder of this document is organized as follows. Section 2 The remainder of this document is organized as follows. Section 2
provides both the definition of terms used as well as the semantics provides both the definition of terms used as well as the semantics
of the communities used for BGP data collection, and section 3 of the communities used for BGP data collection, and section 3
defines the corresponding encodings for RFC 1997 [RFC1997] defines the corresponding encodings for RFC 1997 [RFC1997]
communities. Finally, section 4 defines the encodings for use with communities. Finally, section 4 defines the encodings for use with
extended communities [EXTCOMM]. extended communities [EXTCOMM].
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].
2. Definitions 2. Definitions
In this section, we define the terms used and the categories of In this section, we define the terms used and the categories of
routes that may be tagged with communities. This tagging is often routes that may be tagged with communities. This tagging is often
referred to coloring, and we refer to a route's "color" as its referred to coloring, and we refer to a route's "color" as its
community value. The categories defined here are loosely modeled on community value. The categories defined here are loosely modeled on
those described in [WANG] and [HUSTON]. those described in [WANG] and [HUSTON].
2.1. Peers and Peering 2.1. Peers and Peering
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2.4. Internal Routes 2.4. Internal Routes
Internal routes are those routes that a service provider originates Internal routes are those routes that a service provider originates
and passes to its peers and customers. These routes are frequently and passes to its peers and customers. These routes are frequently
taken out of the address space allocated to a provider. taken out of the address space allocated to a provider.
2.5. Internal More Specific Routes 2.5. Internal More Specific Routes
Internal more specific routes are those routes which are frequently Internal more specific routes are those routes which are frequently
used for circuit balancing purposes, IGP route reduction, and also used for circuit load balancing purposes, IGP route reduction, and
may correspond to customer services which are not visible outside the also may correspond to customer services which are not visible
service provider's network. Internal more specific routes are not outside the service provider's network. Internal more specific routes
exported to any external peer. are not exported to any external peer.
2.6. Special Purpose Routes 2.6. Special Purpose Routes
Special purpose routes are those routes which do not fall into any of Special purpose routes are those routes which do not fall into any of
the other classes described here. In those cases in which such routes the other classes described here. In those cases in which such routes
need to be distinguished, a service provider may color such routes need to be distinguished, a service provider may color such routes
with a unique value. Examples of special purpose routes include with a unique value. Examples of special purpose routes include
anycast routes, and routes for overlay networks. anycast routes, and routes for overlay networks.
2.7. Upstream Routes 2.7. Upstream Routes
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AS in one region, and that same AS is a customer in another region. AS in one region, and that same AS is a customer in another region.
This mandates use of regional routing, including community attributes This mandates use of regional routing, including community attributes
set by the network in question to allow easy discrimination among set by the network in question to allow easy discrimination among
regional routes. For example, service providers may treat a route set regional routes. For example, service providers may treat a route set
received from another service provider in Europe differently than the received from another service provider in Europe differently than the
same route set received in North America, as it is common practice to same route set received in North America, as it is common practice to
sell transit in one region while peering in the other. sell transit in one region while peering in the other.
3. RFC 1997 Community Encoding and Values 3. RFC 1997 Community Encoding and Values
In this section we provide standardized RFC 1997 [RFC1997] community In this section we provide RFC 1997 [RFC1997] community values for
values for the categories described above. RFC 1997 communities the categories described above. RFC 1997 communities encoded as BGP
encoded as BGP Type Code 8, and are treated as 32 bit values ranging Type Code 8, and are treated as 32 bit values ranging from 0x0000000
from 0x0000000 through 0xFFFFFFF. The values 0x0000000 through through 0xFFFFFFF. The values 0x0000000 through 0x0000FFFF and
0x0000FFFF and 0xFFFF0000 through 0xFFFFFFFF are reserved. 0xFFFF0000 through 0xFFFFFFFF are reserved.
