wdiff rfc7209.original rfc7209.txt

Internet Working Group Engineering Task Force (IETF) A. Sajassi
INTERNET-DRAFT
Request for Comments: 7209 Cisco
Category: Informational R. Aggarwal
ISSN: 2070-1721 Arktan
J. Uttaro Arktan
AT&T
N. Bitar
Verizon
W. Henderickx Verizon
Alcatel-Lucent
Aldrin
A. Isaac
Bloomberg

Expires: August 4, 2014 February 4,
May 2014

Requirements for Ethernet VPN (EVPN)
draft-ietf-l2vpn-evpn-req-07.txt

Status

Abstract

The widespread adoption of this Memo

This Internet-Draft Ethernet L2VPN services and the advent of
new applications for the technology (e.g., data center interconnect)
have culminated in a new set of requirements that are not readily
addressable by the current Virtual Private LAN Service (VPLS)
solution. In particular, multihoming with all-active forwarding is submitted
not supported, and there's no existing solution to IETF leverage
Multipoint-to-Multipoint (MP2MP) Label Switched Paths (LSPs) for
optimizing the delivery of multi-destination frames. Furthermore,
the provisioning of VPLS, even in full conformance with the
provisions context of BCP 78 and BCP 79.

Internet-Drafts are working documents BGP-based auto-
discovery, requires network operators to specify various network
parameters on top of the access configuration. This document
specifies the requirements for an Ethernet VPN (EVPN) solution, which
addresses the above issues.

Status of This Memo

This document is not an Internet Standards Track specification; it is
published for informational purposes.

This document is a product of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as
Internet-Drafts.

Internet-Drafts are draft documents valid for a maximum
(IETF). It represents the consensus of six months the IETF community. It has
received public review and may be updated, replaced, or obsoleted has been approved for publication by other the
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approved by the IESG are a candidate for any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."

The list level of Internet
Standard; see Section 2 of RFC 5741.

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http://www.rfc-editor.org/info/rfc7209.

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Abstract

The widespread adoption of Ethernet L2VPN services and the advent of
new applications for the technology (e.g., data center interconnect)
have culminated in a new set of requirements that are not readily
addressable by the current Virtual Private LAN Service (VPLS)
solution. In particular, multi-homing with all-active forwarding is
not supported and there's no existing solution to leverage
Multipoint-to-Multipoint (MP2MP) LSPs for optimizing the delivery of
multi-destination frames. Furthermore, the provisioning of VPLS, even
in the context of BGP-based auto-discovery, requires network
operators to specify various network parameters on top of the access
configuration. This document specifies the requirements for an
Ethernet VPN (EVPN) solution which addresses the above issues.

Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 ....................................................3
2. Specification of requirements . . . . . . . . . . . . . . . . . 5 Requirements ...................................4
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 5 .....................................................4
4. Redundancy Requirements . . . . . . . . . . . . . . . . . . . . 6 .........................................5
4.1. Flow-based Flow-Based Load Balancing . . . . . . . . . . . . . . . . 6 ..................................5
4.2. Flow-based Multi-pathing . . . . . . . . . . . . . . . . . 7 Flow-Based Multipathing ....................................6
4.3. Geo-redundant PE Nodes . . . . . . . . . . . . . . . . . . 7 .....................................7
4.4. Optimal Traffic Forwarding . . . . . . . . . . . . . . . . 8 .................................7
4.5. Support for Flexible Redundancy Grouping Support . . . . . . . . . . . 8 ...................8
4.6. Multi-homed Multihomed Network . . . . . . . . . . . . . . . . . . . 9 .........................................8
5. Multicast Optimization Requirements . . . . . . . . . . . . . . 9 .............................9
6. Ease of Provisioning Requirements . . . . . . . . . . . . . . . 10 ...............................9
7. New Service Interface Requirements . . . . . . . . . . . . . . 10 .............................10
8. Fast Convergence . . . . . . . . . . . . . . . . . . . . . . . 12 ...............................................12
9. Flood Suppression . . . . . . . . . . . . . . . . . . . . . . . 13 ..............................................12
10. Supporting Flexible VPN Topologies and Policies . . . . . . . 13 ...............12
11. Security Considerations . . . . . . . . . . . . . . . . . . . 13 .......................................13
12. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 14
13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
14. Normative References . . . . . . . . . . . . . . . . . . . . . 14
14. ..........................................13
13. Informative References . . . . . . . . . . . . . . . . . . . . 15
15. Author's Address . . . . . . . . . . . . . . . . . . . . . . . 15 ........................................14
14. Contributors ..................................................15

