draft-ietf-bess-orf-covering-prefixes-06.txt   rfc7543.txt 
BESS Working Group H. Jeng Internet Engineering Task Force (IETF) H. Jeng
Internet-Draft AT&T Request for Comments: 7543 AT&T
Intended status: Standards Track L. Jalil Category: Standards Track L. Jalil
Expires: September 7, 2015 Verizon ISSN: 2070-1721 Verizon
R. Bonica R. Bonica
Juniper Networks Juniper Networks
K. Patel K. Patel
Cisco Systems Cisco Systems
L. Yong L. Yong
Huawei Technologies Huawei Technologies
March 6, 2015 May 2015
Covering Prefixes Outbound Route Filter for BGP-4 Covering Prefixes Outbound Route Filter for BGP-4
draft-ietf-bess-orf-covering-prefixes-06
Abstract Abstract
This document defines a new Outbound Route Filter (ORF) type, called This document defines a new Outbound Route Filter (ORF) type, called
the "Covering Prefixes ORF (CP-ORF)". CP-ORF is applicable in the Covering Prefixes ORF (CP-ORF). CP-ORF is applicable in Virtual
Virtual Hub-and-Spoke VPNs. It also is applicable in BGP/MPLS Hub-and-Spoke VPNs. It also is applicable in BGP/MPLS Ethernet VPN
Ethernet VPN (EVPN) networks. (EVPN) networks.
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 Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
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 http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
This Internet-Draft will expire on September 7, 2015. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7543.
Copyright Notice Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. CP-ORF Encoding . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Requirements Language . . . . . . . . . . . . . . . . . . 4
3. Processing Rules . . . . . . . . . . . . . . . . . . . . . . 6 2. CP-ORF Encoding . . . . . . . . . . . . . . . . . . . . . . . 4
4. Applicability In Virtual Hub-and-Spoke VPNs . . . . . . . . . 9 3. Processing Rules . . . . . . . . . . . . . . . . . . . . . . 7
4.1. Multicast Considerations . . . . . . . . . . . . . . . . 12 4. Applicability in Virtual Hub-and-Spoke VPNs . . . . . . . . . 10
5. Applicability In BGP/MPLS Ethernet VPN (EVPN) . . . . . . . . 12 4.1. Multicast Considerations . . . . . . . . . . . . . . . . 13
6. Clean-up . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5. Applicability in BGP/MPLS Ethernet VPN (EVPN) . . . . . . . . 13
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 6. Clean-up . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8. Security Considerations . . . . . . . . . . . . . . . . . . . 17 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 17 8. Security Considerations . . . . . . . . . . . . . . . . . . . 18
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 17 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 17 9.1. Normative References . . . . . . . . . . . . . . . . . . 18
11.1. Normative References . . . . . . . . . . . . . . . . . . 17 9.2. Informative References . . . . . . . . . . . . . . . . . 19
11.2. Informative References . . . . . . . . . . . . . . . . . 18 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 20
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19 Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21
1. Introduction 1. Introduction
A BGP [RFC4271] speaker can send Outbound Route Filters (ORF) A BGP [RFC4271] speaker can send Outbound Route Filters (ORFs)
[RFC5291] to a peer. The peer uses ORFs to filter routing updates [RFC5291] to a peer. The peer uses ORFs to filter routing updates
that it sends to the BGP speaker. Using ORF, a BGP speaker can that it sends to the BGP speaker. Using ORF, a BGP speaker can
realize a "route pull" paradigm, in which the BGP speaker, on demand, realize a "route pull" paradigm in which the BGP speaker, on demand,
pulls certain routes from the peer. pulls certain routes from the peer.
This document defines a new ORF-type, called the "Covering Prefixes This document defines a new ORF-type, called the Covering Prefixes
ORF (CP-ORF)". A BGP speaker sends a CP-ORF to a peer in order to ORF (CP-ORF). A BGP speaker sends a CP-ORF to a peer in order to
pull routes that cover a specified host address. A prefix covers a pull routes that cover a specified host address. A prefix covers a
host address if it can be used to forward traffic towards that host host address if it can be used to forward traffic towards that host
address. Section 3 provides a more complete description of covering address. Section 3 provides a more complete description of covering
prefix selection criteria. prefix selection criteria.
CP-ORF is applicable in Virtual Hub-and-Spoke VPNs [RFC7024] CP-ORF is applicable in Virtual Hub-and-Spoke VPNs [RFC7024]
[RFC4364]. It also is applicable BGP/MPLS Ethernet VPN (EVPN) [RFC4364]. It also is applicable BGP/MPLS Ethernet VPN (EVPN)
[RFC7432] networks. [RFC7432] networks.
1.1. Terminology 1.1. Terminology
This document uses the following terms: This document uses the following terms:
o Address Family Identifier (AFI) - defined in [RFC4760] o Address Family Identifier (AFI) - defined in [RFC4760]
o Subsequent Address Family Identifier (SAFI) - defined in [RFC4760] o Subsequent Address Family Identifier (SAFI) - defined in [RFC4760]
o VPN IP Default Route - defined in [RFC7024]. o Route Target (RT) - defined in [RFC4364]
o V-Hub - defined in [RFC7024]. o VPN-IP Default Route - defined in [RFC7024]
o V-Spoke - defined in [RFC7024]. o Virtual Hub (V-hub) - defined in [RFC7024]
o Virtual Spoke (V-spoke) - defined in [RFC7024]
o BGP/MPLS Ethernet VPN (EVPN) - defined in [RFC7432] o BGP/MPLS Ethernet VPN (EVPN) - defined in [RFC7432]
o EVPN Instance (EVI) - defined in [RFC7432] o EVPN Instance (EVI) - defined in [RFC7432]
o MAC - Media Access Control
o Unknown MAC Route (UMR) - A regular EVPN MAC/IP Advertisement o Unknown MAC Route (UMR) - A regular EVPN MAC/IP Advertisement
route where the MAC Address Length is set to 48 and the MAC route where the MAC Address Length is set to 48 and the MAC
address to 00:00:00:00:00:00 address to 00:00:00:00:00:00
o Default MAC Gateway (DMG) - An EVPN PE that advertises a UMR o Default MAC Gateway (DMG) - An EVPN Provider Edge (PE) that
advertises a UMR
1.2. 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].
2. CP-ORF Encoding 2. CP-ORF Encoding
RFC 5291 augments the BGP ROUTE-REFRESH message so that it can carry RFC 5291 augments the BGP ROUTE-REFRESH message so that it can carry
ORF entries. When the ROUTE-REFRESH message carries ORF entries, it ORF entries. When the ROUTE-REFRESH message carries ORF entries, it
includes the following fields: includes the following fields:
o AFI [IANA.AFI] o AFI [IANA.AFI]
o SAFI [IANA.SAFI] o SAFI [IANA.SAFI]
skipping to change at page 4, line 4 skipping to change at page 4, line 31
o When-to-refresh (IMMEDIATE or DEFERRED) o When-to-refresh (IMMEDIATE or DEFERRED)
o ORF Type o ORF Type
o Length (of ORF entries) o Length (of ORF entries)
The ROUTE-REFRESH message also contains a list of ORF entries. Each The ROUTE-REFRESH message also contains a list of ORF entries. Each
ORF entry contains the following fields: ORF entry contains the following fields:
o Action (ADD, REMOVE, or REMOVE-ALL) o Action (ADD, REMOVE, or REMOVE-ALL)
o Match (PERMIT or DENY) o Match (PERMIT or DENY)
The ORF entry may also contain Type-specific information. Type- The ORF entry may also contain Type-specific information. Type-
specific information is present only when the Action is equal to ADD specific information is present only when the Action is equal to ADD
or REMOVE. It is not present when the Action is equal to REMOVE-ALL. or REMOVE. It is not present when the Action is equal to REMOVE-ALL.
