BGP Extensions for Routing Policy Distribution (RPD)
draft-ietf-idr-rpd-04
Network Working Group Z. Li
Internet-Draft Huawei
Intended status: Standards Track L. Ou
Expires: December 11, 2020 Y. Luo
China Telcom Co., Ltd.
S. Lu
Tencent
H. Chen
Futurewei
S. Zhuang
H. Wang
Huawei
June 9, 2020
BGP Extensions for Routing Policy Distribution (RPD)
draft-ietf-idr-rpd-04
Abstract
It is hard to adjust traffic and optimize traffic paths on a
traditional IP network from time to time through manual
configurations. It is desirable to have an automatic mechanism for
setting up routing policies, which adjust traffic and optimize
traffic paths automatically. This document describes BGP Extensions
for Routing Policy Distribution (BGP RPD) to support this.
Requirements Language
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].
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
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This Internet-Draft will expire on December 11, 2020.
Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Problem Statements . . . . . . . . . . . . . . . . . . . . . 3
3.1. Inbound Traffic Control . . . . . . . . . . . . . . . . . 3
3.2. Outbound Traffic Control . . . . . . . . . . . . . . . . 4
4. Protocol Extensions . . . . . . . . . . . . . . . . . . . . . 5
4.1. Using a New AFI and SAFI . . . . . . . . . . . . . . . . 5
4.2. BGP Wide Community . . . . . . . . . . . . . . . . . . . 6
4.2.1. New Wide Community Atoms . . . . . . . . . . . . . . 6
4.3. Capability Negotiation . . . . . . . . . . . . . . . . . 12
5. Consideration . . . . . . . . . . . . . . . . . . . . . . . . 12
5.1. Route-Policy . . . . . . . . . . . . . . . . . . . . . . 12
6. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 13
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
10.1. Normative References . . . . . . . . . . . . . . . . . . 16
10.2. Informative References . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
It is difficult to optimize traffic paths on a traditional IP network
because of:
o Heavy configuration and error prone. Traffic can only be adjusted
device by device. All routers that the traffic traverses need to
be configured. The configuration workload is heavy. The
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operation is not only time consuming but also prone to
misconfiguration for Service Providers.
o Complex. The routing policies used to control network routes are
complex, posing difficulties to subsequent maintenance, high
maintenance skills are required.
It is desirable to have an automatic mechanism for setting up routing
policies, which can simplify the routing policies configuration.
This document describes extensions to BGP for Routing Policy
Distribution to resolve these issues.
2. Terminology
The following terminology is used in this document.
o ACL:Access Control List
o BGP: Border Gateway Protocol
o FS: Flow Specification
o PBR:Policy-Based Routing
o RPD: Routing Policy Distribution
o VPN: Virtual Private Network
3. Problem Statements
It is obvious that providers have the requirements to adjust their
business traffic from time to time because:
o Business development or network failure introduces link congestion
and overload.
o Network transmission quality is decreased as the result of delay,
loss and they need to adjust traffic to other paths.
o To control OPEX and CPEX, prefer the transit provider with lower
price.
3.1. Inbound Traffic Control
In the scenario below, for the reasons above, the provider of AS100
saying P may wish the inbound traffic from AS200 enters AS100 through
link L3 instead of the others. Since P doesn't have any
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administration over AS200, so there is no way for P to modify the
route selection criteria directly.
Traffic from PE1 to Prefix1
----------------------------------->
+-----------------+ +-------------------------+
| +---------+ | L1 | +----+ +----------+|
| |Speaker1 | +------------+ |IGW1| |policy ||
| +---------+ |** L2**| +----+ |controller||
| | ** ** | +----------+|
| +---+ | **** | |
| |PE1| | **** | |
| +---+ | ** ** | |
| +---------+ |** L3**| +----+ |
| |Speaker2 | +------------+ |IGW2| AS100 |
| +---------+ | L4 | +----+ |
| | | |
| AS200 | | |
| | | ... |
| | | |
| +---------+ | | +----+ +-------+ |
| |Speakern | | | |IGWn| |Prefix1| |
| +---------+ | | +----+ +-------+ |
+-----------------+ +-------------------------+
Prefix1 advertised from AS100 to AS200
<----------------------------------------
Inbound Traffic Control case
3.2. Outbound Traffic Control
In the scenario below, the provider of AS100 saying P prefers link L3
for the traffic to the destination Prefix2 among multiple exits and
links. This preference can be dynamic and changed frequently because
of the reasons above. So the provider P expects an efficient and
convenient solution.
