BESS Workgroup A. Sajassi (Editor)
INTERNET-DRAFT S. Salam
Intended Status: Standard Track Cisco
N. Del Regno
Verizon
J. Rabadan
Nokia
Expires: July 31, 2019 January 31, 2019
(PBB-)EVPN Seamless Integration with (PBB-)VPLS
draft-ietf-bess-evpn-vpls-seamless-integ-07
Abstract
This document specifies mechanisms for backward compatibility of
Ethernet VPN (EVPN) and Provider Backbone Bridge Ethernet VPN (PBB-
EVPN) solutions with Virtual Private LAN Service (VPLS) and Provider
Backbone Bridge VPLS (PBB-VPLS) solutions. It also provides
mechanisms for seamless integration of these two technologies in the
same MPLS/IP network on a per-VPN-instance basis. Implementation of
this document enables service providers to introduce EVPN/PBB-EVPN
PEs in their brown-field deployments of VPLS/PBB-VPLS networks. This
document specifies control-plane and forwarding behavior needed for
auto-discovery of a VPN instance, multicast and unicast operation, as
well as MAC-mobility operation in order to enable seamless
integration between EVPN and VPLS PEs as well as between PBB-VPLS and
PBB-EVPN PEs.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as
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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."
The list of current Internet-Drafts can be accessed at
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http://www.ietf.org/1id-abstracts.html
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html
Copyright and License Notice
Copyright (c) 2018 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
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Specification of Requirements . . . . . . . . . . . . . . 5
1.2. Terms and Abbreviations . . . . . . . . . . . . . . . . . 5
2. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 7
3 VPLS Integration with EVPN . . . . . . . . . . . . . . . . . . . 8
3.1 Capability Discovery . . . . . . . . . . . . . . . . . . . . 8
3.2 Forwarding Setup and Unicast Operation . . . . . . . . . . . 8
3.3 MAC Mobility . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Multicast Operation . . . . . . . . . . . . . . . . . . . . 10
3.4.1 Ingress Replication . . . . . . . . . . . . . . . . . . 10
3.4.2 P2MP Tunnel . . . . . . . . . . . . . . . . . . . . . . 11
4 PBB-VPLS Integration with PBB-EVPN . . . . . . . . . . . . . . . 11
4.1 Capability Discovery . . . . . . . . . . . . . . . . . . . . 11
4.2 Forwarding Setup and Unicast Operation . . . . . . . . . . . 11
4.3 MAC Mobility . . . . . . . . . . . . . . . . . . . . . . . . 13
4.4 Multicast Operation . . . . . . . . . . . . . . . . . . . . 13
4.4.1 Ingress Replication . . . . . . . . . . . . . . . . . . 13
4.4.2 P2MP Tunnel - Inclusive Tree . . . . . . . . . . . . . . 14
5 Security Considerations . . . . . . . . . . . . . . . . . . . . 14
6 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 14
7 References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
7.1 Normative References . . . . . . . . . . . . . . . . . . . 14
7.2 Informative References . . . . . . . . . . . . . . . . . . 15
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Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
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1 Introduction
Virtual Private LAN Service (VPLS) and Provider Backbone Bridging
VPLS (PBB-VPLS) are widely-deployed Layer-2 VPN (L2VPN) technologies.
Many service providers who are looking at adopting Ethernet VPN
(EVPN) and Provider Backbone Bridging EVPN (PBB-EVPN) want to
preserve their investment in the VPLS and PBB-VPLS networks. Hence,
they require mechanisms by which EVPN and PBB-EVPN technologies can
be introduced into their brown-field VPLS and PBB-VPLS networks
without requiring any upgrades (software or hardware) to these
networks. This document specifies procedures for the seamless
integration of the two technologies in the same MPLS/IP network.