When the BGP ROUTE-REFRESH message carries CP-ORF entries, the When the BGP ROUTE-REFRESH message carries CP-ORF entries, the
following conditions MUST be true: following conditions MUST be true:
o ORF Type MUST be equal to CP-ORF (65). o The ORF Type MUST be equal to CP-ORF (65).
o The AFI MUST be equal to IPv4, IPv6 or L2VPN o The AFI MUST be equal to IPv4, IPv6, or Layer 2 VPN (L2VPN).
o If the AFI is equal to IPv4 or IPv6, SAFI MUST be equal to MPLS- o If the AFI is equal to IPv4 or IPv6, the SAFI MUST be equal to
labeled VPN address MPLS-labeled VPN address.
o If the AFI is equal to L2VPN, the SAFI MUST be equal to BGP EVPN o If the AFI is equal to L2VPN, the SAFI MUST be equal to BGP EVPN.
o Match field MUST be equal to PERMIT o The Match field MUST be equal to PERMIT.
Figure 1 depicts the encoding of the CP-ORF type-specific Figure 1 depicts the encoding of the CP-ORF Type-specific
information. information.
+--------------------------------+ +--------------------------------+
| Sequence (32 bits) | | Sequence (32 bits) |
+--------------------------------+ +--------------------------------+
| Minlen (8 bits) | | Minlen (8 bits) |
+--------------------------------+ +--------------------------------+
| Maxlen (8 bits) | | Maxlen (8 bits) |
+--------------------------------+ +--------------------------------+
| VPN Route Target (64 bits) | | VPN Route Target (64 bits) |
+--------------------------------+ +--------------------------------+
| Import Route Target (64 bits) | | Import Route Target (64 bits) |
+--------------------------------+ +--------------------------------+
| Route Type (8 bits) | | Route Type (8 bits) |
+--------------------------------+ +--------------------------------+
| Host Address | | Host Address |
| (0, 32, 48 or 128 bits) | | (0, 32, 48, or 128 bits) |
| .... | .... |
+--------------------------------+ +--------------------------------+
Figure 1: CP-ORF Type-specific Encoding Figure 1: CP-ORF Type-Specific Encoding
The CP-ORF recipient uses the following fields to select routes The CP-ORF recipient uses the following fields to select routes
matching the CP-ORF: matching the CP-ORF:
o Sequence: Relative position of CP-ORF entry among other CP-ORF o Sequence: the relative position of a CP-ORF entry among other
entries CP-ORF entries
o Minlen: Minimum length of selected route (measured in bits) o Minlen: the minimum length of the selected route (measured in
bits)
o Maxlen: Maximum length of selected route (measured in bits) o Maxlen: the maximum length of the selected route (measured in
bits)
o VPN Route Target : VPN Route Target carried by selected route o VPN Route Target: the VPN Route Target carried by the selected
route
o Route Type: Type of selected route o Route Type: the type of the selected route
o Host Address: Address covered by selected route o Host Address: the address covered by the selected route
See Section 3 for details. See Section 3 for details.
The CP-ORF recipient marks routes that match CP-ORF with the Import The CP-ORF recipient marks routes that match CP-ORF with the Import
Route Target before advertising those routes to the CP-ORF Route Target before advertising those routes to the CP-ORF
originator. See Section 3 for details. originator. See Section 3 for details.
If the ROUTE-REFRESH AFI is equal to IPv4: If the ROUTE-REFRESH AFI is equal to IPv4,
o The value of Minlen MUST be less than or equal to 32 o the value of Minlen MUST be less than or equal to 32;
o The value of Maxlen MUST be less than or equal to 32 o the value of Maxlen MUST be less than or equal to 32;
o The value of Minlen MUST be less than or equal to the value of o the value of Minlen MUST be less than or equal to the value of
Maxlen Maxlen;
o The value of Route Type MUST be 0 (i.e., RESERVED) o the value of Route Type MUST be 0 (i.e., RESERVED); and
o The Host Address MUST contain exactly 32 bits o the Host Address MUST contain exactly 32 bits.
If the ROUTE-REFRESH AFI is equal to IPv6: If the ROUTE-REFRESH AFI is equal to IPv6,
o The value of Minlen MUST be less than or equal to 128 o the value of Minlen MUST be less than or equal to 128;
o The value of Maxlen MUST be less than or equal to 128 o the value of Maxlen MUST be less than or equal to 128;
o The value of Minlen MUST be less than or equal to the value of o the value of Minlen MUST be less than or equal to the value of
Maxlen Maxlen;
o The value of Route Type MUST be 0 (i.e., RESERVED) o the value of Route Type MUST be 0 (i.e., RESERVED); and
o The Host Address MUST contain exactly 128 bits o the Host Address MUST contain exactly 128 bits.
If the ROUTE-REFRESH AFI is equal to L2VPN, the value of Route Type If the ROUTE-REFRESH AFI is equal to L2VPN, the value of Route Type
MUST be one of the following values, taken from IANA EVPN Registry MUST be one of the following values taken from the IANA EVPN Registry
[IANA.EVPN]: [IANA.EVPN]:
o 1 - Ethernet Autodiscovery Route o 1 - Ethernet Autodiscovery Route
o 2 - MAC/IP Advertisement Route o 2 - MAC/IP Advertisement Route
o 3 - Inclusive Multicast Route o 3 - Inclusive Multicast Route
o 4 - Ethernet Segment Route o 4 - Ethernet Segment
If the ROUTE-REFRESH AFI is equal to L2VPN and the value of Route If the ROUTE-REFRESH AFI is equal to L2VPN and the value of Route
Type is equal to Ethernet Autodiscovery Route, Inclusive Multicast Type is equal to Ethernet Autodiscovery Route, Inclusive Multicast
Route, or Ethernet Segment Route: Route, or Ethernet Segment,
o The value of Minlen MUST be equal to 0 o the value of Minlen MUST be equal to 0;
o The value of Maxlen MUST be equal to 0 o the value of Maxlen MUST be equal to 0; and
o The Host Address MUST be absent (i.e., contain 0 bits) o the Host Address MUST be absent (i.e., contain 0 bits).
If the ROUTE-REFRESH AFI is equal to L2VPN and the value of Route If the ROUTE-REFRESH AFI is equal to L2VPN and the value of Route
Type is equal to MAC/IP Advertisement Route: Type is equal to MAC/IP Advertisement Route,
o The value of Minlen MUST be less than or equal to 48 o the value of Minlen MUST be less than or equal to 48;
o The value of Maxlen MUST be less than or equal to 48 o the value of Maxlen MUST be less than or equal to 48;
o The value of Minlen MUST be less than or equal to the value of o the value of Minlen MUST be less than or equal to the value of
Maxlen Maxlen; and
o The Host Address MUST contain exactly 48 bits. o the Host Address MUST contain exactly 48 bits.
3. Processing Rules 3. Processing Rules
According to [RFC4271], every BGP speaker maintains a single Loc-RIB. According to [RFC4271], every BGP speaker maintains a single Loc-RIB.
For each of its peers, the BGP speaker also maintains an Outbound For each of its peers, the BGP speaker also maintains an Outbound
Filter and an Adj-RIB-Out. The Outbound Filter defines policy that Filter and an Adj-RIB-Out. The Outbound Filter defines policy that
determines which Loc-RIB entries are processed into the corresponding determines which Loc-RIB entries are processed into the corresponding
Adj-RIB-Out. Mechanisms such as RT-Contstrain [RFC4684] and ORF Adj-RIB-Out. Mechanisms such as RT-Constrain [RFC4684] and ORF
[RFC5291] enable a router's peer to influence the Outbound Filter. [RFC5291] enable a router's peer to influence the Outbound Filter.
