< draft-ietf-idr-bgp-ext-communities-08.txt   draft-ietf-idr-bgp-ext-communities-09.txt >
Network Working Group Srihari R. Sangli (Cisco Systems) Network Working Group Srihari R. Sangli (Cisco Systems)
Internet Draft Daniel Tappan (Cisco Systems) Internet Draft Daniel Tappan (Cisco Systems)
Expiration Date: August 2005 Yakov Rekhter (Juniper Networks) Expiration Date: January 2006 Yakov Rekhter (Juniper Networks)
BGP Extended Communities Attribute BGP Extended Communities Attribute
draft-ietf-idr-bgp-ext-communities-08.txt draft-ietf-idr-bgp-ext-communities-09.txt
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and any of which I become aware will be disclosed, in accordance with have been or will be disclosed, and any of which he or she becomes
RFC 3668. aware will be disclosed, in accordance with Section 6 of BCP 79.
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Abstract Abstract
This document describes an extension to BGP-4 which may be used to This document describes the "extended community" BGP-4 attribute.
provide flexible control over the distribution of routing This attribute provides a mechanism for labeling information carried
information. in BGP-4. These labels can be used to control the distribution of
this information, or for other applications.
Specification of Requirements Specification of Requirements
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
1. Introduction 1. Introduction
The Extended Community Attribute provides two important enhancements The Extended Community Attribute provides two important enhancements
over the existing BGP Community Attribute: over the existing BGP Community Attribute [RFC1997]:
- It provides an extended range, ensuring that communities can be - It provides an extended range, ensuring that communities can be
assigned for a plethora of uses, without fear of overlap. assigned for a plethora of uses, without fear of overlap.
- The addition of a Type field provides structure for the - The addition of a Type field provides structure for the
community space. community space.
The addition of structure allows the usage of policy based on the The addition of structure allows the usage of policy based on the
application for which the community value will be used. For example, application for which the community value will be used. For example,
one can filter out all communities of a particular type, or allow one can filter out all communities of a particular type, or allow
only certain values for a particular type of community. It also only certain values for a particular type of community. It also
allows one to specify whether a particular community is transitive or allows one to specify whether a particular community is transitive or
non-transitive across Autonomous system boundary. Without structure, non-transitive across Autonomous system boundary. Without structure,
this can only be accomplished by explicitly enumerating all community this can only be accomplished by explicitly enumerating all community
values which will be denied or allowed and passed to BGP speakers in values which will be denied or allowed and passed to BGP speakers in
neighboring ASes based on the transitive property. neighboring ASes based on the transitive property.
2. BGP Extended Communities Attribute 2. BGP Extended Communities Attribute
The Extended Communities Attribute is a transitive optional BGP The Extended Communities Attribute is a transitive optional BGP
attribute, with the Type Code 16. The attribute consists of a set of attribute, with the Type Code 16. The attribute consists of a set of
"extended communities". All routes with the Extended Communities "extended communities". All routes with the Extended Communities
attribute belong to the communities listed in the attribute. attribute belong to the communities listed in the attribute.
Each Extended Community is encoded as an eight octet quantity, as Each Extended Community is encoded as an eight octet quantity, as
follows: follows:
- Type Field : 1 or 2 octets - Type Field : 1 or 2 octets
- Value Field : Remaining octets - Value Field : Remaining octets
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type high | Type low(*) | | | Type high | Type low(*) | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Value | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Value |
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*) Present for Extended types only, used for the Value field *) Present for Extended types only, used for the Value field
otherwise otherwise
skipping to change at page 4, line 4 skipping to change at page 3, line 14
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type high | Type low(*) | | | Type high | Type low(*) | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Value | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Value |
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*) Present for Extended types only, used for the Value field *) Present for Extended types only, used for the Value field
otherwise otherwise
Type Field: Type Field:
Two classes of Type Field are introduced: Regular type and Two classes of Type Field are introduced: Regular type and
Extended type. Extended type.
The size of Type Field for Regular types is 1 octet and the The size of Type Field for Regular types is 1 octet and the
size of the Type Field for Extended types is 2 octets. size of the Type Field for Extended types is 2 octets.