The best current practice among service providers is to use the high The best current practice among service providers is to use the high
order two octets to represent the providers AS number, and the low order two octets to represent the providers AS number, and the low
order two octets to represent the classification of the route, as order two octets to represent the classification of the route, as
depicted below: depicted below:
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| <AS> | <Value> | | <AS> | <Value> |
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<CC> = Fiji Islands Country Code = 242 = 0011110010 <CC> = Fiji Islands Country Code = 242 = 0011110010
so that the low order 16 bits look like 001000011110010 = 0x10F2. so that the low order 16 bits look like 001000011110010 = 0x10F2.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0x2A7C | 0x10F2 | | 0x2A7C | 0x10F2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note that a configuration language might have allow the specification Note that a configuration language might allow the specification of
of this community as 10876:4338 (0x1F2 == 4338 decimal). this community as 10876:4338 (0x1F2 == 4338 decimal).
Finally, note that these categories are not intended to be mutually Finally, note that these categories are not intended to be mutually
exclusive, and multiple communities can be attached where exclusive, and multiple communities can be attached where
appropriate. appropriate.
4. Extended Communities 4. Extended Communities
In some cases, the encoding described in section 3.1 may clash with a In some cases, the encoding described in section 3.1 may clash with a
service provider's existing community assignments. Extended service provider's existing community assignments. Extended
communities [EXTCOMM] provide a convenient mechanism that can be used communities [EXTCOMM] provide a convenient mechanism that can be used
skipping to change at page 10, line 4 skipping to change at page 10, line 4
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0x00 | Sub-Type | Global Administrator | | 0x00 | Sub-Type | Global Administrator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Administrator | | Local Administrator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The two-octet AS specific extended community attribute encodes the The two-octet AS specific extended community attribute encodes the
service provider's two octet Autonomous System number assigned by service provider's two octet Autonomous System number (as assigned by
IANA in the Global Administrator field, and the Local Administrator an Internet Routing Registry) in the Global Administrator field, and
field may encode any information. the Local Administrator field may encode any information.
This document assigns Sub-Type 0x05 for BGP data collection, and This document assigns Sub-Type 0x05 for BGP data collection, and
specifies that the <Value> field, as defined in section 3.1, is specifies that the <Value> field, as defined in section 3.1, is
carried in the low order octets of the Local Administrator field. The carried in the low order octets of the Local Administrator field. The
two high order octets of the Local Administrator field are reserved, two high order octets of the Local Administrator field are reserved,
and are set to 0x00 when sending and ignored upon receipt. and are set to 0x00 when sending and ignored upon receipt.
For example, the extended community encoding for 10876:4338 For example, the extended community encoding for 10876:4338
(representing a terrestrial national route in AS 10876 from the Fiji (representing a terrestrial national route in AS 10876 from the Fiji
Islands) would be: Islands) would be:
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0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0x02 | 0x05 | Global Administrator | | 0x02 | 0x05 | Global Administrator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Global Administrator (cont.) | 0x10F2 | | Global Administrator (cont.) | 0x10F2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
In this case, the 4 octet Global Administrator sub-field contains a In this case, the 4 octet Global Administrator sub-field contains a
4-octets Autonomous System number assigned by the IANA. 4-octets Autonomous System number assigned by the IANA.
5. Intellectual Property 5. Acknowledgments
The IETF takes no position regarding the validity or scope of any
intellectual property 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; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11 [RFC2028].
Copies of claims of rights made available for publication 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 implementors or users of this
specification can be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
6. Acknowledgments
The community encoding described in this document germinated from an The community encoding described in this document germinated from an
interesting suggestion from Akira Kato at WIDE. In particular, the interesting suggestion from Akira Kato at WIDE. In particular, the
idea would be to use the collection community values to select paths idea would be to use the collection community values to select paths
that would result in (hopefully) more efficient access to various that would result in (hopefully) more efficient access to various
services. For example, in the case of RFC 3258 [RFC3258] based DNS services. For example, in the case of RFC 3258 [RFC3258] based DNS
anycast service, BGP routers may see multiple paths to the same anycast service, BGP routers may see multiple paths to the same
prefix, and others might be coming from the same origin with prefix, and others might be coming from the same origin with
different paths, but others might be from different region/country different paths, but others might be from different region/country
(with the same origin AS). (with the same origin AS).