Therefore, the Outbound Filter for a given peer is constructed using Therefore, the Outbound Filter for a given peer is constructed using
a combination of the locally configured policy and the information a combination of the locally configured policy and the information
received via RT-Constrain and ORF from the peer. received via RT-Constrain and ORF from the peer.
Using this model we can describe the operations of CP-ORF as follows: Using this model, we can describe the operations of CP-ORF as
follows:
When a BGP speaker receives a ROUTE-REFRESH message that contains a When a BGP speaker receives a ROUTE-REFRESH message that contains a
CP-ORF, and that ROUTE-REFRESH message violates any of the encoding CP-ORF and that ROUTE-REFRESH message violates any of the encoding
rules specified in Section 2, the BGP speaker MUST ignore the entire rules specified in Section 2, the BGP speaker MUST ignore the entire
ROUTE-REFRESH message. It SHOULD also log the event. However, an ROUTE-REFRESH message. It SHOULD also log the event. However, an
implementation MAY apply logging thresholds to avoid excessive implementation MAY apply logging thresholds to avoid excessive
messaging or log file overflow. messaging or log file overflow.
Otherwise, the BGP speaker processes each CP-ORF entry as indicated Otherwise, the BGP speaker processes each CP-ORF entry as indicated
by the Action field. If the Action is equal to ADD, the BGP speaker by the Action field. If the Action is equal to ADD, the BGP speaker
adds the CP-ORF entry to the Outbound Filter associated with the peer adds the CP-ORF entry to the Outbound Filter associated with the peer
in the position specified by the Sequence field. If the Action is in the position specified by the Sequence field. If the Action is
equal to REMOVE, the BGP speaker removes the CP-ORF entry from the equal to REMOVE, the BGP speaker removes the CP-ORF entry from the
Outbound Filter. If the Action is equal to REMOVE-ALL, the BGP Outbound Filter. If the Action is equal to REMOVE-ALL, the BGP
speaker removes all CP-ORF entries from the Outbound Filter. speaker removes all CP-ORF entries from the Outbound Filter.
Whenever the BGP speaker applies an Outbound Filter to a route Whenever the BGP speaker applies an Outbound Filter to a route
contained in its Loc-RIB, it evaluates the route in terms of the CP- contained in its Loc-RIB, it evaluates the route in terms of the
ORF entries first. It then evaluates the route in terms of the CP-ORF entries first. It then evaluates the route in terms of the
remaining, non-CP-ORF entries. The rules for the former are remaining non-CP-ORF entries. The rules for the former are described
described below. The rules for the latter are outside the scope of below. The rules for the latter are outside the scope of this
this document. document.
The following route types can match a CP-ORF: The following route types can match a CP-ORF:
o IPv4-VPN o IPv4-VPN
o IPv6-VPN o IPv6-VPN
o L2VPN o L2VPN
In order for an IPv4-VPN route or IPv6-VPN route to match a CP-ORF, In order for an IPv4-VPN route or IPv6-VPN route to match a CP-ORF,
all of the following conditions MUST be true: all of the following conditions MUST be true:
o the route carries an RT whose value is the same as the CP-ORF VPN o the route carries an RT whose value is the same as the CP-ORF VPN
Route Target Route Target;
o the route prefix length is greater than or equal to the CP-ORF o the route prefix length is greater than or equal to the CP-ORF
Minlen plus 64 (i.e., the length of a VPN Route Distinguisher) Minlen plus 64 (i.e., the length of a VPN Route Distinguisher);
o the route prefix length is less than or equal to the CP-ORF Maxlen o the route prefix length is less than or equal to the CP-ORF Maxlen
plus 64 (i.e., the length of a VPN Route Distinguisher) plus 64 (i.e., the length of a VPN Route Distinguisher);
o ignoring the Route Distinguisher, the leading bits of the route o ignoring the Route Distinguisher, the leading bits of the route
prefix are identical to the leading bits of the CP-ORF Host prefix are identical to the leading bits of the CP-ORF Host
Address. CP-ORF Minlen defines the number of bits that must be Address, and CP-ORF Minlen defines the number of bits that must be
identical. identical; and
o Loc-RIB does not contain a more specific route that also satisfies o Loc-RIB does not contain a more specific route that also satisfies
all of the above listed conditions. all of the above listed conditions.
The BGP speaker ignores Route Distinguishers when determining whether The BGP speaker ignores Route Distinguishers when determining whether
a prefix matches a host address. For example, assume that a CP-ORF a prefix matches a host address. For example, assume that a CP-ORF
carries the following information: carries the following information:
o Minlen equal to 1 o Minlen equal to 1
o Maxlen equal to 32 o Maxlen equal to 32
o Host Address equal to 192.0.2.1 o Host Address equal to 192.0.2.1
Assume also that Loc-RIB contains routes for the following IPv4-VPN Assume also that Loc-RIB contains routes for the following IPv4-VPN
prefixes, and that all of these routes carry an RT whose value is the prefixes and that all of these routes carry an RT whose value is the
same as the CP-ORF VPN Route Target: same as the CP-ORF VPN Route Target:
o 1:0.0.0.0/64. o 1:0.0.0.0/64.
o 2:192.0.2.0/88 o 2:192.0.2.0/88
o 3:192.0.2.0/89 o 3:192.0.2.0/89
Only the prefix 3:192.0.2.0/89 matches the CP-ORF. The prefix Only the prefix 3:192.0.2.0/89 matches the CP-ORF. The prefix
1:0.0.0.0/64 does not match, because its length (64) is less than the 1:0.0.0.0/64 does not match, because its length (64) is less than the
CP-ORF Minlen (1) plus the length of an L3VPN Route Distinguisher CP-ORF Minlen (1) plus the length of an L3VPN Route Distinguisher
(64). If Loc-RIB did not contain the prefix 3:192.0.2.0/89, (64). If Loc-RIB did not contain the prefix 3:192.0.2.0/89,
2:192.0.2.0/88 would match the CP-ORF. However, because Loc-RIB also 2:192.0.2.0/88 would match the CP-ORF. However, because Loc-RIB also
contains a more specific covering route (3:192.0.2.0/89), contains a more specific covering route (3:192.0.2.0/89),
2:192.0.2.0/88 does not match. Only 3:192.0.2.0/89 satisfies all of 2:192.0.2.0/88 does not match. Only 3:192.0.2.0/89 satisfies all of
the above listed match criteria. Note that the matching algorithm the above listed match criteria. Note that the matching algorithm
ignored Route Distinguishers. ignored Route Distinguishers.
skipping to change at page 8, line 31 skipping to change at page 9, line 17
(64). If Loc-RIB did not contain the prefix 3:192.0.2.0/89, (64). If Loc-RIB did not contain the prefix 3:192.0.2.0/89,
2:192.0.2.0/88 would match the CP-ORF. However, because Loc-RIB also 2:192.0.2.0/88 would match the CP-ORF. However, because Loc-RIB also
contains a more specific covering route (3:192.0.2.0/89), contains a more specific covering route (3:192.0.2.0/89),
2:192.0.2.0/88 does not match. Only 3:192.0.2.0/89 satisfies all of 2:192.0.2.0/88 does not match. Only 3:192.0.2.0/89 satisfies all of
the above listed match criteria. Note that the matching algorithm the above listed match criteria. Note that the matching algorithm
ignored Route Distinguishers. ignored Route Distinguishers.