The value of the high-order octet of the Type Field determines The value of the high-order octet of the Type Field determines
if an extended community is a Regular type or an Extended type. if an extended community is a Regular type or an Extended type.
The class of a type (Regular or Extended) is not encoded in the
structure of the type itself. The class of a type is specified
in the document which defines the type and the IANA registry.
The high-order octet of the Type Field is as shown below: The high-order octet of the Type Field is as shown below:
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
|I|T| | |I|T| |
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
I - IANA authority bit I - IANA authority bit
Value 0: IANA assignable type using the "First Come First Value 0: IANA assignable type using the "First Come First
Serve" policy Serve" policy
Value 1: IANA assignable type using the IETF Consensus Value 1: Part of this Type Field space is for IANA
policy and experimental assignable types using either the Standard Action or the
Early IANA Allocation policy. The rest of this Type
Field space is for Experimental use.
T - Transitive bit T - Transitive bit
Value 0: The community is transitive across ASes Value 0: The community is transitive across ASes
Value 1: The community is non-transitive across ASes Value 1: The community is non-transitive across ASes
Remaining 6 bits: Indicates the structure of the community Remaining 6 bits: Indicates the structure of the community
Value Field: Value Field:
The encoding of the Value Field is dependent on the "type" of The encoding of the Value Field is dependent on the "type" of
the community as specified by the Type Field. the community as specified by the Type Field.
Two extended communities are declared equal only when all 8 octets of Two extended communities are declared equal only when all 8 octets of
their encoding are equal. the community are equal.
The two members in the tuple <Type, Value> should be enumerated to The two members in the tuple <Type, Value> should be enumerated to
specify any community value. Based on the value of the Type field, specify any community value. The remaining octets of the community
the remaining octets of the community should be interpreted. interpreted based on the value of the Type field.
3. Defined BGP Extended Community Types 3. Defined BGP Extended Community Types
This section introduces a few extended types and defines the format This section introduces a few extended types and defines the format
of the Value Field for those types. The types introduced here provide of the Value Field for those types. The types introduced here provide
"templates", where each template is identified by the high order "templates", where each template is identified by the high order
octet of the extended community Type field, and the lower order octet octet of the extended community Type field, and the lower order octet
(sub-type) is used to indicate a particular type of extended commu- (sub-type) is used to indicate a particular type of extended
nity. community.
3.1. Two-octet AS specific extended community 3.1. Two-octet AS specific extended community
This is an extended type with Type Field comprising of 2 octets and This is an extended type with Type Field comprising of 2 octets and
Value Field comprising of 6 octets. Value Field comprising of 6 octets.
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 or 0x40 | Sub-Type | Global Administrator | | 0x00 or 0x40 | Sub-Type | Global Administrator |
skipping to change at page 5, line 43 skipping to change at page 5, line 17
Global Administrator sub-field: 2 octets Global Administrator sub-field: 2 octets
This sub-field contains an Autonomous System number assigned by This sub-field contains an Autonomous System number assigned by
IANA. IANA.
Local Administrator sub-field: 4 octets Local Administrator sub-field: 4 octets
The organization identified by Autonomous System number in the The organization identified by Autonomous System number in the
Global Administrator sub-field, can encode any information in Global Administrator sub-field, can encode any information in
this sub-field. The format and meaning of the value encoded in this sub-field. The format and meaning of the value encoded in
this sub-field should be defined by the sub-type of the commu- this sub-field should be defined by the sub-type of the
nity. community.
3.2. IPv4 address specific extended community 3.2. IPv4 address specific extended community
This is an extended type with Type Field comprising of 2 octets and This is an extended type with Type Field comprising of 2 octets and
Value Field comprising of 6 octets. Value Field comprising of 6 octets.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0x01 or 0x41 | Sub-Type | Global Administrator | | 0x01 or 0x41 | Sub-Type | Global Administrator |
skipping to change at page 6, line 26 skipping to change at page 5, line 41
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The value of the high-order octet of this extended type is either The value of the high-order octet of this extended type is either
0x01 or 0x41. The low-order octet of this extended type is used to 0x01 or 0x41. The low-order octet of this extended type is used to
indicate sub-types. indicate sub-types.