Throughout this document, we use the term (PBB-)EVPN to correspond to
both EVPN and PBB-EVPN and we use the term (PBB-)VPLS to correspond
to both VPLS and PBB-VPLS. This document specifies control-plane and
forwarding behavior needed for auto-discovery of a VPN instance,
multicast and unicast operations, as well as MAC-mobility operation
in order to enable seamless integration between (PBB-)EVPN Provider
Edge(PE) devices and (PBB-)VPLS PEs.
VPLS PE
+---+
|PE1|
+---+
/
EVPN/VPLS PE +---------------+ EVPN/VPLS PE
+---+ | | +---+
|PE4|----| MPLS/IP |---|PE5|
+---+ | Core | +---+
| |
+---------------+
/ \
+---+ +---+
|PE2| |PE3|
+---+ +---+
VPLS PE VPLS PE
Figure 1: Seamless Integration of (PBB-)EVPN & (PBB-)VPLS
Section 2 provides the details of the requirements. Section 3
specifies procedures for the seamless integration of VPLS and EVPN
networks. And section 4 specifies procedures for the seamless
integration of PBB-VPLS and PBB-EVPN networks.
It should be noted that the scenarios for PBB-VPLS integration with
EVPN and VPLS integration with PBB-EVPN are not covered in this
document because there haven't been any requirements from service
providers for these scenarios. The reason for that is that
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deployments which employ PBB-VPLS typically require PBB encapsulation
for various reasons. Hence, it is expected that for those deployments
the evolution path would be from PBB-VPLS towards PBB-EVPN.
Furthermore, the evolution path from VPLS is expected to be towards
EVPN.
The seamless integration solution described in this document has the
following attributes:
- When ingress replication is used for multi-destination traffic
delivery, the solution reduces the scope of [MMRP] (which is a soft-
state protocol) to only that of existing VPLS PEs, and uses the more
robust BGP-based mechanism for multicast pruning among new EVPN PEs.
- It is completely backward compatible.
- New PEs can leverage the extensive multi-homing mechanisms and
provisioning simplifications of (PBB-)EVPN:
a. Auto-sensing of MHN / MHD
b. Auto-discovery of redundancy group
c. Auto-provisioning of Designated Forwarder election and
VLAN carving
1.1. Specification of Requirements
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
1.2. Terms and Abbreviations
Broadcast Domain: In a bridged network, the broadcast domain
corresponds to a Virtual LAN (VLAN), where a VLAN is typically
represented by a single VLAN ID (VID) but can be represented by
several VIDs where Shared VLAN Learning (SVL) is used per
[IEEE.802.1ah].
Bridge Table: An instantiation of a broadcast domain on a MAC-VRF
RIB: Routing Information Base - An instantiation of a routing table
on a MAC-VRF
FIB: Forwarding Information Base - An instantiation of a forwarding
table on a MAC-VRF
CE: A Customer Edge device, e.g., a host, router, or switch.
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MAC-VRF: A Virtual Routing and Forwarding table for Media Access
Control (MAC) addresses on an EVPN PE.
MAC address: Media Access Control address
C-MAC address: Customer MAC address - e.g., host or CE's MAC address
B-MAC address: Backbone MAC address - e.g., PE's MAC address
Ethernet segment (ES): Refers to the set of Ethernet links that
connects a customer site (device or network) to one or more PEs.
Ethernet Tag: An Ethernet Tag identifies a particular broadcast
domain, e.g., a VLAN. An EVPN instance consists of one or more
broadcast domains
FEC: Forwarding Equivalence Class
LSP: Label Switched Path
MHD: Multi-Homed Device
MHN: Multi-Homed Network
P2MP: Point to Multipoint - a P2MP LSP typically refers to a LSP for
multicast traffic
MP2P: Multipoint to Point - a MP2P LSP typically refers to a LSP for
unicast traffic as the result of downstream-assigned label
PBB: Provider Backbone Bridge
PE: Provider Edge device
VSI: Virtual Switch Instance
VPLS: Virtual Private LAN Service
Single-Active Redundancy Mode: When only a single PE, among all the
PEs attached to an Ethernet segment, is allowed to forward traffic
to/from that Ethernet segment for a given VLAN, then the Ethernet
segment is defined to be operating in Single-Active redundancy mode.