1. Introduction

VIrtual

Virtual Private LAN Service (VPLS), as defined in
[RFC4664][RFC4761][RFC4762], [RFC4664],
[RFC4761], and [RFC4762], is a proven and widely deployed technology.
However, the existing solution has a number of limitations when it
comes to redundancy, multicast optimization optimization, and provisioning
simplicity. Furthermore, new applications are driving several new
requirements for other L2VPN services such as Ethernet- Ethernet Tree (E-Tree), (E-Tree)
and Virtual Private Wire Service (VPWS).

In the area of multi-homing multihoming, current VPLS can only support multi-
homing multihoming
with active/standby resiliency model, the single-active redundancy mode (defined in Section 3), for example
example, as described in [VPLS-BGP-MH]. Flexible multi-homing multihoming with
all-active Attachment
Circuits (ACs) redundancy mode (defined in Section 3) cannot be supported
by the current VPLS solution.

In the area of multicast optimization, [VPLS-MCAST] [RFC7117] describes how
multicast LSPs can be used in conjunction with VPLS. However, this
solution is limited to Point-to-Multipoint (P2MP) LSPs, as there's no
defined solution for leveraging Multipoint-to-Multipoint (MP2MP) LSPs
with VPLS.

In the area of provisioning simplicity, current VPLS does offer a
mechanism for single-sided provisioning by relying on BGP-based
service auto-discovery [RFC4761][RFC6074]. [RFC4761] [RFC6074]. This, however, still
requires the operator to configure a number of network-side
parameters on top of the access-side Ethernet configuration.

In the area of data center data-center interconnect, applications are driving the
need for new service interface types which that are a hybrid combination of
VLAN Bundling bundling and VLAN-based service interfaces. These are referred
to as "VLAN-aware Bundling" bundling" service interfaces.

Virtualization applications are also fueling an increase in the
volume of MAC (Media Access Control) addresses that are to be handled
by the network, which network; this gives rise to the requirement for having the
network re-convergence reconvergence upon failure be independent of the number of
MAC addresses learned by the PE. Provider Edge (PE).

There are requirements for minimizing the amount of flooding of
multi-destination frames and localizing the flooding to the confines
of a given site.

There are also requirements for supporting flexible VPN topologies
and policies beyond those currently covered by (H-)VPLS. VPLS and Hierarchical
VPLS (H-VPLS).

The focus of this document is on defining the requirements for a new
solution, namely namely, Ethernet VPN (EVPN), which addresses the above
issues.

Section 4 discusses the redundancy requirements. Section 5 describes
the multicast optimization requirements. Section 6 articulates the
ease of provisioning requirements. Section 7 focuses on the new
service interface requirements. Section 8 highlights the fast
convergence requirements. Section 9 describes the flood suppression
requirement, and finally section Section 10 discusses the requirements for
supporting flexible VPN topologies and policies.

2. Specification of requirements Requirements

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 [RFC2119].

This document is not a protocol specification and the key words in
this document are used for clarity and emphasis of requirements
language.

3. Terminology

AS: Autonomous System

CE: Customer Edge

E-Tree: Ethernet tree Tree

MAC address: Media Access Control address - referred to as MAC

LSP: Label Switched Path

PE: Provider Edge

MP2MP: Multipoint to Multipoint

VPLS: Virtual Private LAN Service

Single-Active Redundancy Mode: When a device or a network is multi-
homed
multihomed to a group of two or more PEs and when only a single PE in
such a redundancy group can forward traffic to/from the multi-homed multihomed
device or network for a given VLAN, then such multi-homing multihoming is referred to
as "Single-Active".

All-Active Redundancy Mode: When a device is multi-homed multihomed to a group of
two or more PEs and when all PEs in such redundancy group can forward
traffic to/from the multi-homed multihomed device or network for a given VLAN, then
such multi-homing multihoming is referred to as "All-Active".