The Value field consists of two sub-fields: The Value field consists of two sub-fields:
Global Administrator sub-field: 4 octets Global Administrator sub-field: 4 octets
This sub-field contains an IPv4 address assigned by IANA. This sub-field contains an IPv4 unicast address assigned by one
of the Internet registries.
Local Administrator sub-field: 2 octets Local Administrator sub-field: 2 octets
The organization which has been assigned the IPv4 address in The organization which has been assigned the IPv4 address in
the Global Administrator sub-field, can encode any information the Global Administrator sub-field, can encode any information
in this sub-field. The format and meaning of this value in this sub-field. The format and meaning of this value
encoded in this sub-field should be defined by the sub-type of encoded in this sub-field should be defined by the sub-type of
the community. the community.
3.3. Four-octet AS specific extended community 3.3. Opaque extended community
This is an extended type with Type Field comprising of 2 octets and
Value Field comprising of 6 octets.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0x02 or 0x42 | Sub-Type | Global Administrator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Global Administrator (cont.) | Local Administrator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The value of the high-order octet of this extended type is either
0x02 or 0x42. The low-order octet of this extended type is used to
indicate sub-types.
The Value Field consists of two sub-fields:
Global Administrator sub-field: 4 octets
This sub-field contains a 4-octets Autonomous System number
assigned by IANA.
Local Administrator sub-field: 2 octets
The organization identified by Autonomous System number in the
Global Administrator sub-field, can encode any information in
this sub-field. The format and meaning of the value encoded in
this sub-field should be defined by the sub-type of the commu-
nity.
3.4. Opaque extended community
This is an extended type with Type Field comprising of 2 octets and This is an extended type with Type Field comprising of 2 octets and
Value Field comprising of 6 octets. Value Field comprising of 6 octets.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0x03 or 0x43 | Sub-Type | Value | | 0x03 or 0x43 | Sub-Type | Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Value (cont.) | | Value (cont.) |
skipping to change at page 8, line 18 skipping to change at page 6, line 39
receive a set of routes (that carry this Community) carried by BGP. receive a set of routes (that carry this Community) carried by BGP.
This is transitive across the Autonomous system boundary. This is transitive across the Autonomous system boundary.
The Route Target Community is of an extended type. The Route Target Community is of an extended type.
The value of the high-order octet of the Type field for the Route The value of the high-order octet of the Type field for the Route
Target Community can be 0x00, 0x01 or 0x02. The value of the low- Target Community can be 0x00, 0x01 or 0x02. The value of the low-
order octet of the Type field for this community is 0x02. order octet of the Type field for this community is 0x02.
When the value of the high-order octet of the Type field is 0x00 or When the value of the high-order octet of the Type field is 0x00 or
0x02, the Local Administrator sub-field contains a number from a num- 0x02, the Local Administrator sub-field contains a number from a
bering space which is administered by the organization to which the numbering space which is administered by the organization to which
Autonomous System number carried in the Global Administrator subfield the Autonomous System number carried in the Global Administrator
has been assigned by an appropriate authority. subfield has been assigned by an appropriate authority.
When the value of the high-order octet of the Type field is 0x01, the When the value of the high-order octet of the Type field is 0x01, the
Local Administrator sub-field contains a number from a numbering Local Administrator sub-field contains a number from a numbering
space which is administered by the organization to which the IP space which is administered by the organization to which the IP
address carried in the Global Administrator subfield has been address carried in the Global Administrator subfield has been
assigned by an appropriate authority. assigned by an appropriate authority.
One possible use of the Route Target Community is specified in [BGP-
MPLS-VPN].
5. Route Origin Community 5. Route Origin Community
The Route Origin Community identifies one or more routers that inject The Route Origin Community identifies one or more routers that inject
a set of routes (that carry this Community) into BGP. This is transi- a set of routes (that carry this Community) into BGP. This is
tive across the Autonomous system boundary. transitive across the Autonomous system boundary.
The Route Origin Community is of an extended type. The Route Origin Community is of an extended type.
The value of the high-order octet of the Type field for the Route The value of the high-order octet of the Type field for the Route
Origin Community can be 0x00, 0x01 or 0x02. The value of the low- Origin Community can be 0x00, 0x01 or 0x02. The value of the low-
order octet of the Type field for this community is 0x03. order octet of the Type field for this community is 0x03.