All-Active Redundancy Mode: When all PEs attached to an Ethernet
segment are allowed to forward known unicast traffic to/from that
Ethernet segment for a given VLAN, then the Ethernet segment is
defined to be operating in All-Active redundancy mode.
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(PBB-)EVPN: refers to both, PBB-EVPN and EVPN. This document uses
this abbreviation when a given description applies to both
technologies.
(PBB-)VPLS: refers to both, PBB-VPLS and VPLS. This document uses
this abbreviation when a given description applies to both
technologies.
VPLS A-D: refers to Virtual Private LAN Services with BGP-based Auto
Discovery as in [RFC6074].
PW: Pseudowire
I-SID: Ethernet Services Instance Identifier
2. Requirements
Following are the key requirements for backward compatibility between
(PBB-)EVPN and (PBB-)VPLS:
1. The solution must allow for staged migration towards (PBB-)EVPN on
a site-by-site basis per VPN instance - e.g., new EVPN sites to be
provisioned on (PBB-)EVPN Provider Edge devices (PEs).
2. The solution must not require any changes to existing VPLS or PBB-
VPLS PEs, not even a software upgrade.
3. The solution must allow for the co-existence of PE devices running
(PBB-)EVPN and (PBB-)VPLS for the same VPN instance and single-homed
segments.
4. The solution must support single-active redundancy of multi-homed
networks and multi-homed devices for (PBB-)EVPN PEs.
5. In case of single-active redundancy, the participant VPN instances
may span across both (PBB-)EVPN PEs and (PBB-)VPLS PEs as long as the
MHD or MHN is connected to (PBB-)EVPN PEs.
6. The support of All-Active redundancy mode across both (PBB-)EVPN
PEs and (PBB-)VPLS PEs is outside the scope of this document. All-
Active redundancy is not applicable to VPLS and PBB-VPLS. Therefore,
when EVPN (or PBB-EVPN) PEs need to operate seamlessly with VPLS (or
PBB-VPLS) PEs, then they MUST use a redundancy mode that is
applicable to VPLS (or PBB-VPLS). This redundancy mode is Single-
Active.
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These requirements collectively allow for the seamless insertion of
the (PBB-)EVPN technology into brown-field (PBB-)VPLS deployments.
3 VPLS Integration with EVPN
In order to support seamless integration with VPLS PEs, this document
requires that VPLS PEs support VPLS A-D per [RFC6074] and EVPN PEs
support both BGP EVPN routes per [RFC7432] and VPLS A-D per
[RFC6074]. All the logic for seamless integration shall reside on the
EVPN PEs. If a VPLS instance is setup without the use of VPLS A-D, it
is still possible (but cumbersome) for EVPN PEs to integrate into
that VPLS instance by manually configuring Pseudowires (PWs) to all
the VPLS PEs in that instance (i.e., the integration is no longer
seamless).
3.1 Capability Discovery
The EVPN PEs MUST advertise both the BGP VPLS Auto-Discovery (A-D)
route as well as the BGP EVPN Inclusive Multicast Ethernet Tag (IMET)
route for a given VPN instance. The VPLS PEs only advertise the BGP
VPLS A-D route, per the procedures specified in [RFC4761], [RFC4762]
and [RFC6074]. The operator may decide to use the same Route Target
(RT) to identify a VPN on both EVPN and VPLS networks. In this case,
when a VPLS PE receives the EVPN IMET route, it MUST ignore it on the
basis that it belongs to an unknown SAFI. However, the operator may
choose to use two RTs - one to identify the VPN on VPLS network and
another for EVPN network and employ RT-constrained [RFC4684] in order
to prevent BGP EVPN routes from reaching the VPLS PEs.