4. Redundancy Requirements

4.1. Flow-based Flow-Based Load Balancing

A common mechanism for multi-homing multihoming a CE node to a set of PE nodes
involves leveraging multi-chassis Ethernet link aggregation groups
(LAGs) based on [802.1AX]. [PWE3-ICCP] describes one such scheme.
In Ethernet link aggregation, the load-balancing algorithms by which
a CE distributes traffic over the Attachment Circuits connecting to
the PEs are quite flexible. The only requirement is for the
algorithm to ensure in-order frame delivery for a given traffic flow.
In typical implementations, these algorithms involve selecting an
outbound link within the bundle based on a hash function that typically
identifies a flow based on one or more of the following fields:

i. Layer 2: Source MAC Address, Destination MAC Address, VLAN
ii. Layer 3: Source IP Address, Destination IP Address
iii. Layer 4: UDP or TCP Source Port, Destination Port

A key point to note here is that [802.1AX] does not define a standard
load-balancing algorithm for Ethernet bundles, and and, as such such,
different implementations behave differently. As a matter of fact, a
bundle operates correctly even in the presence of asymmetric load-balancing load
balancing over the links. This being the case, the first requirement
for all-
active multi-homing all-active multihoming is the ability to accommodate flexible
flow-based
load-balancing load balancing from the CE node based on L2, L3 L3, and/or L4
header fields.

(R1a) A solution MUST be capable of supporting flexible flow-based
load balancing from the CE as described above.

(R1b) A solution MUST also be able to support flow-based load- load
balancing of traffic destined to the CE, even when the CE is
connected to more than one PE. Thus Thus, the solution MUST be able
to exercise multiple links connected to the CE, irrespective of
the number of PEs that the CE is connected to.

It should be noted that when a CE is multi-homed multihomed to several PEs, there
could be multiple ECMP Equal-Cost Multipath (ECMP) paths from each remote
PE to each multi-
homed multihoming PE. Furthermore, for an all-active multi-homed multihomed
CE, a remote PE can choose any of the multi-homed multihoming PEs for sending
traffic destined to the
multi-homed multihomed CE. Therefore, when a solution
supports all-active multi-
homing, multihoming, it MUST exercise as many of these
paths as possible for traffic destined to a multi-homed multihomed CE.

(R1c) A solution SHOULD support flow-based load balancing among PEs
that are members of a redundancy group spanning multiple
Autonomous Systems.

4.2. Flow-based Multi-pathing Flow-Based Multipathing

Any solution that meets the all-active redundancy mode (e.g., flow-
based load balancing) described in section Section 4.1, also needs to
exercise multiple paths between a given pair of PEs. For instance,
if there are two or more LSPs between a remote PE and a pair of PEs
in an all-active redundancy group, then the solution needs to be
capable of load balancing traffic among those LSPs on a per L2-flow per-flow
basis for traffic destined to the PEs in the redundancy group.
Furthermore, if there are two or more ECMP paths between a remote PE
and one of the
PE PEs in the redundancy group, then the solution needs
to leverage all the equal cost equal-cost LSPs. For the latter, the solution
can also leverage the load balancing load-balancing capabilities based on entropy
labels [RFC6790].

(R2a) A solution MUST be able to exercise all LSPs between a remote
PE and all the PEs in the redundancy group with all-active multi-
homing.
multihoming.

(R2b) A solution MUST be able to exercise all ECMP paths between a
remote PE and any of the PEs in the redundancy group with all-active
multi-homing. all-
active multihoming.

For example example, consider a scenario in which CE1 is multi-homed multihomed to PE1
and PE2, and CE2 is multi-homed multihomed to PE3 and PE4 running in all-active
redundancy mode. Furthermore, consider that there exist three ECMP
paths between any of the CE1's and CE2's multi-homed multihomed PEs. Traffic
from CE1 to CE2 can be forwarded on twelve different paths over the
MPLS/IP core as follow: follows: CE1 load balances traffic to both PE1 and
PE2. Each of the PE1 and PE2 have three ECMP paths to PE3 and PE4 for
the a
total of twelve paths. Finally, when traffic arrives at PE3 and PE4,
it gets forwarded to CE2 over the Ethernet channel (aka link bundle).

It is worth pointing out that flow-based multi-pathing multipathing complements
flow-based load balancing described in the previous section.

4.3. Geo-redundant PE Nodes

The PE nodes offering multi-homed multihomed connectivity to a CE or access
network may be situated in the same physical location (co-located),
or may be spread geographically (e.g., in different COs Central Offices
(COs) or POPs). Points of Presence (POPs)). The latter is needed when
offering a geo-redundant solution that ensures business continuity
for critical applications in the case of power outages, natural
disasters, etc. An all-active multi-homing multihoming mechanism needs to support
both co-located as well as geo-redundant PE placement. The latter
scenario often means that requiring a dedicated link between the PEs,
for the operation of the multi-homing multihoming mechanism, is not appealing from
a cost standpoint. Furthermore, the IGP cost from remote PEs to the
pair of PEs in the dual-homed setup cannot be assumed to be the same
when those latter PEs are geo-
redundant. geo-redundant.