In order for an EVPN route to match a CP-ORF, all of the following In order for an EVPN route to match a CP-ORF, all of the following
conditions MUST be true: conditions MUST be true:
o the EVPN route type is equal to the CP-ORF Route Type o the EVPN route type is equal to the CP-ORF Route Type; and
o the route carries an RT whose value is equal to the CP-ORF VPN o the route carries an RT whose value is equal to the CP-ORF VPN
Route Target Route Target.
In addition, if the CP-ORF Route Type is equal to MAC/IP In addition, if the CP-ORF Route Type is equal to MAC/IP
Advertisement Route, the following conditions also MUST be true: Advertisement Route, the following conditions also MUST be true:
o the EVPN Route MAC Address Length is greater than or equal to the o the EVPN Route MAC Address Length is greater than or equal to the
CP-ORF Minlen plus 64 (i.e., the length of a VPN Route CP-ORF Minlen plus 64 (i.e., the length of a VPN Route
Distinguisher) Distinguisher);
o the EVPN Route MAC Address Length is less than or equal to the CP- o the EVPN Route MAC Address Length is less than or equal to the CP-
ORF Maxlen plus 64 (i.e., the length of a VPN Route Distinguisher) ORF Maxlen plus 64 (i.e., the length of a VPN Route
Distinguisher); and
o ignoring the Route Distinguisher, the leading bits of the EVPN o ignoring the Route Distinguisher, the leading bits of the EVPN
Route MAC Address are identical to the leading bits of the CP-ORF Route MAC Address are identical to the leading bits of the CP-ORF
Host Address. CP-ORF Minlen defines the number of bits that must Host Address. CP-ORF Minlen defines the number of bits that must
be identical. be identical.
If a route matches the selection criteria of a CP-ORF entry, and it If a route matches the selection criteria of a CP-ORF entry and it
does not violate any subsequent rule specified by the Outbound Filter does not violate any subsequent rule specified by the Outbound Filter
(e.g., rules that reflect local policy, or rules that are due to RT- (e.g., rules that reflect local policy or rules that are due to
Constrains), the BGP speaker places the route into the Adj-RIB-Out. RT-Constrains), the BGP speaker places the route into the Adj-RIB-
In Adj-RIB-Out, the BGP speaker adds the CP-ORF Import Route Target Out. In Adj-RIB-Out, the BGP speaker adds the CP-ORF Import Route
to the list of Route Targets that the route already carries. The BGP Target to the list of RTs that the route already carries. The BGP
speaker also adds a Transitive Opaque Extended Community [RFC4360] speaker also adds a Transitive Opaque Extended Community [RFC4360]
with subtype equal to CP-ORF (0x03). As a result of being placed in with the sub-type equal to CP-ORF (0x03). As a result of being
Adj-RIB-Out, the route is advertised to the peer associated with the placed in Adj-RIB-Out, the route is advertised to the peer associated
Adj-RIB-Out. with the Adj-RIB-Out.
Receiving CP-ORF entries with REMOVE or REMOVE-ALL Actions may cause Receiving CP-ORF entries with REMOVE or REMOVE-ALL Actions may cause
a route that has previously been installed in a particular Adj-RIB- a route that has previously been installed in a particular Adj-RIB-
Out be excluded from that Adj-RIB-Out. In this case, as specified in Out to be excluded from that Adj-RIB-Out. In this case, as specified
[RFC4271], "the previously advertised route in that Adj-RIB-Out MUST in [RFC4271], "the previously advertised route in that Adj-RIB-Out
be withdrawn from service by means of an UPDATE message". MUST be withdrawn from service by means of an UPDATE message".
RFC 5291 states that a BGP speaker should respond to a ROUTE REFRESH RFC 5291 states that a BGP speaker should respond to a ROUTE REFRESH
message as follows: message as follows:
"If the When-to-refresh indicates IMMEDIATE, then after processing If the When-to-refresh indicates IMMEDIATE, then after processing
all the ORF entries carried in the message the speaker re-advertises all the ORF entries carried in the message the speaker
to the peer routes from the Adj-RIB-Out associated with the peer that re-advertises to the peer routes from the Adj-RIB-Out associated
have the same AFI/SAFI as what is carried in the message, and taking with the peer that have the same AFI/SAFI as what is carried in
into account all the ORF entries for that AFI/SAFI received from the the message, and taking into account all the ORF entries for that
peer. The speaker MUST re-advertise all the routes that have been AFI/SAFI received from the peer. The speaker MUST re-advertise
affected by the ORF entries carried in the message, but MAY also re- all the routes that have been affected by the ORF entries carried
advertise the routes that have not been affected by the ORF entries in the message, but MAY also re-advertise the routes that have not
carried in the message." been affected by the ORF entries carried in the message.
When the ROUTE-REFRESH message includes only CP-ORF entries, the BGP When the ROUTE-REFRESH message includes only CP-ORF entries, the BGP
speaker MUST re-advertise routes that have been affected by these CP- speaker MUST re-advertise routes that have been affected by these
ORF entries. It is RECOMMENDED not to re-advertise the routes that CP-ORF entries. It is RECOMMENDED not to re-advertise the routes
have not been affected by the CP-ORF entries. that have not been affected by the CP-ORF entries.
The behavior when the ROUTE-REFRESH message includes one or more CP- When the ROUTE-REFRESH message includes one or more CP-ORF entries
ORF entries and one or more ORF entries of a different type remains and one or more ORF entries of a different type, the behavior remains
unchanged from that described in RFC 5291. unchanged from that described in RFC 5291.
4. Applicability In Virtual Hub-and-Spoke VPNs 4. Applicability in Virtual Hub-and-Spoke VPNs
In a Virtual Hub-and-Spoke environment, VPN sites are attached to In a Virtual Hub-and-Spoke environment, VPN sites are attached to PE
Provider Edge (PE) routers. For a given VPN, a PE router acts in routers. For a given VPN, a PE router acts in exactly one of the
exactly one of the following roles: following roles:
o As neither a V-hub nor a V-Spoke o as a V-hub
o As a V-hub o as a V-spoke
o As a V-spoke
o as neither a V-hub nor a V-spoke
To illustrate CP-ORF operation in conjunction with Virtual Hub-and- To illustrate CP-ORF operation in conjunction with Virtual Hub-and-
Spoke assume the following: Spoke, assume the following:
o One of the sites in a particular VPN, RED-VPN, is connected to a o One of the sites in a particular VPN, RED-VPN, is connected to a
PE that acts as neither a V-hub nor a V-Spoke for RED-VPN. We PE that acts as neither a V-hub nor a V-spoke for RED-VPN. We
refer to this PE as PE1. refer to this PE as PE1.
o Another site in RED-VPN is connected to another PE, and that PE o Another site in RED-VPN is connected to another PE, and that PE
acts as a V-hub for RED-VPN. We refer to this PE as V-hub1. acts as a V-hub for RED-VPN. We refer to this PE as V-hub1.
o Yet another site in RED-VPN is connected to another PE, and that o Yet another site in RED-VPN is connected to another PE, and that
PE acts as a V-spoke for RED-VPN. We refer to this PE as PE acts as a V-spoke for RED-VPN. We refer to this PE as
V-spoke1. V-spoke1.
All of these PEs advertise RED-VPN routes to a route reflector (RR). All of these PEs advertise RED-VPN routes to a Route Reflector (RR).
They mark these routes with a route target, which we will call RT- They mark these routes with an RT, which we will call RT-RED. In
RED. In particular, PE1 advertises a RED-VPN route to a prefix that particular, PE1 advertises a RED-VPN route to a prefix that we will
we will call P. P covers a host address, that we will call H. call P. P covers a host address that we will call H.