When an EVPN PE receives both a VPLS A-D route as well as an EVPN
IMET route from a given remote PE for the same VPN instance, it MUST
give preference to the EVPN route for the purpose of discovery. This
ensures that, at the end of the route exchanges, all EVPN capable PEs
discover other EVPN capable PEs in addition to the VPLS-only PEs for
that VPN instance. Furthermore, all the VPLS-only PEs will discover
the EVPN PEs as if they were standard VPLS PEs. In other words, when
the discovery phase is complete, the EVPN PEs will have discovered
all the PEs in the VPN instance along with their associated
capability (EVPN or VPLS-only), whereas the VPLS PEs will have
discovered all the PEs in the VPN instance as if they were all VPLS-
only PEs.
3.2 Forwarding Setup and Unicast Operation
The procedures for forwarding state setup and unicast operation on
the VPLS PE are per [RFC8077], [RFC4761], [RFC4762].
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The procedures for forwarding state setup and unicast operation on
the EVPN PE are as follows:
- The EVPN PE MUST establish a PW to each remote PE from which it has
received only a VPLS A-D route for the corresponding VPN instance,
and MUST set up the label stack corresponding to the PW FEC. For
seamless integration between EVPN and VPLS PEs, the PW that is setup
between a pair of VPLS and EVPN PEs is between the VSI of the VPLS PE
and the MAC-VRF of the EVPN PE.
- The EVPN PE MUST set up the label stack corresponding to the MP2P
VPN unicast FEC to any remote PE that has advertised EVPN IMET route.
- If an EVPN PE receives a VPLS A-D route from a given PE, it sets up
a PW to that PE. If it then receives an EVPN IMET route from the same
PE, then the EVPN PE MUST bring that PW operationally down.
- If an EVPN PE receives an EVPN IMET route followed by a VPLS A-D
route from the same PE, then the EVPN PE will setup the PW but MUST
keep it operationally down.
- In case VPLS A-D is not used in some VPLS PEs, the EVPN PEs need to
be provisioned manually with PWs to those remote VPLS PEs for each
VPN instance. In that case, if an EVPN PE receives an EVPN IMET route
from a PE to which a PW exists, the EVPN PE MUST bring the PW
operationally down.
When the EVPN PE receives traffic over the VPLS PWs, it learns the
associated C-MAC addresses in the data-plane. The C-MAC addresses
learned over these PWs MUST be injected into the bridge table of the
associated MAC-VRF on that EVPN PE. The learned C-MAC addresses MAY
also be injected into the RIB/FIB tables of the associated MAC-VRF on
that EVPN PE. For seamless integration between EVPN and VPLS PEs,
since these PWs belong to the same split-horizon group ([RFC4761] and
[RFC4762]) as the MP2P EVPN service tunnels, then the C-MAC addresses
learned and associated to the PWs MUST NOT be advertised in the
control plane to any remote EVPN PEs. This is because every EVPN PE
can send and receive traffic directly to/from every VPLS PE belonging
to the same VPN instance and thus every EVPN PE can learn the C-MAC
addresses over the corresponding PWs directly.
The C-MAC addresses learned over local Attachment Circuits (ACs) by
an EVPN PE are learned in data-plane. For EVPN PEs, these C-MAC
addresses MUST be injected into the corresponding MAC-VRF and
advertised in the control-plane using BGP EVPN routes. Furthermore,
the C-MAC addresses learned in the control plane via the BGP EVPN
routes sent by remote EVPN PEs, are injected into the corresponding
MAC-VRF table.
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In case of a link failure in a single-active Ethernet Segment, the
EVPN PEs MUST perform both of the following tasks:
a) send a BGP mass-withdraw to the EVPN peers
b) follow existing VPLS MAC Flush procedures with the VPLS peers.
3.3 MAC Mobility
In EVPN, host addresses (C-MAC addresses) can move around among EVPN
PEs or even between EVPN and VPLS PEs.