When the value of the high-order octet of the Type field is 0x00 or When the value of the high-order octet of the Type field is 0x00 or
0x02, the Local Administrator sub-field contains a number from a num- 0x02, the Local Administrator sub-field contains a number from a
bering space which is administered by the organization to which the numbering space which is administered by the organization to which
Autonomous System number carried in the Global Administrator subfield the Autonomous System number carried in the Global Administrator
has been assigned by an appropriate authority. subfield has been assigned by an appropriate authority.
When the value of the high-order octet of the Type field is 0x01, the When the value of the high-order octet of the Type field is 0x01, the
Local Administrator sub-field contains a number from a numbering Local Administrator sub-field contains a number from a numbering
space which is administered by the organization to which the IP space which is administered by the organization to which the IP
address carried in the Global Administrator subfield has been address carried in the Global Administrator subfield has been
assigned by an appropriate authority. assigned by an appropriate authority.
6. Link Bandwidth Community One possible use of the Route Origin Community is specified in [BGP-
MPLS-VPN].
When a router receives a route from a directly connected external
neighbor (the external neighbor that is one IP hop away), and adver-
tises this route (via IBGP) to internal neighbors, as part of this
advertisement the router may carry the bandwidth of the link that
connects the router with the external neighbor. The bandwidth of such
a link is carried in the Link Bandwidth Community.
The Link Bandwidth Community is of an extended type.
The value of the high-order octet of the Type Field is 0x00. The
value of the low-order octet of the Type field for this community is
0x04.
The value of the Global Administrator sub-field in the Value Field
MUST represent the Autonomous System of the router that attaches the
Link Bandwidth Community.
The bandwidth of the link is expressed as 4 octets in IEEE floating
point format, units being bytes per second. It is carried in the
Local Administrator sub-field of the Value Field.
7. Operations 6. Operations
A BGP speaker may use the Extended Communities attribute to control A BGP speaker may use the Extended Communities attribute to control
which routing information it accepts or distributes to its peers. which routing information it accepts or distributes to its peers.
The Extended Community attribute MUST NOT be used to modify the BGP The Extended Community attribute MUST NOT be used to modify the BGP
best path selection algorithm in a way that leads to forwarding best path selection algorithm in a way that leads to forwarding
loops. loops.
A BGP speaker receiving a route that doesn't have the Extended Commu- A BGP speaker receiving a route that doesn't have the Extended
nities attribute MAY append this attribute to the route when propa- Communities attribute MAY append this attribute to the route when
gating it to its peers. propagating it to its peers.
A BGP speaker receiving a route with the Extended Communities A BGP speaker receiving a route with the Extended Communities
attribute MAY modify this attribute according to the local policy. attribute MAY modify this attribute according to the local policy.
By default if a range of routes is to be aggregated and the resultant By default if a range of routes is to be aggregated and the resultant
aggregates path attributes do not carry the ATOMIC_AGGREGATE aggregates path attributes do not carry the ATOMIC_AGGREGATE
attribute, then the resulting aggregate should have an Extended Com- attribute, then the resulting aggregate should have an Extended
munities path attribute which contains the set union of all the Communities path attribute which contains the set union of all the
Extended Communities from all of the aggregated routes. The default Extended Communities from all of the aggregated routes. The default
behavior could be overriden via local configuration, in which case behavior could be overriden via local configuration, in which case
handling the Extended Communities attribute in the presence of route handling the Extended Communities attribute in the presence of route
aggregation becomes a matter of the local policy of the BGP speaker aggregation becomes a matter of the local policy of the BGP speaker
that performs the aggregation. that performs the aggregation.
If a route has a non-transitivity extended community, then before If a route has a non-transitivity extended community, then before
advertising the route across the Autonomous system boundary the com- advertising the route across the Autonomous system boundary the
munity SHOULD be removed from the route. However, the community community SHOULD be removed from the route. However, the community
SHOULD NOT be removed when advertising the route across the BGP Con- SHOULD NOT be removed when advertising the route across the BGP
federation boundary. Confederation boundary.