For the purpose of illustration also assume that the PEs and the RRs For the purpose of illustration, also assume that the PEs and the RRs
use Route Target Constraint [RFC4684]. use RT-Constrain [RFC4684].
V-hub1 serves the RED-VPN. Therefore, V-hub1 advertises a VPN IP V-hub1 serves the RED-VPN. Therefore, V-hub1 advertises a VPN-IP
default route for the RED-VPN to the RR, carrying the route target default route for the RED-VPN to the RR, carrying the route target
RT-RED-FROM-HUB1. RT-RED-FROM-HUB1.
V-spoke1 establishes a BGP session with the RR, negotiating the CP- V-spoke1 establishes a BGP session with the RR, negotiating the
ORF capability, as well as the Multiprotocol Extensions Capability CP-ORF capability as well as the Multiprotocol Extensions capability
[RFC4760]. Upon establishment of the BGP session, the RR does not [RFC4760]. Upon establishment of the BGP session, the RR does not
advertise any routes to V-spoke1. The RR will not advertise any advertise any routes to V-spoke1. The RR will not advertise any
routes until it receives either a ROUTE-REFRESH message or a BGP routes until it receives either a ROUTE-REFRESH message or a BGP
UPDATE message containing a Route Target Membership NLRI [RFC4684]. UPDATE message containing a Route Target Membership Network Layering
Reachability Information (NLRI) [RFC4684].
Immediately after the BGP session is established, V-spoke1 sends the Immediately after the BGP session is established, V-spoke1 sends the
RR a BGP UPDATE message containing a Route Target Membership NLRI. RR a BGP UPDATE message containing a Route Target Membership NLRI.
The Route Target Membership NLRI specifies RT-RED-FROM-HUB1 as its The Route Target Membership NLRI specifies RT-RED-FROM-HUB1 as its
route target. In response to the BGP-UPDATE message, the RR RT. In response to the BGP-UPDATE message, the RR advertises the VPN
advertises the VPN IP default route for the RED-VPN to V-spoke1. IP default route for the RED-VPN to V-spoke1. This route carries the
This route carries the route target RT-RED-FROM-HUB1. V-spoke1 route target RT-RED-FROM-HUB1. V-spoke1 subjects this route to its
subjects this route to its import policy and accepts it because it import policy and accepts it because it carries the route target
carries the route target RT-RED-FROM-HUB1. RT-RED-FROM-HUB1.
Now, V-spoke1 begins normal operation, sending all of its RED-VPN Now, V-spoke1 begins normal operation, sending all of its RED-VPN
traffic through V-hub1. At some point, V-spoke1 determines that it traffic through V-hub1. At some point, V-spoke1 determines that it
might benefit from a more direct route to H. (Criteria by which might benefit from a more direct route to H. (Note that criteria by
V-spoke1 determines that it needs a more direct route to H are beyond which V-spoke1 determines that it needs a more direct route to H are
the scope of this document.) beyond the scope of this document.)
In order to discover a more direct route, V-spoke1 assigns a unique In order to discover a more direct route, V-spoke1 assigns a unique
numeric identifier to H. V-spoke1 then sends a ROUTE-REFRESH message numeric identifier to H. V-spoke1 then sends a ROUTE-REFRESH message
to the RR, containing the following information: to the RR, which contains the following information:
o AFI is equal to IPv4 or IPv6, as appropriate o AFI is equal to IPv4 or IPv6, as appropriate
o SAFI is equal to "MPLS-labeled VPN address" o SAFI is equal to "MPLS-labeled VPN address"
o When-to-refresh is equal IMMEDIATE o When-to-refresh is equal to IMMEDIATE
o Action is equal to ADD o Action is equal to ADD
o Match is equal to PERMIT o Match is equal to PERMIT
o ORF Type is equal to CP-ORF o ORF Type is equal to CP-ORF
o CP-ORF Sequence is equal to the identifier associated with H o CP-ORF Sequence is equal to the identifier associated with H
o CP-ORF Minlen is equal to 1 o CP-ORF Minlen is equal to 1
o CP-ORF Maxlen is equal to 32 or 128, as appropriate o CP-ORF Maxlen is equal to 32 or 128, as appropriate
o CP-ORF VPN Route Target is equal to RT-RED o CP-ORF VPN Route Target is equal to RT-RED
o CP-ORF Import Route Target is equal to RT-RED-FROM-HUB1 o CP-ORF Import Route Target is equal to RT-RED-FROM-HUB1
o CP-ORF Route Type is equal to 0 (i.e., undefined) o CP-ORF Route Type is equal to 0 (i.e., undefined)
o CP-ORF Host Address is equal H o CP-ORF Host Address is equal to H
Upon receipt of the ROUTE-REFRESH message, the RR MUST ensure that it Upon receipt of the ROUTE-REFRESH message, the RR MUST ensure that it
carries all routes belonging to the RED-VPN. In at least one special carries all routes belonging to the RED-VPN. In at least one special
case, where all of the RR clients are V-spokes and none of the RR case, where all of the RR clients are V-spokes and none of the RR
clients are V-hubs, the RR will lack some or all of the required RED- clients are V-hubs, the RR will lack some or all of the required
VPN routes. So, the RR sends a BGP UPDATE message containing a Route RED-VPN routes. So, the RR sends a BGP UPDATE message containing a
Target Membership NLRI for VPN-RED to all of its peers. This causes Route Target Membership NLRI for VPN-RED to all of its peers. This
the peers to advertise VPN-RED routes to the RR, if they have not causes the peers to advertise VPN-RED routes to the RR if they have
done so already. not done so already.
Next, the RR adds the received CP-ORF to the Outbound Filter Next, the RR adds the received CP-ORF to the Outbound Filter
associated with V-spoke1. Using the procedures in Section 3, the RR associated with V-spoke1. Using the procedures in Section 3, the RR
determines whether any of the routes in its Loc-RIB satisfy the determines whether any of the routes in its Loc-RIB satisfy the
selection criteria of the newly updated Outbound Filter. If any selection criteria of the newly updated Outbound Filter. If any
routes satisfy the match criteria, they are added to the Adj-RIB-Out routes satisfy the match criteria, they are added to the Adj-RIB-Out
associated with V-spoke1. In Adj-RIB-Out, the RR adds RT-RED-FROM- associated with V-spoke1. In Adj-RIB-Out, the RR adds
HUB1 to the list of Route Targets that the route already carries. RT-RED-FROM-HUB1 to the list of RTs that the route already carries.
The RR also adds a Transitive Opaque Extended Community [RFC4360] The RR also adds a Transitive Opaque Extended Community [RFC4360]
with subtype equal to CP-ORF. Finally, RR advertises the newly added with the sub-type equal to CP-ORF. Finally, RR advertises the newly
routes to V-spoke1. In this example, the RR advertises P to V-Spoke1 added routes to V-spoke1. In this example, the RR advertises P to
with a next-hop of PE1. V-spoke1 with a next-hop of PE1.
V-spoke1 subjects the advertised routes to its import policy and V-spoke1 subjects the advertised routes to its import policy and
accepts them because they carry the route target RT-RED-FROM-HUB1. accepts them because they carry the route target RT-RED-FROM-HUB1.
V-spoke1 may repeat this process whenever it discovers another flow V-spoke1 may repeat this process whenever it discovers another flow
that might benefit from a more direct route to its destination. that might benefit from a more direct route to its destination.