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Traffic from PE2 to Prefix2
----------------------------------->
+-------------------------+ +-----------------+
|+----------+ +----+ |L1 | +---------+ |
||policy | |IGW1| +------------+ |Speaker1 | |
||controller| +----+ |** **| +---------+ |
|+----------+ |L2** ** | +-------+|
| | **** | |Prefix2||
| | **** | +-------+|
| |L3** ** | |
| AS100 +----+ |** **| +---------+ |
| |IGW2| +------------+ |Speaker2 | |
| +----+ |L4 | +---------+ |
| | | |
|+---+ | | AS200 |
||PE2| ... | | |
|+---+ | | |
| +----+ | | +---------+ |
| |IGWn| | | |Speakern | |
| +----+ | | +---------+ |
+-------------------------+ +-----------------+
Prefix2 advertised from AS200 to AS100
<----------------------------------------
Outbound Traffic Control case
4. Protocol Extensions
A solution is proposed to use a new AFI and SAFI with the BGP Wide
Community for encoding a routing policy.
4.1. Using a New AFI and SAFI
A new AFI and SAFI are defined: the Routing Policy AFI whose
codepoint 16398 has been assigned by IANA, and SAFI whose codepoint
75 has been assigned by IANA.
The AFI and SAFI pair uses a new NLRI, which is defined as follows:
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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
+-+-+-+-+-+-+-+-+
| NLRI Length |
+-+-+-+-+-+-+-+-+
| Policy Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Distinguisher (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer IP (4/16 octets) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where:
NLRI Length: 1 octet represents the length of NLRI.
Policy Type: 1 octet indicates the type of a policy. 1 is for
export policy. 2 is for import policy.
Distinguisher: 4 octet value uniquely identifies the policy in the
peer.
Peer IP: 4/16 octet value indicates an IPv4/IPv6 peer.
The NLRI containing the Routing Policy is carried in a BGP UPDATE
message, which MUST contain the BGP mandatory attributes and MAY also
contain some BGP optional attributes.
When receiving a BGP UPDATE message, a BGP speaker processes it only
if the peer IP address in the NLRI is the IP address of the BGP
speaker or 0.
The content of the Routing Policy is encoded in a BGP Wide Community.
4.2. BGP Wide Community
The BGP wide community is defined in
[I-D.ietf-idr-wide-bgp-communities]. It can be used to facilitate
the delivery of new network services, and be extended easily for
distributing different kinds of routing policies.
4.2.1. New Wide Community Atoms
A wide community Atom is a TLV (or sub-TLV), which may be included in
a BGP wide community container (or BGP wide community for short)
containing some BGP Wide Community TLVs. Three BGP Wide Community
TLVs are defined in [I-D.ietf-idr-wide-bgp-communities], which are
BGP Wide Community Target(s) TLV, Exclude Target(s) TLV, and
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Parameter(s) TLV. Each of these TLVs comprises a series of Atoms,
each of which is a TLV (or sub-TLV). A new wide community Atom is
defined for BGP Wide Community Target(s) TLV and a few new Atoms are
defined for BGP Wide Community Parameter(s) TLV. For your reference,
the format of the TLV is illustrated below:
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
+-+-+-+-+-+-+-+-++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Value (variable) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Format of Wide Community Atom TLV
A RouteAttr Atom TLV (or RouteAttr TLV/sub-TLV for short) is defined
and may be included in a Target TLV. It has the following format.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD1) | Length (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| sub-TLVs ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Format of RouteAttr Atom TLV
The Type for RouteAttr is TBD1 (suggested value 48) to be assigned by
IANA. In RouteAttr TLV, three sub-TLVs are defined: IP Prefix, AS-
Path and Community sub-TLV.
An IP prefix sub-TLV gives matching criteria on IPv4 prefixes. Its
format is illustrated below:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD2) | Length (N x 8) |M-Type | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Mask | GeMask | LeMask |M-Type | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ . . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Mask | GeMask | LeMask |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Format of IPv4 Prefix sub-TLV
Type: TBD2 (suggested value 1) for IPv4 Prefix is to be assigned by
IANA.
Length: N x 8, where N is the number of tuples <M-Type, Flags, IPv4
Address, Mask, GeMask, LeMask>.