When a C-MAC address moves from an EVPN PE to a VPLS PE, then as soon
as Broadcast/Unknown-unicast/Multicast (BUM) traffic is initiated
from that MAC address, it is flooded to all other PEs (both VPLS and
EVPN PEs) and the receiving PEs update their MAC tables (VSI or MAC-
VRF). The EVPN PEs do not advertise the C-MAC addresses learned over
the PW to each other because every EVPN PE learns them directly over
its associated PW to that VPLS PE. If only known-unicast traffic is
initiated from the moved C-MAC address toward a known C-MAC, then
this can result in black-holing of traffic destined to the C-MAC that
has moved until there is a BUM traffic originated with the moved C-
MAC address as the source MAC address (e.g., as a result of MAC age-
out timer expires). Such black-holing happens for traffic destined to
the moved C-MAC from both EVPN and VPLS PEs. It should be noted that
such black-holing behavior is typical for VPLS PEs.
When a C-MAC address moves from a VPLS PE to an EVPN PE, then as soon
as any traffic is initiated from that C-MAC address, the C-MAC is
learned and advertised in BGP to other EVPN PEs and MAC mobility
procedure is exercised among EVPN PEs. For BUM traffic, both EVPN and
VPLS PEs learn the new location of the moved C-MAC address; however,
if there is only known-unicast traffic, then only EVPN PEs learn the
new location of the C-MAC that has moved but not VPLS PEs. This can
result in black-holing of traffic sent from VPLS PEs destined to the
C-MAC that has moved until there is a BUM traffic originated with the
moved C-MAC address as the source MAC address (e.g., as a result of
MAC age-out timer expires). Such black-holing happens for traffic
destined to the moved C-MAC for only VPLS PEs but not for EVPN PEs.
It should be noted that such black-holing behavior is typical for
VPLS PEs.
3.4 Multicast Operation
3.4.1 Ingress Replication
The procedures for multicast operation on the VPLS PE, using ingress
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replication, are per [RFC4761], [RFC4762], and [RFC7080].
The procedures for multicast operation on the EVPN PE, for ingress
replication, are as follows:
- The EVPN PE builds a replication sub-list to all the remote EVPN
PEs per EVPN instance as the result of the exchange of the EVPN IMET
routes per [RFC7432]. This will be referred to as sub-list A. It
comprises MP2P service tunnels (for ingress replication) used for
delivering EVPN BUM traffic [RFC7432].
- The EVPN PE builds a replication sub-list per VPLS instance to all
the remote VPLS PEs. This will be referred to as sub-list B. It
comprises PWs from the EVPN PE in question to all the remote VPLS PEs
in the same VPLS instance.
The replication list, maintained per VPN instance, on a given EVPN PE
will be the union of sub-list A and sub-list B. The EVPN PE MUST
enable split-horizon over all the entries in the replication list,
across both PWs and MP2P service tunnels.
3.4.2 P2MP Tunnel
The procedures for multicast operation on the EVPN PEs using P2MP
tunnels are outside of the scope of this document.
4 PBB-VPLS Integration with PBB-EVPN
In order to support seamless integration between PBB-VPLS and PBB-
EVPN PEs, this document requires that PBB-VPLS PEs support VPLS A-D
per [RFC6074] and PBB-EVPN PEs support both BGP EVPN routes per
[RFC7432] and VPLS A-D per [RFC6074]. All the logic for this seamless
integration shall reside on the PBB-EVPN PEs.
4.1 Capability Discovery
The procedures for capability discovery are per Section 3.1 above.
4.2 Forwarding Setup and Unicast Operation
The procedures for forwarding state setup and unicast operation on
the PBB-VPLS PE are per [RFC8077] and [RFC7080].
The procedures for forwarding state setup and unicast operation on
the PBB-EVPN PE are as follows:
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- The PBB-EVPN PE MUST establish a PW to each remote PBB-VPLS PE from
which it has received only a VPLS A-D route for the corresponding VPN
instance, and MUST set up the label stack corresponding to the PW
FEC. For seamless integration between PBB-EVPN and PBB-VPLS PEs, the
PW that is setup between a pair of PBB-VPLS and PBB-EVPN PEs, is
between B-components of PBB-EVPN PE and PBB-VPLS PE per section 4 of
[RFC7041].