Joe Abley, Randy Bush, Sean Donelan, Xenofontas Dimitropoulos, Vijay Joe Abley, Randy Bush, Sean Donelan, Xenofontas Dimitropoulos, Vijay
Gill, John Heasley, Geoff Huston, Steve Huter, Olivier Marce, Ryan Gill, John Heasley, Geoff Huston, Steve Huter, Olivier Marce, Ryan
McDowell, Rob Rockell, Rob Thomas, and Patrick Verkaik all made many McDowell, Rob Rockell, Rob Thomas, Pekka Savola, and Patrick Verkaik
insightful comments on early versions of this draft. Henk Uijterwaal all made many insightful comments on early versions of this draft.
suggested the use of the ISO-3166-2 country codes. Henk Uijterwaal suggested the use of the ISO-3166-2 country codes.
7. Security Considerations 6. Security Considerations
While this document introduces no additional security considerations While this document introduces no additional security considerations
into the BGP protocol, the information contained in the communities into the BGP protocol, the information contained in the communities
defined in this document may in some cases reveal network structure defined in this document may in some cases reveal network structure
that was not previously visible outside the provider's network. As a that was not previously visible outside the provider's network. As a
result, care should be taken when exporting such communities to route result, care should be taken when exporting such communities to route
collectors. Finally, routes exported to a route collector SHOULD also collectors. Finally, routes exported to a route collector should also
be tagged with the NO_EXPORT community (0xFFFFFF01). be tagged with the NO_EXPORT community (0xFFFFFF01).
7.1. Total Path Attribute Length 6.1. Total Path Attribute Length
The communities described in this document are intended for use on The communities described in this document are intended for use on
egress to a route collector. Hence an operator may choose to egress to a route collector. Hence an operator may choose to
overwrite its internal communities with the values specified in this overwrite its internal communities with the values specified in this
document when exporting routes to a route collector. However, document when exporting routes to a route collector. However,
operators should in general ensure that the behavior of their BGP operators should in general ensure that the behavior of their BGP
implementation is well-defined when the addition of an attribute implementation is well-defined when the addition of an attribute
causes a PDU to exceed 4096 octets. For example, since it is common causes a PDU to exceed 4096 octets. For example, since it is common
practice to use community attributes to implement policy (among other practice to use community attributes to implement policy (among other
functionality such as allowing customers to set attributes such as functionality such as allowing customers to set attributes such as
LOCAL_PREF), the behavior of an implementation when the attribute LOCAL_PREF), the behavior of an implementation when the attribute
space overflows is crucial. Among other behaviors, an implementation space overflows is crucial. Among other behaviors, an implementation
might usurp the intended attribute data or otherwise cause might usurp the intended attribute data or otherwise cause
indeterminate failures. These behaviors can result in unanticipated indeterminate failures. These behaviors can result in unanticipated
community attribute sets, and hence result in unintended policy community attribute sets, and hence result in unintended policy
implications. implications.
8. IANA Considerations 7. IANA Considerations
This document assigns a new Sub-Type for the AS specific extended This document assigns a new Sub-Type for the AS specific extended
community type. In particular, the IANA should assign Sub-type 0x05, community type. In particular, the IANA should assign Sub-type 0x05,
using the "First Come First Served" policy defined in RFC 2434 using the "First Come First Served" policy defined in RFC 2434
[RFC2434], for the Sub-Type defined in Section 4. This corresponds to [RFC2434], for the Sub-Type defined in Section 4. This corresponds to
a Type Field value of 0x0005. a Type Field value of 0x0005.
9. References 8. References
9.1. Normative References 8.1. Normative References
[EXTCOMM] Sangali, S., D. Tappan and Y. Rekhter, "BGP [EXTCOMM] Sangali, S., D. Tappan and Y. Rekhter, "BGP Extended Communities
Extended Communities Attribute", Attribute", draft-ietf-idr-bgp-ext-communities-06.txt,
draft-ietf-idr-bgp-ext-communities-06.txt,
Work in Progress. Work in Progress.