(R3a) A solution MUST support all-active multi-homing multihoming without the need
for a dedicated control/data link among the PEs in the multi-
homed
multihomed group.

(R3b) A solution MUST support different IGP costs from a remote PE to
each of the PEs in a multi-homed multihomed group.

(R3c) A solution MUST support multi-homing multihoming across different IGP
domains within the same Autonomous System.

(R3d) A solution SHOULD support multi-homing multihoming across multiple
Autonomous Systems.

4.4. Optimal Traffic Forwarding

In a typical network, and when considering a designated pair of PEs, it
is common to find both single-homed as well as multi-homed multihomed CEs being
connected to those PEs.

(R4):

(R4) An all-active multi-homing multihoming solution SHOULD support optimal
forwarding of unicast traffic for all the following scenarios.
By "optimal forwarding", we mean that traffic will not be
forwarded between PE devices that are members of a multi-home multihomed
group unless the destination CE is attached to one of the multi-homed
multihoming PEs.

i. single-homed CE to multi-homed multihomed CE
ii. multi-homed multihomed CE to single-homed CE
iii. multi-homed multihomed CE to multi-homed multihomed CE

This is especially important in the case of geo-redundant PEs, where
having traffic forwarded from one PE to another within the same
multi-homed
multihomed group introduces additional latency, on top of the
inefficient use of the PE node's and core nodes' switching capacity.
A multi-homed multihomed group (also known as a multi-chassis LAG) is a group of
PEs supporting a multi-homed multihomed CE.

4.5. Support for Flexible Redundancy Grouping Support

(R5) In order to support flexible redundancy grouping, the multi-
homing
multihoming mechanism SHOULD allow arbitrary grouping of PE
nodes into redundancy groups where each redundancy group
represents all multi-
homed multihomed devices/networks that share the same
group of PEs.

This is best explained with an example: consider three PE nodes - --
PE1, PE2 PE2, and PE3. The multi-homing multihoming mechanism MUST allow a given PE,
say
say, PE1, to be part of multiple redundancy groups concurrently. For
example, there can be a group (PE1, PE2), a group (PE1, PE3), and
another group (PE2, PE3) where CEs could be multi-homed multihomed to any one of
these three redundancy groups.

4.6. Multi-homed Multihomed Network

There are applications, applications that require an Ethernet network, rather than
a single device, to be multi-homed multihomed to a group of PEs. The Ethernet
network would typically run a resiliency mechanism such as Multiple
Spanning Tree Protocol [802.1Q] or Ethernet Ring Protection Switching
[G.8032]. The PEs may or may not participate in the control protocol
of the Ethernet network. For a multi-homed multihomed network running [802.1Q]
or [G.8032], these protocols require that each VLAN to be active only
on one of the multi-homed multihomed links.

(R6a) A solution MUST support multi-homed multihomed network connectivity with
active/standby
single-active redundancy mode where all VLANs are active on one
PE.

(R6b) A solution MUST also support multi-homed network multihomed networks with single-
active redundancy mode where disjoint VLAN sets are active on
disparate PEs.

(R6c) A solution SHOULD support single-active redundancy mode among
PEs that are member members of a redundancy group spanning multiple
ASes.

(R6d) A solution MAY support all-active redundancy mode for a multi-
homed
multihomed network with MAC-based load balancing (i.e. (i.e.,
different MAC addresses on a VLAN are reachable via different
PEs).

5. Multicast Optimization Requirements

There are environments where the use of MP2MP LSPs may be desirable
for optimizing multicast, broadcast broadcast, and unknown unicast traffic in
order to reduce the amount of multicast states in the core routers.
[VPLS-MCAST]
[RFC7117] precludes the use of MP2MP LSPs since current VPLS
solutions require an egress PE to perform learning when it receives
unknown unicast packets over a an LSP. This is challenging when MP2MP
LSPs are used, as MP2MP LSPs they do not have inherent mechanisms to identify
the sender. The use of MP2MP LSPs for multicast optimization becomes
tractable if the need to identify the sender for performing learning
is lifted.