- The PBB-EVPN PE MUST set up the label stack corresponding to the
MP2P VPN unicast FEC to any remote PBB-EVPN PE that has advertised
EVPN IMET route.
- If a PBB-EVPN PE receives a VPLS A-D route from a given PE, it sets
up a PW to that PE. If it then receives an EVPN IMET route from the
same PE, then the PBB-EVPN PE MUST bring that PW operationally down.
- If a PBB-EVPN PE receives an EVPN IMET route followed by a VPLS A-D
route from the same PE, then the PBB-EVPN PE will setup the PW but
MUST keep it operationally down.
- In case VPLS A-D is not used in some PBB-VPLS PEs, the PBB-EVPN PEs
need to be provisioned manually with PWs to those remote PBB-VPLS PEs
for each VPN instance. In that case, if a PBB-EVPN PE receives an
EVPN IMET route from a PE to which a PW exists, the PBB-EVPN PE MUST
bring the PW operationally down.
- When the PBB-EVPN PE receives traffic over the PBB-VPLS PWs, it
learns the associated B-MAC addresses in the data-plane. The B-MAC
addresses learned over these PWs MUST be injected into the bridge
table of the associated MAC-VRF on that PBB-EVPN PE. The learned B-
MAC addresses MAY also be injected into the RIB/FIB tables of the
associated the MAC-VRF on that BPP-EVPN PE. For seamless integration
between PBB-EVPN and PBB-VPLS PEs, since these PWs belongs to the
same split-horizon group as the MP2P EVPN service tunnels, then the
B-MAC addresses learned and associated to the PWs MUST NOT be
advertised in the control plane to any remote PBB-EVPN PEs. This is
because every PBB-EVPN PE can send and receive traffic directly
to/from every PBB-VPLS PE belonging to the same VPN instance.
- The C-MAC addresses learned over local Attachment Circuits (ACs) by
an PBB-EVPN PE are learned in data-plane. For PBB-EVPN PEs, these C-
MAC addresses are learned in I-component of PBB-EVPN PEs and they are
not advertised in the control-plane per [RFC7623].
- The B-MAC addresses learned in the control plane via the BGP EVPN
routes sent by remote PBB-EVPN PEs, are injected into the
corresponding MAC-VRF table.
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In case of a link failure in a single-active Ethernet Segment, the
PBB-EVPN PEs MUST perform both of the following tasks:
a) send a BGP B-MAC withdraw message to the PBB-EVPN peers OR MAC
advertisement with MAC Mobility extended community
b) follow existing VPLS MAC Flush procedures with the PBB-VPLS peers
4.3 MAC Mobility
In PBB-EVPN, a given B-MAC address can be learned either over the BGP
control-plane from a remote PBB-EVPN PE, or in the data-plane over a
PW from a remote PBB-VPLS PE. There is no mobility associated with B-
MAC addresses in this context. Hence, when the same B-MAC address
shows up behind both a remote PBB-VPLS PE as well as a PBB-EVPN PE,
the local PE can deduce that it is an anomaly and SHOULD notify the
operator.
4.4 Multicast Operation
4.4.1 Ingress Replication
The procedures for multicast operation on the PBB-VPLS PE, using
ingress replication, are per [RFC7041] and [RFC7080].
The procedures for multicast operation on the PBB-EVPN PE, for
ingress replication, are as follows:
- The PBB-EVPN PE builds a replication sub-list per I-SID to all the
remote PBB-EVPN PEs in a given VPN instance as a result of the
exchange of the EVPN IMET routes, as described in [RFC7623]. This
will be referred to as sub-list A. It comprises MP2P service tunnels
used for delivering PBB-EVPN BUM traffic.
- The PBB-EVPN PE builds a replication sub-list per VPN instance to
all the remote PBB-VPLS PEs. This will be referred to as sub-list B.
It comprises PWs from the PBB-EVPN PE in question to all the remote
PBB-VPLS PEs in the same VPN instance.