A route may carry both the BGP Communities attribute as defined in A route may carry both the BGP Communities attribute as defined in
[RFC1997]), and the Extended BGP Communities attribute. In this case [RFC1997]), and the Extended BGP Communities attribute. In this case
the BGP Communities attribute is handled as specified in [RFC1997], the BGP Communities attribute is handled as specified in [RFC1997],
and the Extended BGP Communities attribute is handled as specified in and the Extended BGP Communities attribute is handled as specified in
this document. this document.
8. IANA Considerations 7. IANA Considerations
All the BGP Extended Communities contain a Type field for which IANA All the BGP Extended Communities contain a Type field for which IANA
is to create and maintain a registry entitled BGP Extended Communi- is to create and maintain a registry entitled "BGP Extended
ties Type. Communities Type".
The Type could be either regular or extended. For a regular Type the The Type could be either regular or extended. For a regular Type the
IANA allocates an 8-bits value; for an extended Type the IANA allo- IANA allocates an 8-bits value; for an extended Type the IANA
cates a 16-bits value. allocates a 16-bits value.
The value allocated for a regular Type MUST NOT be reused as the The value allocated for a regular Type MUST NOT be reused as the
value of the high-order octet when allocating an extended Type. The value of the high-order octet when allocating an extended Type. The
value of the high-order octet allocated for an extended Type MUST NOT value of the high-order octet allocated for an extended Type MUST NOT
be reused when allocating a regular Type. be reused when allocating a regular Type.
The Type field indicates where the Extended Community is transitive The Type field indicates where the Extended Community is transitive
or not. or not. Future requests for assignment of a Type value must specify
whether the Type value is intended for a transitive or a non-
transitive Extended Community.
Future assignment are to be made using either the Standards Action Future assignment are to be made using either the Standards Action
process defined in [RFC2434], or the Early IANA Allocation process process defined in [RFC2434], or the Early IANA Allocation process
defined in [kompella-zinin], or the "First Come First Served" policy defined in [kompella-zinin], or the "First Come First Served" policy
defined in [RFC2434]. defined in [RFC2434].
The following table summarizes the ranges for the assignment of The following table summarizes the ranges for the assignment of
Types: Types:
Type Standard Action First Come Type Standard Action First Come
skipping to change at page 11, line 4 skipping to change at page 9, line 17
The following table summarizes the ranges for the assignment of The following table summarizes the ranges for the assignment of
Types: Types:
Type Standard Action First Come Type Standard Action First Come
Early IANA Allocation First Served Early IANA Allocation First Served
------------------ --------------------- ------------ ------------------ --------------------- ------------
regular, transitive 0x90-0xbf 0x00-x3f regular, transitive 0x90-0xbf 0x00-x3f
regular, non-transitive 0xd0-0xff 0x40-0x7f regular, non-transitive 0xd0-0xff 0x40-0x7f
extended, transitive 0x9000-0xbfff 0x0000-0x3fff extended, transitive 0x9000-0xbfff 0x0000-0x3fff
extended, non-transitive 0xd000-0xffff 0x4000-0x7fff extended, non-transitive 0xd000-0xffff 0x4000-0x7fff
Assignments consist of a name and the value. Assignments consist of a name and the value.
The Type values 0x80-0x8f and 0xc0-0xcf for regular Types, and The Type values 0x80-0x8f and 0xc0-0xcf for regular Types, and
0x8000-0x8fff and 0xc000-0xcfff for extended Types are experimental, 0x8000-0x8fff and 0xc000-0xcfff for extended Types are for
and are not to be assigned by IANA. Experimental use as defined in RFC3692.
This document defines a class of extended communities called two- This document defines a class of extended communities called two-
octet AS specific extended community for which the IANA is to create octet AS specific extended community for which the IANA is to create
and maintain a registry entitled Two-octet AS Specific Extended Com- and maintain a registry entitled "Two-octet AS Specific Extended
munity. All the communities in this class are of extended Types. Community". All the communities in this class are of extended Types.