(R7a) A solution MUST be able to provide a mechanism that does not
require MAC learning against MPLS LSPs when packets are
received over a MP2MP LSP.

(R7b) A solution SHOULD be able to provide procedures to use MP2MP
LSPs for optimizing delivery of multicast, broadcast broadcast, and
unknown unicast traffic.

6. Ease of Provisioning Requirements

As L2VPN technologies expand into enterprise deployments, ease of
provisioning becomes paramount. Even though current VPLS has an auto-
discovery
auto-discovery mechanism, which enables automated discovery of member
PEs belonging to a given VPN instance over the MPLS/IP core network,
further simplifications are required, as outlined below:

(R8a) The solution MUST support auto-discovery of VPN member PEs over
the MPLS/IP core network network, similar to the VPLS auto-discovery
mechanism described in [RFC4761] and [RFC6074].

(R8b) The solution SHOULD support auto-discovery of PEs belonging to
a given redundancy or multi-homed multihomed group.

(R8c) The solution SHOULD support auto-sensing of the site-id site ID for a
multi-homed
multihomed device or network, network and support auto-generation of the
redundancy group-id group ID based on the site-id. site ID.

(R8d) The solution SHOULD support automated Designated Forwarder (DF)
election among PEs participating in a redundancy (multi-homing) (multihoming)
group and to be able to divide service instances (e.g., VLANs)
among member PEs of the redundancy group.

(R8e) For deployments where VLAN identifiers are global across the
MPLS network (i.e. (i.e., the network is limited to a maximum of 4K
services), the PE devices SHOULD derive the MPLS specific MPLS-specific
attributes (e.g., VPN ID, BGP Route Target, etc.) from the VLAN
identifier. This way, it is sufficient for the network
operator to configure the VLAN identifier(s) for the access
circuit, and all the MPLS and BGP parameters required for
setting up the service over the core network would be
automatically derived without any need for explicit
configuration.

(R8f) Implementations SHOULD revert to using default values for
parameters that for which no new values are configured for. configured.

7. New Service Interface Requirements

[MEF] and [IEEE 802.1Q] [802.1Q] have the following services specified:

- Port mode: in this mode, all traffic on the port is mapped to a
single bridge domain and a single corresponding L2VPN service
instance. Customer VLAN transparency is guaranteed end-to-end. end to end.

- VLAN mode: in this mode, each VLAN on the port is mapped to a
unique bridge domain and corresponding L2VPN service instance.
This mode allows for service multiplexing over the port and
supports optional VLAN translation.

- VLAN bundling: in this mode, a group of VLANs on the port are
collectively mapped to a unique bridge domain and corresponding
L2VPN service instance. Customer MAC addresses must be unique
across all VLANs mapped to the same service instance.

For each of the above services services, a single bridge domain is assigned
per service instance on the PE supporting the associated service.
For example, in case of the port mode, a single bridge domain is
assigned for all the ports belonging to that service instance instance,
regardless of the number of VLANs coming through these ports.

It is worth noting that the term 'bridge domain' as used above refers
to a MAC forwarding table as defined in the IEEE bridge model, model and
does not denote or imply any specific implementation.

[RFC4762] defines two types of VPLS services based on "unqualified
and qualified learning" learning", which in turn maps to port mode and VLAN mode
mode, respectively.

(R9a) A solution MUST support the above three service types. types (port
mode, VLAN mode, and VLAN bundling).

For hosted data center interconnect applications, applications for data-center interconnect, network
operators require the ability to extend Ethernet VLANs over a WAN
using a single L2VPN instance while maintaining data-plane separation
between the various VLANs associated with that instance. This is
referred to as VLAN-aware 'VLAN-aware bundling service. service'.

(R9b) A solution MAY support VLAN-aware bundle bundling service.

This gives rise to two new service interface types: VLAN-aware
bundling without translation, translation and VLAN-aware bundling with
translation.

The VLAN-aware Bundling without Translation service interface for VLAN-aware bundling without translation
has the following characteristics:

- The service interface provides bundling of customer VLANs into a
single L2VPN service instance.

- The service interface guarantees customer VLAN transparency end-to- end to
end.

- The service interface maintains data-plane separation between the
customer VLANs (i.e. create (i.e., creates a dedicated bridge-domain per VLAN).

In the special case of all-to-one bundling, the service interface
must not assume any a priori knowledge of the customer VLANs. In
other words, the customer VLANs shall not be configured on the PE,
rather PE;
rather, the interface is configured just like a port-based service.