M-Type: 4 bits for match types, four of which are defined:
M-Type = 0: Exact match.
M-Type = 1: Match prefix greater and equal to the given masks.
M-Type = 2: Match prefix less and equal to the given masks.
M-Type = 3: Match prefix within the range of the given masks.
Flags: 4 bits. No flags are currently defined.
IPv4 Address: 4 octets for an IPv4 address.
Mask: 1 octet for the mask length.
GeMask: 1 octet for match range, must be less than Mask or be 0.
LeMask: 1 octet for match range, must be greater than Mask or be 0.
For example, tuple <M-Type=0, Flags=0, IPv4 Address = 1.1.0.0, Mask =
22, GeMask = 0, LeMask = 0> represents an exact IP prefix match for
1.1.0.0/22.
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<M-Type=1, Flags=0, IPv4 Address = 16.1.0.0, Mask = 24, GeMask = 24,
LeMask = 0> represents match IP prefix 1.1.0.0/24 greater-equal 24.
<M-Type=2, Flags=0, IPv4 Address = 17.1.0.0, Mask = 24, GeMask = 0,
LeMask = 26> represents match IP prefix 17.1.0.0/24 less-equal 26.
<M-Type=3, Flags=0, IPv4 Address = 18.1.0.0, Mask = 24, GeMask = 24,
LeMask = 32> represents match IP prefix 18.1.0.0/24 greater-equal to
24 and less-equal 32.
Similarly, an IPv6 Prefix sub-TLV represents match criteria on IPv6
prefixes. Its format is illustrated below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type(TBD3) | Length (N x 20) |M-Type | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Address (16 octets) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Mask | GeMask | LeMask |M-Type | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ . . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Address (16 octets ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Mask | GeMask | LeMask |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Format of IPv6 Prefix sub-TLV
An AS-Path sub-TLV represents a match criteria in a regular
expression string. Its format is illustrated below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD4) | Length (Variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AS-Path Regex String |
: :
| ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Format of AS Path sub-TLV
Type: TBD4 (suggested value 2) for AS-Path is to be assigned by
IANA.
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Length: Variable, maximum is 1024.
AS-Path Regex String: AS-Path regular expression string.
A community sub-TLV represents a list of communities to be matched
all. Its format is illustrated below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD5) | Length (N x 4 + 1) | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Community 1 Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ . . . ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Community N Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Format of Community sub-TLV
Type: TBD5 (suggested value 3) for Community is to be assigned by
IANA.
Length: N x 4 + 1, where N is the number of communities.
Flags: 1 octet. No flags are currently defined.
In Parameter(s) TLV, two action sub-TLVs are defined: MED change sub-
TLV and AS-Path change sub-TLV. When the community in the container
is MATCH AND SET ATTR, the Parameter(s) TLV includes some of these
sub-TLVs. When the community is MATCH AND NOT ADVERTISE, the
Parameter(s) TLV's value is empty.
A MED change sub-TLV indicates an action to change the MED. Its
format is illustrated below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD6) | Length (5) | OP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Format of MED Change sub-TLV
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Type: TBD6 (suggested value 1) for MED Change is to be assigned by
IANA.
Length: 5.
OP: 1 octet. Three are defined:
OP = 0: assign the Value to the existing MED.
OP = 1: add the Value to the existing MED. If the sum is greater
than the maximum value for MED, assign the maximum value to
MED.
OP = 2: subtract the Value from the existing MED. If the
existing MED minus the Value is less than 0, assign 0 to MED.
Value: 4 octets.
An AS-Path change sub-TLV indicates an action to change the AS-Path.
Its format is illustrated below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (TBD7) | Length (n x 5) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AS1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Count1 |
+-+-+-+-+-+-+-+-+
~ . . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ASn |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Countn |
+-+-+-+-+-+-+-+-+
Format of AS-Path Change sub-TLV
Type: TBD7 (suggested value 2) for AS-Path Change is to be assigned
by IANA.
Length: n x 5.
ASi: 4 octet. An AS number.
Counti: 1 octet. ASi repeats Counti times.
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The sequence of AS numbers are added to the existing AS Path.