Future assignment are to be made using the "First Come First Served" Future assignment are to be made using the "First Come First Served"
policy defined in [RFC2434]. The Type values for the transitive com- policy defined in [RFC2434]. The Type values for the transitive
munities of the two-octet AS specific extended community class are communities of the two-octet AS specific extended community class are
0x0000-0x00ff, and for the non-transitive communities of that class 0x0000-0x00ff, and for the non-transitive communities of that class
are 0x4000-0x40ff. Assignments consist of a name and the value. are 0x4000-0x40ff. Assignments consist of a name and the value.
This document makes the following assignments for the two-octet AS This document makes the following assignments for the two-octet AS
specific extended community: specific extended community:
Name Type Value Name Type Value
---- ---------- ---- ----------
two-octet AS specific Route Target 0x0002 two-octet AS specific Route Target 0x0002
two-octet AS specific Route Origin 0x0003 two-octet AS specific Route Origin 0x0003
two-octet AS specific Link Bandwidth 0x0004
This document defines a class of extended communities called IPv4 This document defines a class of extended communities called IPv4
address specific extended community for which the IANA is to create address specific extended community for which the IANA is to create
and maintain a registry entitled IPv4 Address Specific Extended and maintain a registry entitled "IPv4 Address Specific Extended
Community. All the communities in this class are of extended Types. Community". All the communities in this class are of extended Types.
Future assignment are to be made using the "First Come First Served" Future assignment are to be made using the "First Come First Served"
policy defined in [RFC2434]. The Type values for the transitive policy defined in [RFC2434]. The Type values for the transitive
communities of the two-octet AS specific extended community class communities of the two-octet AS specific extended community class
are 0x0100-0x01ff, and for the non-transitive communities of that are 0x0100-0x01ff, and for the non-transitive communities of that
class are 0x4100-0x41ff. Assignments consist of a name and the class are 0x4100-0x41ff. Assignments consist of a name and the
value. value.
This document makes the following assignments for the IPv4 address This document makes the following assignments for the IPv4 address
specific extended community: specific extended community:
Name Type Value Name Type Value
---- ---------- ---- ----------
IPv4 address specific Route Target 0x0102 IPv4 address specific Route Target 0x0102
IPv4 address specific Route Origin 0x0103 IPv4 address specific Route Origin 0x0103
This document defines a class of extended communities called
four-octet AS specific extended community for which the IANA is to
create and maintain a registry entitled Four-octet AS Specific
Extended Community. All the communities in this class are of
extended Types. Future assignment are to be made using the "First
Come First Served" policy defined in [RFC2434]. The Type values for
the transitive communities of the two-octet AS specific extended
community class are 0x0200-0x02ff, and for the non-transitive
communities of that class are 0x4200-0x42ff. Assignments consist
of a name and the value.
This document makes the following assignments for the four-octet
AS specific extended community:
Name Type Value
---- ----------
four-octet AS specific Route Target 0x0202
four-octet AS specific Route Origin 0x0203
This document defines a class of extended communities called opaque This document defines a class of extended communities called opaque
extended community for which the IANA is to create and maintain a extended community for which the IANA is to create and maintain a
registry entitled Opaque Extended Community. All the communities registry entitled "Opaque Extended Community". All the communities
in this class are of extended Types. Future assignment are to be in this class are of extended Types. Future assignment are to be
made using the "First Come First Served" policy defined in [RFC2434]. made using the "First Come First Served" policy defined in [RFC2434].
The Type values for the transitive communities of the opaque extended The Type values for the transitive communities of the opaque extended
community class are 0x0300-0x03ff, and for the non-transitive community class are 0x0300-0x03ff, and for the non-transitive
communities of that class are 0x4300-0x43ff. Assignments consist communities of that class are 0x4300-0x43ff. Assignments consist
of a name and the value. of a name and the value.
When requesting an allocation from more than one registry defined When requesting an allocation from more than one registry defined
above, one may ask for allocating the same Type value from above, one may ask for allocating the same Type value from
these registries. If possible, the IANA should accommodate such these registries. If possible, the IANA should accommodate such
requests. requests.
9. Security Considerations 8. Security Considerations
This extension to BGP has similar security implications as BGP
Communities [RFC1997].
This extension to BGP does not change the underlying security issues. This extension to BGP does not change the underlying security issues.
