Internet DRAFT - draft-rabadan-nvo3-evpn-applicability
draft-rabadan-nvo3-evpn-applicability
NVO3 Workgroup J. Rabadan, Ed.
Internet Draft M. Bocci
Intended status: Informational Nokia
S. Boutros
WMware
A. Sajassi
Cisco
Expires: August 13, 2018 February 9, 2018
Applicability of EVPN to NVO3 Networks
draft-rabadan-nvo3-evpn-applicability-01
Abstract
In NVO3 networks, Network Virtualization Edge (NVE) devices sit at
the edge of the underlay network and provide Layer-2 and Layer-3
connectivity among Tenant Systems (TSes) of the same tenant. The NVEs
need to build and maintain mapping tables so that they can deliver
encapsulated packets to their intended destination NVE(s). While
there are different options to create and disseminate the mapping
table entries, NVEs may exchange that information directly among
themselves via a control-plane protocol, such as EVPN. EVPN provides
an efficient, flexible and unified control-plane option that can be
used for Layer-2 and Layer-3 Virtual Network (VN) service
connectivity. This document describes the applicability of EVPN to
NVO3 networks and how EVPN solves the challenges in those networks.
Status of this Memo
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. EVPN and NVO3 Terminology . . . . . . . . . . . . . . . . . . . 3
3. Why Is EVPN Needed In NVO3 Networks? . . . . . . . . . . . . . 6
4. Applicability of EVPN to NVO3 Networks . . . . . . . . . . . . 8
4.1. EVPN Route Types used in NVO3 Networks . . . . . . . . . . 8
4.2. EVPN Basic Applicability For Layer-2 Services . . . . . . . 9
4.2.1. Auto-Discovery and Auto-Provisioning of ES,
Multi-Homing PEs and NVE services . . . . . . . . . . . 10
4.2.2. Remote NVE Auto-Discovery . . . . . . . . . . . . . . . 11
4.2.3. Distribution Of Tenant MAC and IP Information . . . . . 12
4.3. EVPN Basic Applicability for Layer-3 Services . . . . . . . 13
4.4. EVPN as a Control Plane for NVO3 Encapsulations and
GENEVE . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.5. EVPN OAM and application to NVO3 . . . . . . . . . . . . . 15
4.6. EVPN as the control plane for NVO3 security . . . . . . . . 16
4.7. Advanced EVPN Features For NVO3 Networks . . . . . . . . . 16
4.7.1. Virtual Machine (VM) Mobility . . . . . . . . . . . . . 16
4.7.2. MAC Protection, Duplication Detection and Loop
Protection . . . . . . . . . . . . . . . . . . . . . . 16
4.7.3. Reduction/Optimization of BUM Traffic In Layer-2
Services . . . . . . . . . . . . . . . . . . . . . . . 17
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4.7.4. Ingress Replication (IR) Optimization For BUM Traffic . 18
4.7.5. EVPN Multi-homing . . . . . . . . . . . . . . . . . . . 18
4.7.6. EVPN Recursive Resolution for Inter-Subnet Unicast
Forwarding . . . . . . . . . . . . . . . . . . . . . . 19
4.7.7. EVPN Optimized Inter-Subnet Multicast Forwarding . . . 21
4.7.8. Data Center Interconnect (DCI) . . . . . . . . . . . . 21
5. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6. Conventions used in this document . . . . . . . . . . . . . . . 22
7. Security Considerations . . . . . . . . . . . . . . . . . . . . 22
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 22
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 22
9.1 Normative References . . . . . . . . . . . . . . . . . . . . 23
9.2 Informative References . . . . . . . . . . . . . . . . . . . 23
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 25
11. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 25
12. Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 25
1. Introduction
In NVO3 networks, Network Virtualization Edge (NVE) devices sit at
the edge of the underlay network and provide Layer-2 and Layer-3
connectivity among Tenant Systems (TSes) of the same tenant. The NVEs
need to build and maintain mapping tables so that they can deliver
encapsulated packets to their intended destination NVE(s). While
there are different options to create and disseminate the mapping
table entries, NVEs may exchange that information directly among
themselves via a control-plane protocol, such as EVPN. EVPN provides
an efficient, flexible and unified control-plane option that can be
used for Layer-2 and Layer-3 Virtual Network (VN) service
connectivity.
In this document, we assume that the EVPN control-plane module
resides in the NVEs. The NVEs can be virtual switches in hypervisors,
TOR/Leaf switches or Data Center Gateways. Note that Network
Virtualization Authorities (NVAs) may be used to provide the
forwarding information to the NVEs, and in that case, EVPN could be
used to disseminate the information across multiple federated NVAs.
The applicability of EVPN would then be similar to the one described
in this document. However, for simplicity, the description assumes
control-plane communication among NVE(s).
2. EVPN and NVO3 Terminology
o EVPN: Ethernet Virtual Private Networks, as described in [RFC7432].