4.3. Capability Negotiation
It is necessary to negotiate the capability to support BGP Extensions
for Routing Policy Distribution (RPD). The BGP RPD Capability is a
new BGP capability [RFC5492]. The Capability Code for this
capability is to be specified by the IANA. The Capability Length
field of this capability is variable. The Capability Value field
consists of one or more of the following tuples:
+--------------------------------------------------+
| Address Family Identifier (2 octets) |
+--------------------------------------------------+
| Subsequent Address Family Identifier (1 octet) |
+--------------------------------------------------+
| Send/Receive (1 octet) |
+--------------------------------------------------+
BGP RPD Capability
The meaning and use of the fields are as follows:
Address Family Identifier (AFI): This field is the same as the one
used in [RFC4760].
Subsequent Address Family Identifier (SAFI): This field is the same
as the one used in [RFC4760].
Send/Receive: This field indicates whether the sender is (a) willing
to receive Routing Policies from its peer (value 1), (b) would like
to send Routing Policies to its peer (value 2), or (c) both (value 3)
for the <AFI, SAFI>.
5. Consideration
5.1. Route-Policy
Routing policies are used to filter routes and control how routes are
received and advertised. If route attributes, such as reachability,
are changed, the path along which network traffic passes changes
accordingly.
When advertising, receiving, and importing routes, the router
implements certain policies based on actual networking requirements
to filter routes and change the attributes of the routes. Routing
policies serve the following purposes:
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o Control route advertising: Only routes that match the rules
specified in a policy are advertised.
o Control route receiving: Only the required and valid routes are
received. This reduces the size of the routing table and improves
network security.
o Filter and control imported routes: A routing protocol may import
routes discovered by other routing protocols. Only routes that
satisfy certain conditions are imported to meet the requirements
of the protocol.
o Modify attributes of specified routes Attributes of the routes:
that are filtered by a routing policy are modified to meet the
requirements of the local device.
o Configure fast reroute (FRR): If a backup next hop and a backup
outbound interface are configured for the routes that match a
routing policy, IP FRR, VPN FRR, and IP+VPN FRR can be
implemented.
Routing policies are implemented using the following procedures:
1. Define rules: Define features of routes to which routing policies
are applied. Users define a set of matching rules based on
different attributes of routes, such as the destination address
and the address of the router that advertises the routes.
2. Implement the rules: Apply the matching rules to routing policies
for advertising, receiving, and importing routes.
6. Contributors
The following people have substantially contributed to the definition
of the BGP-FS RPD and to the editing of this document:
Peng Zhou
Huawei
Email: Jewpon.zhou@huawei.com
7. Security Considerations
Protocol extensions defined in this document do not affect the BGP
security other than those as discussed in the Security Considerations
section of [RFC5575].
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8. Acknowledgements
The authors would like to thank Acee Lindem, Jeff Haas, Jie Dong,
Lucy Yong, Qiandeng Liang, Zhenqiang Li for their comments to this
work.
9. IANA Considerations
IANA has assigned a new AFI of value 16398 from the registry "Address
Family Numbers" for Routing Policy.
IANA has assigned a new SAFI of value 75 from the registry
"Subsequent Address Family Identifiers (SAFI) Parameters" for Routing
Policy.
This document defines a new registry called "Routing Policy Type".
The allocation policy of this registry is "First Come First Served
(FCFS)" according to [RFC8126].
Following code points are defined:
+-------------+-----------------------------------+-------------+
| Code Point | Description | Reference |
+-------------+-----------------------------------+-------------+
| 0 | Reserved | |
+-------------+-----------------------------------+-------------+
| 1 | Export Policy |This document|
+-------------+-----------------------------------+-------------+
| 2 | Import Policy |This document|
+-------------+-----------------------------------+-------------+
| 3 - 255 | To be assigned in FCFS | |
+-------------+-----------------------------------+-------------+
This document requests assigning a code-point from the registry "BGP
Community Container Atom Types" as follows:
+---------------------+------------------------------+-------------+
| TLV Code Point | Description | Reference |
+---------------------+------------------------------+-------------+
| TBD1 (48 suggested) | RouteAttr Atom |This document|
+---------------------+------------------------------+-------------+
This document defines a new registry called "Route Attributes Sub-
TLV" under RouteAttr Atom TLV. The allocation policy of this
registry is "First Come First Served (FCFS)" according to [RFC8126].