4.1. Multicast Considerations 4.1. Multicast Considerations
When applying Multicast VPN [RFC6513][RFC6514] procedures, routes When applying Multicast VPN [RFC6513] [RFC6514] procedures, routes
bearing a Transitive Opaque Extended Community [RFC4360] with subtype bearing a Transitive Opaque Extended Community [RFC4360] with the
equal to CP-ORF MUST NOT be used to determine Eligible Upstream sub-type equal to CP-ORF MUST NOT be used to determine Eligible
Multicast Hops (UMH). Upstream Multicast Hops (UMH).
5. Applicability In BGP/MPLS Ethernet VPN (EVPN) 5. Applicability in BGP/MPLS Ethernet VPN (EVPN)
In a EVPN environment, CE devices are attached to Provider Edge (PE) In an EVPN environment, Customer Edge (CE) devices are attached to PE
routers. A CE can be a host, a router or a switch. For a given EVPN routers. A CE can be a host, a router, or a switch. For a given
Instance (EVI), a PE router acts in exactly one of the following EVI, a PE router acts in exactly one of the following roles:
roles:
o As neither a Default MAC Gateway (DMG) nor a Spoke o as a DMG
o As a DMG o as a Spoke
o As a Spoke o as neither a DMG nor a Spoke
To illustrate CP-ORF operation in the EVPN environment assume the To illustrate CP-ORF operation in the EVPN environment, assume the
following: following:
o A CE device in a particular EVI, RED-EVI, is connected to a PE o A CE device in a particular EVI, RED-EVI, is connected to a PE
that acts as neither a DMG nor a Spoke for RED-EVI. We refer to that acts as neither a DMG nor a Spoke for RED-EVI. We refer to
this PE as PE1. this PE as PE1.
o Another CE device in RED-EVI is connected to another PE, and that o Another CE device in RED-EVI is connected to another PE, and that
PE acts as a DMG for RED-EVI. We refer to this PE as DMG1. PE acts as a DMG for RED-EVI. We refer to this PE as DMG1.
o Yet another CE device in RED-EVI is connected to another PE, and o Yet another CE device in RED-EVI is connected to another PE, and
that PE acts as a Spoke for RED-EVI. We refer to this PE as that PE acts as a Spoke for RED-EVI. We refer to this PE as
Spoke1. Spoke1.
All of these PEs advertise RED-EVI routes to a RR. They mark these All of these PEs advertise RED-EVI routes to a RR. They mark these
routes with a route target, which we will call RT-RED. In routes with an RT, which we will call RT-RED. In particular, PE1
particular, PE1 advertises a RED-EVI route to a MAC Address that we advertises a RED-EVI route to a MAC Address that we will call M.
will call M.
The RED-EVI VRFs on all of these PEs are provisioned to import EVPN The RED-EVI VPN Routing and Forwarding tables (VRFs) on all of these
routes that carry RT-RED. PEs are provisioned to import EVPN routes that carry RT-RED.
Since DMG1 acts as a DMG for RED-EVI, DMG1 advertises a Unknown MAC Since DMG1 acts as a DMG for RED-EVI, DMG1 advertises a UMR for the
Route (UMR) for the RED-EVI to the RR, carrying the route target RT- RED-EVI to the RR, carrying the route target RT-RED. The UMR is
RED. The UMR is characterized as follows: characterized as follows:
o EVPN Route Type is equal to MAC/IP Advertisement Route o EVPN Route Type is equal to MAC/IP Advertisement Route
o MAC address length is equal to 0 o MAC address length is equal to 0
o IP address length is equal to 0 o IP address length is equal to 0
Spoke1 establishes a BGP session with the RR, negotiating the CP-ORF Spoke1 establishes a BGP session with the RR, negotiating the CP-ORF
capability, as well as the Multiprotocol Extensions Capability capability as well as the Multiprotocol Extensions capability
[RFC4760]. Upon establishment of the BGP session, the RR does not [RFC4760]. Upon establishment of the BGP session, the RR does not
advertise any routes to Spoke1. The RR will not advertise any routes advertise any routes to Spoke1. The RR will not advertise any routes
until it receives a ROUTE-REFRESH message. until it receives a ROUTE-REFRESH message.
Immediately after the BGP session is established, Spoke1 sends the RR Immediately after the BGP session is established, Spoke1 sends the RR
a ROUTE REFRESH message containing the following information: a ROUTE REFRESH message containing the following information:
o AFI is equal to L2VPN o AFI is equal to L2VPN
o SAFI is equal to BGP EVPN o SAFI is equal to BGP EVPN
o When-to-refresh is equal IMMEDIATE o When-to-refresh is equal to IMMEDIATE
o Action is equal to ADD o Action is equal to ADD
o Match is equal to PERMIT o Match is equal to PERMIT
The ROUTE REFRESH message also contains four ORF entries. The first The ROUTE REFRESH message also contains four ORF entries. The first
ORF entry contains the following information: ORF entry contains the following information:
o ORF Type is equal to CP-ORF o ORF Type is equal to CP-ORF
o CP-ORF Sequence is equal 1 o CP-ORF Sequence is equal to 1
o CP-ORF Minlen is equal to 0 o CP-ORF Minlen is equal to 0
o CP-ORF Maxlen is equal to 0 o CP-ORF Maxlen is equal to 0
o CP-ORF VPN Route Target is equal to RT-RED o CP-ORF VPN Route Target is equal to RT-RED
o CP-ORF Import Route Target is equal to RT-RED o CP-ORF Import Route Target is equal to RT-RED
o CP-ORF Route Type is equal to 1 (Ethernet Autodiscovery Route) o CP-ORF Route Type is equal to 1 (Ethernet Autodiscovery Route)
The second ORF entry contains the following information: The second ORF entry contains the following information:
o ORF Type is equal to CP-ORF o ORF Type is equal to CP-ORF
o CP-ORF Sequence is equal 2 o CP-ORF Sequence is equal to 2
o CP-ORF Minlen is equal to 0 o CP-ORF Minlen is equal to 0
o CP-ORF Maxlen is equal to 0 o CP-ORF Maxlen is equal to 0
o CP-ORF VPN Route Target is equal to RT-RED o CP-ORF VPN Route Target is equal to RT-RED
o CP-ORF Import Route Target is equal to RT-RED o CP-ORF Import Route Target is equal to RT-RED
o CP-ORF Route Type is equal to 2 (MAC/IP Advertisement Route) o CP-ORF Route Type is equal to 2 (MAC/IP Advertisement Route)
The third ORF entry contains the following information: The third ORF entry contains the following information:
o ORF Type is equal to CP-ORF o ORF Type is equal to CP-ORF
o CP-ORF Sequence is equal 3 o CP-ORF Sequence is equal to 3
o CP-ORF Minlen is equal to 0 o CP-ORF Minlen is equal to 0
o CP-ORF Maxlen is equal to 0 o CP-ORF Maxlen is equal to 0
o CP-ORF VPN Route Target is equal to RT-RED o CP-ORF VPN Route Target is equal to RT-RED
o CP-ORF Import Route Target is equal to RT-RED o CP-ORF Import Route Target is equal to RT-RED
o CP-ORF Route Type is equal to 3 (Inclusive Multicast Route) o CP-ORF Route Type is equal to 3 (Inclusive Multicast Route)
The fourth ORF entry contains the following information: The fourth ORF entry contains the following information:
o ORF Type is equal to CP-ORF o ORF Type is equal to CP-ORF
o CP-ORF Sequence is equal 4 o CP-ORF Sequence is equal to 4
o CP-ORF Minlen is equal to 0 o CP-ORF Minlen is equal to 0
o CP-ORF Maxlen is equal to 0 o CP-ORF Maxlen is equal to 0
o CP-ORF VPN Route Target is equal to RT-RED o CP-ORF VPN Route Target is equal to RT-RED
o CP-ORF Import Route Target is equal to RT-RED
o CP-ORF Route Type is equal to 4 (Ethernet Segment Route) o CP-ORF Import Route Target is equal to RT-RED
o CP-ORF Route Type is equal to 4 (Ethernet Segment)
In response to the ROUTE REFRESH message, the RR advertises the In response to the ROUTE REFRESH message, the RR advertises the
following to V-spoke1: following to V-spoke1:
o All Ethernet Autodiscovery Routes belonging to RED-EVI o All Ethernet Autodiscovery Routes belonging to RED-EVI
o A UMR advertised by DMG1 and belonging to RED-EVI o A UMR advertised by DMG1 and belonging to RED-EVI
o All Inclusive Multicast Routes belonging to RED-EVI o All Inclusive Multicast Routes belonging to RED-EVI
o All Ethernet Segment Routes belonging to RED-EVI o All Ethernet Segment Routes belonging to RED-EVI
All of these routes carries the route target RT-RED. Spoke1 subjects All of these routes carry the route target RT-RED. Spoke1 subjects
these routes to its import policy and accepts them because they carry these routes to its import policy and accepts them because they carry
the route target RT-RED. the route target RT-RED.