- The PBB-EVPN PE may further prune sub-list B, on a per I-SID basis,
by running [MMRP] over the PBB-VPLS network. This will be referred to
as sub-list C. This list comprises a pruned set of the PWs in the
sub-list B.
The replication list maintained per I-SID on a given PBB-EVPN PE will
be the union of sub-list A and sub-list B if [MMRP] is not used, and
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the union of sub-list A and sub-list C if [MMRP] is used. Note that
the PE MUST enable split-horizon over all the entries in the
replication list, across both pseudowires and MP2P service tunnels.
4.4.2 P2MP Tunnel - Inclusive Tree
The procedures for multicast operation on the PBB-EVPN PEs using P2MP
tunnels are outside of the scope of this document.
5 Security Considerations
All the security considerations in [RFC4761], [RFC4762], [RFC7080],
[RFC7432], and [RFC7623] apply directly to this document because this
document leverages the control plane and the data plane procedures
described in these RFCs.
This document does not introduce any new security considerations
beyond that of the above RFCs because the advertisements and
processing of MAC addresses in BGP follow that of [RFC7432] and
processing of MAC addresses learned over PWs follow that of
[RFC4761], [RFC4762], and [RFC7080].
6 IANA Considerations
This document has no actions for IANA.
7 References
7.1 Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, DOI
10.17487/RFC2119, March <https://www.rfc-
editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8077] Martini, et al., "Pseudowire Setup and Maintenance using
the Label Distribution Protocol", RFC 8077, February 2017.
[RFC7432] Sajassi et al., "BGP MPLS Based Ethernet VPN", RFC 7432,
February, 2015.
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[RFC7623] Sajassi et al., "Provider Backbone Bridging Combined with
Ethernet VPN (PBB-EVPN)", RFC 7623, September, 2015.
[RFC4761] Kompella, K., Ed., and Y. Rekhter, Ed., "Virtual Private
LAN Service (VPLS) Using BGP for Auto-Discovery and
Signaling", RFC 4761, January 2007, <http://www.rfc-
editor.org/info/rfc4761>.
[RFC4762] Lasserre, M., Ed., and V. Kompella, Ed., "Virtual Private
LAN Service (VPLS) Using Label Distribution Protocol (LDP)
Signaling", RFC 4762, January 2007, <http://www.rfc-
editor.org/info/rfc4762>.
[RFC7041] Balus et al., "Extensions to VPLS PE model for Provider
Backbone Bridging", RFC 7041, November 2013.
[RFC6074] Rosen et al., "Provisioning, Auto-Discovery, and Signaling
in Layer 2 Virtual Private Networks (L2VPNs)", RFC 6074,
January 2011.
7.2 Informative References
[MMRP] Clause 10 of "IEEE Standard for Local and metropolitan area
networks - Media Access Control (MAC) Bridges and Virtual Bridged
Local Area Networks", IEEE Std 802.1Q, 2013.
[RFC7080] Sajassi et al., "VPLS Interoperability with Provider
Backbone Bridges", RFC 7080, December, 2013.
[IEEE.802.1ah] IEEE, "IEEE Standard for Local and metropolitan area
networks - Media Access Control (MAC) Bridges and Virtual Bridged
Local Area Networks", Clauses 25 and 26, IEEE Std 802.1Q, DOI
10.1109/IEEESTD.2011.6009146.
[RFC4684] Marques et al., "Constrained Route Distribution for Border
Gateway Protocol/MultiProtocol Label Switching (BGP/MPLS) Internet
Protocol (IP) Virtual Private Networks (VPNs)", RFC 4684, November,
2006.
Authors' Addresses
Ali Sajassi
Cisco
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Email: sajassi@cisco.com
Samer Salam
Cisco
Email: ssalam@cisco.com
Nick Del Regno
Verizon
Email: nick.delregno@verizon.com
Jorge Rabadan
Nokia
Email: jorge.rabadan@nokia.com
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