Following Sub-TLV code points are defined:
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+-------------+-----------------------------------+-------------+
| Code Point | Description | Reference |
+-------------+-----------------------------------+-------------+
| 0 | Reserved | |
+-------------+-----------------------------------+-------------+
| 1 | IPv4 Prefix Sub-TLV |This document|
+-------------+-----------------------------------+-------------+
| 2 | AS-Path Sub-TLV |This document|
+-------------+-----------------------------------+-------------+
| 3 | Community Sub-TLV |This document|
+-------------+-----------------------------------+-------------+
| 4 | IPv6 Prefix Sub-TLV |This document|
+-------------+-----------------------------------+-------------+
| 5 - 255 | To be assigned in FCFS | |
+-------------+-----------------------------------+-------------+
This document defines a new registry called "Attribute Change Sub-
TLV" under Parameter(s) TLV. The allocation policy of this registry
is "First Come First Served (FCFS)" according to [RFC8126].
Following Sub-TLV code points are defined:
+-------------+-----------------------------------+-------------+
| Code Point | Description | Reference |
+-------------+-----------------------------------+-------------+
| 0 | Reserved | |
+-------------+-----------------------------------+-------------+
| 1 | MED Change Sub-TLV |This document|
+-------------+-----------------------------------+-------------+
| 2 | AS-Path Change Sub-TLV |This document|
+-------------+-----------------------------------+-------------+
| 3 - 255 | To be assigned in FCFS | |
+-------------+-----------------------------------+-------------+
This document requests assigning a new Code Point from the registry
"Capability Codes" for Routing Policy Distribution as follows:
+----------------+--------------------------------+-------------+
| Code Point | Description | Reference |
+----------------+--------------------------------+-------------+
| 66 (Suggested)| Routing Policy Distribution |This document|
+----------------+--------------------------------+-------------+
10. References
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10.1. Normative References
[I-D.ietf-idr-wide-bgp-communities]
Raszuk, R., Haas, J., Lange, A., Decraene, B., Amante, S.,
and P. Jakma, "BGP Community Container Attribute", draft-
ietf-idr-wide-bgp-communities-05 (work in progress), July
2018.
[RFC1997] Chandra, R., Traina, P., and T. Li, "BGP Communities
Attribute", RFC 1997, DOI 10.17487/RFC1997, August 1996,
<https://www.rfc-editor.org/info/rfc1997>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271,
DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>.
[RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760,
DOI 10.17487/RFC4760, January 2007,
<https://www.rfc-editor.org/info/rfc4760>.
[RFC5492] Scudder, J. and R. Chandra, "Capabilities Advertisement
with BGP-4", RFC 5492, DOI 10.17487/RFC5492, February
2009, <https://www.rfc-editor.org/info/rfc5492>.
[RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
and D. McPherson, "Dissemination of Flow Specification
Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009,
<https://www.rfc-editor.org/info/rfc5575>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
10.2. Informative References
[I-D.ietf-idr-registered-wide-bgp-communities]
Raszuk, R. and J. Haas, "Registered Wide BGP Community
Values", draft-ietf-idr-registered-wide-bgp-communities-02
(work in progress), May 2016.
Li, et al. Expires December 11, 2020 [Page 16]
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Authors' Addresses
Zhenbin Li
Huawei
Huawei Bld., No.156 Beiqing Rd.
Beijing 100095
China
Email: lizhenbin@huawei.com
Liang Ou
China Telcom Co., Ltd.
109 West Zhongshan Ave,Tianhe District
Guangzhou 510630
China
Email: ouliang@chinatelecom.cn
Yujia Luo
China Telcom Co., Ltd.
109 West Zhongshan Ave,Tianhe District
Guangzhou 510630
China
Email: luoyuj@sdu.edu.cn
Sujian Lu
Tencent
Tengyun Building,Tower A ,No. 397 Tianlin Road
Shanghai, Xuhui District 200233
China
Email: jasonlu@tencent.com
Huaimo Chen
Futurewei
Boston, MA
USA
Email: Huaimo.chen@futurewei.com
Li, et al. Expires December 11, 2020 [Page 17]
Internet-Draft BGP RPD June 2020
Shunwan Zhuang
Huawei
Huawei Bld., No.156 Beiqing Rd.
Beijing 100095
China
Email: zhuangshunwan@huawei.com
Haibo Wang
Huawei
Huawei Bld., No.156 Beiqing Rd.
Beijing 100095
China
Email: rainsword.wang@huawei.com
Li, et al. Expires December 11, 2020 [Page 18]