Now, Spoke1 begins normal operation, sending all of its RED-VPN Now, Spoke1 begins normal operation, sending all of its RED-VPN
traffic through DMG1. At some point, Spoke1 determines that it might traffic through DMG1. At some point, Spoke1 determines that it might
benefit from a more direct route to M. (Criteria by which Spoke1 benefit from a more direct route to M. (Note that criteria by which
determines that it needs a more direct route to M are beyond the Spoke1 determines that it needs a more direct route to M are beyond
scope of this document.) the scope of this document.)
In order to discover a more direct route, Spoke1 assigns a unique In order to discover a more direct route, Spoke1 assigns a unique
numeric identifier to M. V-spoke1 then sends a ROUTE-REFRESH message numeric identifier to M. V-spoke1 then sends a ROUTE-REFRESH message
to the RR, containing the following information: to the RR, containing the following information:
o AFI is equal to L2VPN o AFI is equal to L2VPN
o SAFI is equal to BGP EVPN o SAFI is equal to BGP EVPN
o When-to-refresh is equal IMMEDIATE o When-to-refresh is equal to IMMEDIATE
o Action is equal to ADD o Action is equal to ADD
o Match is equal to PERMIT o Match is equal to PERMIT
o ORF Type is equal to CP-ORF o ORF Type is equal to CP-ORF
o CP-ORF Sequence is equal to the identifier associated with M o CP-ORF Sequence is equal to the identifier associated with M
o CP-ORF Minlen is equal to 1 o CP-ORF Minlen is equal to 1
o CP-ORF Maxlen is equal to 48 o CP-ORF Maxlen is equal to 48
o CP-ORF VPN Route Target is equal to RT-RED o CP-ORF VPN Route Target is equal to RT-RED
o CP-ORF Import Route Target is equal to RT-RED
o CP-ORF Import Route Target is equal to RT-RED
o CP-ORF Route Type is equal to 2 (i.e., MAC/IP Advertisement Route) o CP-ORF Route Type is equal to 2 (i.e., MAC/IP Advertisement Route)
o CP-ORF Host Address is equal M o CP-ORF Host Address is equal to M
Next, the RR adds the received CP-ORF to the Outbound Filter Next, the RR adds the received CP-ORF to the Outbound Filter
associated with Spoke1. Using the procedures in Section 3, the RR associated with Spoke1. Using the procedures in Section 3, the RR
determines whether any of the routes in its Loc-RIB satisfy the determines whether any of the routes in its Loc-RIB satisfy the
selection criteria of the newly updated Outbound Filter. If any selection criteria of the newly updated Outbound Filter. If any
routes satisfy the match criteria, they are added to the Adj-RIB-Out routes satisfy the match criteria, they are added to the Adj-RIB-Out
associated with Spoke1. The RR adds a Transitive Opaque Extended associated with Spoke1. The RR adds a Transitive Opaque Extended
Community [RFC4360] with subtype equal to CP-ORF. Note that as these Community [RFC4360] with the sub-type equal to CP-ORF. Note that as
routes are added to the Adj-RIB-Out, the RR does not change the list these routes are added to the Adj-RIB-Out, the RR does not change the
of Route Targets that the route already carries. Finally, RR list of RTs that the route already carries. Finally, RR advertises
advertises the newly added routes to V-spoke1. In this example, the the newly added routes to V-spoke1. In this example, the RR
RR advertises M to V-Spoke1 with a next-hop of PE1. advertises M to V-spoke1 with a next-hop of PE1.
Spoke1 subjects the advertised routes to its import policy and Spoke1 subjects the advertised routes to its import policy and
accepts them because they carry the route target RT-RED. accepts them because they carry the route target RT-RED.
Spoke1 may repeat this process whenever it discovers another flow Spoke1 may repeat this process whenever it discovers another flow
that might benefit from a more direct route to its destination. that might benefit from a more direct route to its destination.
Note that in general an EVI may have more than one DMG, in which case Note that, in general, an EVI may have more than one DMG, in which
each spoke would receive a UMR from each of them. The spoke should case each spoke would receive a UMR from each of them. The spoke
follow its local route selection procedures to select one of them as should follow its local route selection procedures to select one of
the "best", and use the selected one. them as the "best" and use the selected one.
6. Clean-up 6. Clean-up
Each CP-ORF consumes memory and compute resources on the device that Each CP-ORF consumes memory and compute resources on the device that
supports it. Therefore, in order to obtain optimal performance, BGP supports it. Therefore, in order to obtain optimal performance, BGP
speakers periodically evaluate all CP-ORFs that they have originated speakers periodically evaluate all CP-ORFs that they have originated
and remove unneeded CP-ORFs. The criteria by which a BGP speaker and remove unneeded CP-ORFs. The criteria by which a BGP speaker
identifies unneeded CP-ORF entries is a matter of local policy, and identifies unneeded CP-ORF entries is a matter of local policy and is
is beyond the scope of this document. beyond the scope of this document.
7. IANA Considerations 7. IANA Considerations
This memo uses code points from the first-come-first-served range of This memo uses code points from the First Come First Served [RFC5226]
the following registries: range of the following registries:
+-----------------------------------------------+---------------+ +------------------------------------------------+---------------+
| Registry | Code Point | | Registry | Code Point |
+-----------------------------------------------+---------------+ +------------------------------------------------+---------------+
| BGP Outbound Route Filtering (ORF) Types | CP-ORF (65) | | BGP Outbound Route Filtering (ORF) Types | CP-ORF (65) |
| Transitive Opaque Extended Community Sub-Type | CP-ORF (0x03) | | Transitive Opaque Extended Community Sub-Types | CP-ORF (0x03) |
+-----------------------------------------------+---------------+ +------------------------------------------------+---------------+
IANA is requested to update the above mentioned registry entries so IANA has updated the above-mentioned registry entries so that they
that they include a stable reference to this memo. reference this memo.