The VLAN-aware Bundling with Translation service interface for VLAN-aware bundling with translation has
the following characteristics:

- The service interface provides bundling of customer VLANs into a
single L2VPN service instance.

- The service interface maintains data-plane separation between the
customer VLANs (i.e. create (i.e., creates a dedicated bridge-domain per VLAN).

- The service interface supports customer VLAN ID translation to
handle the scenario where different VLAN Identifiers (VIDs) are
used on different interfaces to designate the same customer VLAN.

The main difference, in terms of service provider service-provider resource
allocation, between these new service types and the previously
defined three types is that the new services require several bridge
domains to be allocated (one per customer VLAN) per L2VPN service
instance as opposed to a single bridge domain per L2VPN service
instance.

8. Fast Convergence

(R10a) A solution MUST provide the ability to recover from PE-CE
attachment circuit failures as well as PE node failure for the case
cases of both multi-homed multihomed device and multi-homed multihomed network.

(R10b) The recovery mechanism(s) MUST provide convergence time that
is independent of the number of MAC addresses learned by the
PE. This is particularly important in the context of
virtualization
applications applications, which are fueling an increase in
the number of MAC addresses to be handled by the Layer 2
network.

(R10c) Furthermore, the recovery mechanism(s) SHOULD provide
convergence time that is independent of the number of service
instances associated with the attachment circuit or the PE.

9. Flood Suppression

(R11a) The solution SHOULD allow the network operator to choose
whether unknown unicast frames are to be dropped or to be
flooded. This attribute needs to be configurable on a per service instance per-
service-instance basis.

(R11b) In addition, for the case where the solution is used for data-
center interconnect, the solution SHOULD minimize the flooding
of broadcast frames outside the confines of a given site. Of
particular interest is periodic ARP Address Resolution Protocol
(ARP) traffic.

(R11c) Furthermore, the solution SHOULD eliminate any unnecessary
flooding of unicast traffic upon topology changes, especially
in the case of multi-homed a multihomed site where the PEs have a priori
knowledge of the backup paths for a given MAC address.

10. Supporting Flexible VPN Topologies and Policies

(R12a) A solution MUST be capable of supporting flexible VPN
topologies that are not constrained by the underlying
mechanisms of the solution.

One example of this is E-TREE topology E-Tree topology, where one or more sites in
the VPN are roots and the others are leaves. The roots are allowed
to send traffic to other roots and to leaves, while leaves can
communicate only with the roots. The solution MUST provide the
ability to support E-TREE E-Tree topology.

(R12b) The solution MAY provide the ability to apply policies at the
granularity of the MAC address granularity to control which PEs in the VPN
learn which MAC address and how a specific MAC address is
forwarded. It should be possible to apply policies to allow
only some of the member PEs in the VPN to send or receive
traffic for a particular MAC address.

(R12c) A solution MUST be capable of supporting both inter-AS option-
C
option-C and inter-AS option-B scenarios as described in
[RFC4364].

11. Security Considerations

Any protocol extensions developed for the EVPN solution shall include
the appropriate security analysis. Besides the security requirements
covered in [RFC4761] and [RFC4762] when MAC learning is performed in
data-plane and in [RFC4364] when MAC learning is performed in control
plane, the following additional requirements need to be covered.

(R13) A solution MUST be capable of detecting and properly handling a
situation where the same MAC address appears behind two
different Ethernet Segment segments (whether inadvertently or
maliciously).

(R14) A solution MUST be capable of associating a MAC address to a
specific Ethernet Segment (sticky MAC) segment (aka "sticky MAC") in order to help
limit malicious traffic into a network for that MAC address.
This capability can limit the appearance of spoofed MAC address
addresses on a network. When this feature is enabled, the MAC
mobility for such sticky MAC addresses are disallowed disallowed, and the
traffic for such MAC addresses from any other Ethernet Segment segment
MUST be discarded.

12. Contributors

Samer Salam, Cisco, ssalam@cisco.com
John Drake, Juniper, jdrake@juniper.net
Clarence Filsfils, Cisco, cfilsfil@cisco.com

13. IANA Considerations

None.

14. Normative References

[802.1AX] IEEE, "IEEE Standard for Local and metropolitan area
networks - Link Aggregation", Std. 802.1AX-2008, IEEE
Computer Society, November 2008.