[HOUSTON] Huston, G., "Interconnection, Peering, and
Settlements",
http://www.isoc.org/inet99/proceedings/1e/1e_1.htm
[ISO-3166-2] http://www.iso.org/iso/en/prods-services/iso3166ma/index.html [ISO-3166-2] http://www.iso.org/iso/en/prods-services/iso3166ma/index.html
[RIS] "Routing Information Service", http://www.ripe.net/ris
[RIS-ISO-3166] ftp://ftp.ripe.net/iso3166-countrycodes.txt [RIS-ISO-3166] ftp://ftp.ripe.net/iso3166-countrycodes.txt
[ROUTEVIEWS] "The Routeviews Project", http://www.routeviews.org
[RFC1771] Rekhter, Y., and T. Li (Editors), "A Border [RFC1771] Rekhter, Y., and T. Li (Editors), "A Border
Gateway Protocol (BGP-4)", RFC 1771, March, Gateway Protocol (BGP-4)", RFC 1771, March,
1995. 1995.
[RFC1997] Chandra, R. and P. Traina, "BGP Communities [RFC1997] Chandra, R. and P. Traina, "BGP Communities
Attribute", RFC 1997, August, 1996. Attribute", RFC 1997, August, 1996.
[VLPS] Kompella, K., et. al., "Virtual Private LAN 8.2. Informative References
Service", draft-ietf-l2vpn-vpls-bgp-00.txt,
Work in Progress.
[WANG] Wang, F. and L. Gao, "Inferring and Characterizing
Internet Routing Policies", ACM SIGCOMM Internet
Measurement Conference 2003.
9.2. Informative References [HUSTON] Huston, G., "Interconnection, Peering, and Settlements",
http://www.isoc.org/inet99/proceedings/1e/1e_1.htm
[RFC2119] Bradner, S., "Key words for use in RFCs to [RFC2119] Bradner, S., "Key words for use in RFCs to
Indicate Requirement Levels", RFC 2119, March, Indicate Requirement Levels", RFC 2119, March,
1997. 1997.
[RFC2026] Bradner, S., "The Internet Standards Process -- [RFC2026] Bradner, S., "The Internet Standards Process --
Revision 3", RFC 2026/BCP 9, October, 1996. Revision 3", RFC 2026/BCP 9, October, 1996.
[RFC2028] Hovey, R. and S. Bradner, "The Organizations [RFC2028] Hovey, R. and S. Bradner, "The Organizations
Involved in the IETF Standards Process", RFC Involved in the IETF Standards Process", RFC
2028/BCP 11, October, 1996. 2028/BCP 11, October, 1996.
[RFC2434] Narten, T., and H. Alvestrand, "Guidelines for [RFC2434] Narten, T., and H. Alvestrand, "Guidelines for
Writing an IANA Considerations Section in RFCs", Writing an IANA Considerations Section in RFCs",
RFC 2434/BCP 26, October 1998. RFC 2434/BCP 26, October 1998.
[RFC3258] Hardie, T., "Distributing Authoritative Name [RFC3258] Hardie, T., "Distributing Authoritative Name
Servers via Shared Unicast Addresses", RFC 3258, Servers via Shared Unicast Addresses", RFC 3258,
April, 2002. April, 2002.
10. Author's Addresses [RIS] "Routing Information Service", http://www.ripe.net/ris
[ROUTEVIEWS] "The Routeviews Project", http://www.routeviews.org
[VPLS] Kompella, K., et. al., "Virtual Private LAN
Service", draft-ietf-l2vpn-vpls-bgp-00.txt,
Work in Progress.
[WANG] Wang, F. and L. Gao, "Inferring and Characterizing
Internet Routing Policies", ACM SIGCOMM Internet
Measurement Conference 2003.
9. Author's Addresses
D. Meyer D. Meyer
Email: dmm@1-4-5.net Email: dmm@1-4-5.net
11. Full Copyright Statement 10. Full Copyright Statement
Copyright (C) The Internet Society (2004). All Rights Reserved. Copyright (C) The Internet Society (2004). 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 translations of it may be copied and furnished to This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of Internet organizations, except as needed for the purpose of
skipping to change at line 525 skipping to change at page 15, line 14
The limited permissions granted above are perpetual and will not be The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns. revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
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BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
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12. Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
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