8. Security Considerations 8. Security Considerations
Each CP-ORF consumes memory and compute resources on the device that Each CP-ORF consumes memory and compute resources on the device that
supports it. Therefore, a device supporting CP-ORF takes the supports it. Therefore, a device supporting CP-ORF takes the
following steps to protect itself from oversubscription: following steps to protect itself from oversubscription:
o When negotiating the ORF capability, advertise willingness to o When negotiating the ORF capability, advertise willingness to
receive the CP-ORF only to known, trusted iBGP peers. See receive the CP-ORF only to known, trusted Internal BGP (iBGP)
Section 5 of RFC 5291 for negotiation details. peers. See Section 5 of RFC 5291 for negotiation details.
o Enforce a per-peer limit on the number of CP-ORFs that can be o Enforce a per-peer limit on the number of CP-ORFs that can be
installed at any given time. Ignore all requests to add CP-ORFs installed at any given time. Ignore all requests to add CP-ORFs
beyond that limit beyond that limit
Security considerations for BGP are presented in RFC4271 while Security considerations for BGP are presented in [RFC4271] while
further security analysis of BGP is found in [RFC6952]. further security analysis of BGP is found in [RFC6952].
9. Contributors 9. References
The following individuals contributed to the development of this 9.1. Normative References
document:
o Yakov Rekhter [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
o Xiaohu Xu [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271, January
2006, <http://www.rfc-editor.org/info/rfc4271>.
10. Acknowledgements [RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended
Communities Attribute", RFC 4360, February 2006,
<http://www.rfc-editor.org/info/rfc4360>.
The authors wish to acknowledge Han Nguyen, James Uttaro and Alvaro [RFC4684] Marques, P., Bonica, R., Fang, L., Martini, L., Raszuk,
Retana for their comments and contributions. R., Patel, K., and J. Guichard, "Constrained Route
Distribution for Border Gateway Protocol/MultiProtocol
Label Switching (BGP/MPLS) Internet Protocol (IP) Virtual
Private Networks (VPNs)", RFC 4684, November 2006,
<http://www.rfc-editor.org/info/rfc4684>.
11. References [RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760, January
2007, <http://www.rfc-editor.org/info/rfc4760>.
11.1. Normative References [RFC5291] Chen, E. and Y. Rekhter, "Outbound Route Filtering
Capability for BGP-4", RFC 5291, August 2008,
<http://www.rfc-editor.org/info/rfc5291>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC6513] Rosen, E., Ed. and R. Aggarwal, Ed., "Multicast in MPLS/
Requirement Levels", BCP 14, RFC 2119, March 1997. BGP IP VPNs", RFC 6513, February 2012,
<http://www.rfc-editor.org/info/rfc6513>.
[RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway [RFC6514] Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP
Protocol 4 (BGP-4)", RFC 4271, January 2006. Encodings and Procedures for Multicast in MPLS/BGP IP
VPNs", RFC 6514, February 2012,
<http://www.rfc-editor.org/info/rfc6514>.
[RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended [RFC7024] Jeng, H., Uttaro, J., Jalil, L., Decraene, B., Rekhter,
Communities Attribute", RFC 4360, February 2006. Y., and R. Aggarwal, "Virtual Hub-and-Spoke in BGP/MPLS
VPNs", RFC 7024, October 2013,
<http://www.rfc-editor.org/info/rfc7024>.
[RFC4684] Marques, P., Bonica, R., Fang, L., Martini, L., Raszuk, [RFC7432] Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A.,
R., Patel, K., and J. Guichard, "Constrained Route Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-Based
Distribution for Border Gateway Protocol/MultiProtocol Ethernet VPN", RFC 7432, February 2015,
Label Switching (BGP/MPLS) Internet Protocol (IP) Virtual <http://www.rfc-editor.org/info/rfc7432>.
Private Networks (VPNs)", RFC 4684, November 2006.
[RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter, 9.2. Informative References
"Multiprotocol Extensions for BGP-4", RFC 4760, January
2007.
[RFC5291] Chen, E. and Y. Rekhter, "Outbound Route Filtering [IANA.AFI] IANA, "Address Family Numbers",
Capability for BGP-4", RFC 5291, August 2008. <http://www.iana.org/assignments/address-family-numbers>.
[RFC6513] Rosen, E. and R. Aggarwal, "Multicast in MPLS/BGP IP [IANA.EVPN] IANA, "Ethernet VPN (EVPN)",
VPNs", RFC 6513, February 2012. <http://www.iana.org/assignments/evpn>.
[RFC6514] Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP [IANA.SAFI] IANA, "Subsequent Address Family Identifiers (SAFI)
Encodings and Procedures for Multicast in MPLS/BGP IP Parameters",
VPNs", RFC 6514, February 2012. <http://www.iana.org/assignments/safi-namespace>.
[RFC7024] Jeng, H., Uttaro, J., Jalil, L., Decraene, B., Rekhter, [RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
Y., and R. Aggarwal, "Virtual Hub-and-Spoke in BGP/MPLS Networks (VPNs)", RFC 4364, February 2006,
VPNs", RFC 7024, October 2013. <http://www.rfc-editor.org/info/rfc4364>.
[RFC7432] Sajassi, A., Aggarwal, R., Bitar, N., Isaac, A., Uttaro, [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
J., Drake, J., and W. Henderickx, "BGP MPLS-Based Ethernet IANA Considerations Section in RFCs", BCP 26, RFC 5226,
VPN", RFC 7432, February 2015. May 2008, <http://www.rfc-editor.org/info/rfc5226>.
11.2. Informative References [RFC6952] Jethanandani, M., Patel, K., and L. Zheng, "Analysis of
BGP, LDP, PCEP, and MSDP Issues According to the Keying
and Authentication for Routing Protocols (KARP) Design
Guide", RFC 6952, May 2013,
<http://www.rfc-editor.org/info/rfc6952>.
[IANA.AFI] Acknowledgements
IANA, "Address Family Numbers",
<http://www.iana.org/assignments/address-family-numbers/
address-family-numbers.xhtml>.
[IANA.EVPN] The authors wish to acknowledge Han Nguyen, James Uttaro, and Alvaro
IANA, "Ethernet VPN (EVPN)", Retana for their comments and contributions.
<http://www.iana.org/assignments/evpn/evpn.xhtml>.
[IANA.SAFI] Contributors
IANA, "Subsequent Address Family Identifiers (SAFI)
Parameters", <http://www.iana.org/assignments/safi-
namespace/safi-namespace.xhtml#safi-namespace-2>.
[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private The following individuals contributed to the development of this
Networks (VPNs)", RFC 4364, February 2006. document:
[RFC6952] Jethanandani, M., Patel, K., and L. Zheng, "Analysis of o Yakov Rekhter
BGP, LDP, PCEP, and MSDP Issues According to the Keying
and Authentication for Routing Protocols (KARP) Design o Xiaohu Xu
Guide", RFC 6952, May 2013.
Authors' Addresses Authors' Addresses
Huajin Jeng Huajin Jeng
AT&T AT&T
Email: hj2387@att.com EMail: hj2387@att.com
Luay Jalil Luay Jalil
Verizon Verizon
Email: luay.jalil@verizon.com EMail: luay.jalil@verizon.com
Ron Bonica Ron Bonica
Juniper Networks Juniper Networks
2251 Corporate Park Drive 2251 Corporate Park Drive
Herndon, Virginia 20170 Herndon, Virginia 20170
USA United States
Email: rbonica@juniper.net EMail: rbonica@juniper.net
Keyur Patel Keyur Patel
Cisco Systems Cisco Systems
170 W. Tasman Drive 170 W. Tasman Drive
San Jose, California 95134 San Jose, California 95134
USA United States
EMail: keyupate@cisco.com
Email: keyupate@cisco.com
Lucy Yong Lucy Yong
Huawei Technologies Huawei Technologies
Austin, Texas Austin, Texas
USA United States
Email: lucy.yong@huawei.com EMail: lucy.yong@huawei.com
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