Specifically, an operator who is relying on the information carried
in BGP must have a transitive trust relationship back to the source
of the information. Specifying the mechanism(s) to provide such a
relationship is beyond the scope of this document.
10. Intellectual Property Considerations 9. Intellectual Property Considerations
This section is taken from Section 10.4 of [RFC2026]. This section is taken from Section 5 of RFC 3668.
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to per- Intellectual Property Rights or other rights that might be claimed to
tain to the implementation or use of the technology described in this pertain to the implementation or use of the technology described in
document or the extent to which any license under such rights might this document or the extent to which any license under such rights
or might not be available; neither does it represent that it has made might or might not be available; nor does it represent that it has
any effort to identify any such rights. Information on the IETF's made any independent effort to identify any such rights. Information
procedures with respect to rights in standards-track and standards- on the procedures with respect to rights in RFC documents can be
related documentation can be found in BCP-11. Copies of claims of found in BCP 78 and BCP 79.
rights made available for publication and any assurances of licenses
to be made available, or the result of an attempt made to obtain a Copies of IPR disclosures made to the IETF Secretariat and any
general license or permission for the use of such proprietary rights assurances of licenses to be made available, or the result of an
by implementors or users of this specification can be obtained from attempt made to obtain a general license or permission for the use of
the IETF Secretariat. 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 The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF Executive this standard. Please address the information to the IETF at ietf-
Director. ipr@ietf.org.
11. Copyright Notice
Copyright (C) The Internet Society (date). All Rights Reserved. 10. Copyright Notice
This document and translations of it may be copied and furnished to Copyright (C) The Internet Society (2005).
others, and derivative works that comment on or otherwise explain it
or assist in its implmentation may be prepared, copied, published and
distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this doc-
ument itself may not be modified in any way, such as by removing the
copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of develop-
ing Internet standards in which case the procedures for copyrights
defined in the Internet Standards process must be followed, or as
required to translate it into languages other than English.
The limited permissions granted above are perpetual and will not be This document is subject to the rights, licenses and restrictions
revoked by the Internet Society or its successors or assigns. contained in BCP 78, and except as set forth therein, the authors
retain all their rights.
This document and the information contained herein is provided on an This document and the information contained herein are provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MER- INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
CHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
12. Acknowledgements 11. Acknowledgements
The authors would like to thank John Hawkinson, Jeffrey Haas, Bruno The authors would like to thank John Hawkinson, Jeffrey Haas, Bruno
Rijsman, and Alex Zinin for their suggestions and feedback. Rijsman, Bill Fenner, and Alex Zinin for their suggestions and
feedback.
13. Normative References 12. Normative References
[BGP-4] Rekhter, Y., and T. Li, "A Border Gateway Protocol 4 [BGP-4] Rekhter, Y., and T. Li, "A Border Gateway Protocol 4
(BGP-4)", RFC 1771, March 1995. (BGP-4)", RFC 1771, March 1995.
[RFC1997] Chandra, R., Traina, P., Li, T., "BGP Communities [RFC1997] Chandra, R., Traina, P., Li, T., "BGP Communities
Attribute", RFC1997, August 1996. Attribute", RFC1997, August 1996.
[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.
13. Non-normative References
[BGP-MPLS-VPN] Rosen, E., Rekhter, Y., "BGP/MPLS IP VPNs", draft-
ietf-l3vpn-rfc2547bis-03.txt
[RFC1997] Chandra, R., Traina, P., Li, T., "BGP Communities
Attribute" RFC1997
14. Author Information 14. Author Information
Srihari R. Sangli Srihari R. Sangli
Cisco Systems, Inc. Cisco Systems, Inc.
e-mail: rsrihari@cisco.com
Dan Tappan Dan Tappan
Cisco Systems, Inc. Cisco Systems, Inc.
250 Apollo Drive 250 Apollo Drive
Chelmsford, MA 01824 Chelmsford, MA 01824
e-mail: tappan@cisco.com e-mail: tappan@cisco.com
Yakov Rekhter Yakov Rekhter
Juniper Networks, Inc. Juniper Networks, Inc.
1194 N. Mathilda Ave 1194 N. Mathilda Ave
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