[802.1Q] IEEE, "IEEE Standard for Local and metropolitan area
networks - Virtual Bridged Local Area Networks", Std.
802.1Q-2011, 2011.

[G.8032] ITU-T, "Ethernet ring protection switching", ITU-T
Recommendation G.8032, February 2012.

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels",
August 1996. BCP 14, RFC 2119, March 1997.

[RFC4364] Bersani, F. and H. Tschofenig, "The EAP-PSK Protocol: A
Pre-Shared Key Extensible Authentication Protocol (EAP)
Method", RFC 4764, January 2007.

[RFC4761] Kompella, K. K., Ed., and Y. Rekhter, Ed., "Virtual Private
LAN Service (VPLS) Using BGP for Auto-Discovery and
Signaling", RFC 4761, January 2007.

[RFC4762] Lasserre, M. M., Ed., and V. Kompella, Ed., "Virtual Private
LAN Service (VPLS) Using Label Distribution Protocol (LDP)
Signaling", RFC 4762, January 2007.

[RFC4364] "BGP/MPLS IP Virtual Private Networks (VPNs)", February
2006.

[802.1AX] IEEE Std. 802.1AX-2008, "IEEE Standard for Local and
metropolitan area networks - Link Aggregation", IEEE
Computer Society, November 2008.

[802.1Q] IEEE Std. 802.1Q-2011, "IEEE Standard for Local and
metropolitan area networks - Virtual Bridged Local Area
Networks", 2011.

[RFC6074] E. Rosen and B. Rosen, E., Davie, B., Radoaca, V., and W. Luo,
"Provisioning, Auto-Discovery, and Signaling in Layer 2
Virtual Private Networks (L2VPNs)", RFC 6074, January
2011.

14.

13. Informative References
[RFC4664] "Framework for Layer 2 Virtual Private Networks (L2VPNs)",
September 2006.

[VPLS-BGP-MH] Kothari et al.,
Kothari, B., Kompella, K., Henderickx, W., Balue, F.,
Uttaro, J., Palislamovic, S., and W. Lin, "BGP based
Multi-homing in Virtual Private LAN Service", draft-ietf-l2vpn-vpls-multihoming-
06, work Work in progress, February,
Progress, July 2013.

[PWE3-ICCP] Martini et al.,
Martini, L., Salam, S., Sajassi, A., and S. Matsushima,
"Inter-Chassis Communication Protocol for L2VPN PE
Redundancy", draft-ietf-pwe3-iccp-13.txt, work Work in
progress, January, Progress, March 2014.

[VPLS-MCAST] R. Aggarwal, et al., "Multicast in VPLS", draft-ietf-
l2vpn-vpls-mcast-16.txt, work in progress, July 2013.

[MEF] Metro Ethernet Forum, "Ethernet Service Definitions", MEF
6.1 Technical Specification, "Ethernet Service
Definitions", April 2008.

[RFC4664] Andersson, L., Ed., and E. Rosen, Ed., "Framework for
Layer 2 Virtual Private Networks (L2VPNs)", RFC 4664,
September 2006.

[RFC6790] K. Kompella et al., Kompella, K., Drake, J., Amante, S., Henderickx, W., and
L. Yong, "The Use of Entropy Labels in MPLS Forwarding",
RFC 6790, November 2012.

15. Author's Address

[RFC7117] Aggarwal, R., Ed., Kamite, Y., Fang, L., Rekhter, Y., and
C. Kodeboniya, "Multicast in Virtual Private LAN Service
(VPLS)", RFC 7117, February 2014.

14. Contributors

Samer Salam, Cisco, ssalam@cisco.com
John Drake, Juniper, jdrake@juniper.net
Clarence Filsfils, Cisco, cfilsfil@cisco.com

Authors' Addresses

Ali Sajassi
Cisco
Email:
EMail: sajassi@cisco.com

Rahul Aggarwal
Arktan
Email:
EMail: raggarwa_1@yahoo.com

Wim Henderickx
Alcatel-Lucent
Email: wim.henderickx@alcatel-lucent.com

Aldrin Isaac
Bloomberg
Email: aisaac71@bloomberg.net

James Uttaro
AT&T
Email:
EMail: uttaro@att.com

Nabil Bitar
Verizon Communications
Email :
EMail: nabil.n.bitar@verizon.com

Wim Henderickx
Alcatel-Lucent
EMail: wim.henderickx@alcatel-lucent.com

Aldrin Isaac
Bloomberg
EMail: aisaac71@bloomberg.net