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o PE: Provider Edge router.
o NVO3 or Overlay tunnels: Network Virtualization Over Layer-3
tunnels. In this document, NVO3 tunnels or simply Overlay tunnels
will be used interchangeably. Both terms refer to a way to
encapsulate tenant frames or packets into IP packets whose IP
Source Addresses (SA) or Destination Addresses (DA) belong to the
underlay IP address space, and identify NVEs connected to the same
underlay network. Examples of NVO3 tunnel encapsulations are VXLAN
[RFC7348], [GENEVE] or MPLSoUDP [RFC7510].
o VXLAN: Virtual eXtensible Local Area Network, an NVO3 encapsulation
defined in [RFC7348].
o GENEVE: Generic Network Virtualization Encapsulation, an NVO3
encapsulation defined in [GENEVE].
o CLOS: a multistage network topology described in [CLOS1953], where
all the edge switches (or Leafs) are connected to all the core
switches (or Spines). Typically used in Data Centers nowadays.
o ECMP: Equal Cost Multi-Path.
o NVE: Network Virtualization Edge is a network entity that sits at
the edge of an underlay network and implements L2 and/or L3 network
virtualization functions. The network-facing side of the NVE uses
the underlying L3 network to tunnel tenant frames to and from other
NVEs. The tenant-facing side of the NVE sends and receives Ethernet
frames to and from individual Tenant Systems. In this document, an
NVE could be implemented as a virtual switch within a hypervisor, a
switch or a router, and runs EVPN in the control-plane.
o EVI: or EVPN Instance. It is a Layer-2 Virtual Network that uses an
EVPN control-plane to exchange reachability information among the
member NVEs. It corresponds to a set of MAC-VRFs of the same
tenant. See MAC-VRF in this section.
o BD: or Broadcast Domain, it corresponds to a tenant IP subnet. If
no suppression techniques are used, a BUM frame that is injected in
a BD will reach all the NVEs that are attached to that BD. An EVI
may contain one or multiple BDs depending on the service model
[RFC7432]. This document will use the term BD to refer to a tenant
subnet.
o EVPN VLAN-based service model: it refers to one of the three
service models defined in [RFC7432]. It is characterized as a BD
that uses a single VLAN per physical access port to attach tenant
traffic to the BD. In this service model, there is only one BD per
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EVI.
o EVPN VLAN-bundle service model: similar to VLAN-based but uses a
bundle of VLANs per physical port to attach tenant traffic to the
BD. As in VLAN-based, in this model there is a single BD per EVI.
o EVPN VLAN-aware bundle service model: similar to the VLAN-bundle
model but each individual VLAN value is mapped to a different BD.
In this model there are multiple BDs per EVI for a given tenant.
Each BD is identified by an "Ethernet Tag", that is a control-plane
value that identifies the routes for the BD within the EVI.
o IP-VRF: an IP Virtual Routing and Forwarding table, as defined in
[RFC4364]. It stores IP Prefixes that are part of the tenant's IP
space, and are distributed among NVEs of the same tenant by EVPN.
Route-Distinghisher (RD) and Route-Target(s) (RTs) are required
properties of an IP-VRF. An IP-VRF is instantiated in an NVE for a
given tenant, if the NVE is attached to multiple subnets of the
tenant and local inter-subnet-forwarding is required across those
subnets.
o MAC-VRF: a MAC Virtual Routing and Forwarding table, as defined in
[RFC7432]. The instantiation of an EVI (EVPN Instance) in an NVE.
Route-distinghisher (RD) and Route-Target(s) (RTs) are required
properties of a MAC-VRF and they are normally different than the
ones defined in the associated IP-VRF (if the MAC-VRF has an IRB
interface).
o BT: a Bridge Table, as defined in [RFC7432]. A BT is the
instantiation of a BD in an NVE. When there is a single BD on a
given EVI, the MAC-VRF is equivalent to the BT on that NVE.
o AC: Attachment Circuit or logical interface associated to a given
BT. To determine the AC on which a packet arrived, the NVE will
examine the physical/logical port and/or VLAN tags (where the VLAN
tags can be individual c-tags, s-tags or ranges of both).
o IRB: Integrated Routing and Bridging interface. It refers to the
logical interface that connects a BD instance (or a BT) to an IP-
VRF and allows to forward packets with destination in a different
subnet.
o ES: Ethernet Segment. When a Tenant System (TS) is connected to one
or more NVEs via a set of Ethernet links, then that set of links is
referred to as an 'Ethernet segment'. Each ES is represented by a
unique Ethernet Segment Identifier (ESI) in the NVO3 network and
the ESI is used in EVPN routes that are specific to that ES.
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o DF and NDF: they refer to Designated Forwarder and Non-Designated
Forwarder, which are the roles that a given PE can have in a given
ES.
o VNI: Virtual Network Identifier. Irrespective of the NVO3
encapsulation, the tunnel header always includes a VNI that is
added at the ingress NVE (based on the mapping table lookup) and
identifies the BT at the egress NVE. This VNI is called VNI in
VXLAN or GENEVE, VSID in nvGRE or Label in MPLSoGRE or MPLSoUDP.
This document will refer to VNI as a generic Virtual Network
Identifier for any NVO3 encapsulation.
o BUM: Broadcast, Unknown unicast and Multicast frames.
o SA and DA: they refer to Source Address and Destination Address.
They are used along with MAC or IP, e.g. IP SA or MAC DA.
o RT and RD: they refer to Route Target and Route Distinguisher.
o PTA: Provider Multicast Service Interface Tunnel Attribute.
o RT-1, RT-2, RT-3, etc.: they refer to Route Type followed by the
type number as defined in the IANA registry for EVPN route types.
o TS: Tenant System.
o ARP and ND: they refer to Address Resolution Protocol and Neighbor
Discovery protocol.
3. Why Is EVPN Needed In NVO3 Networks?
Data Centers have adopted NVO3 architectures mostly due to the issues
discussed in [RFC7364]. The architecture of a Data Center is nowadays
based on a CLOS design, where every Leaf is connected to a layer of
Spines, and there is a number of ECMP paths between any two leaf
nodes. All the links between Leaf and Spine nodes are routed links,
forming what we also know as an underlay IP Fabric. The underlay IP
Fabric does not have issues with loops or flooding (like old Spanning
Tree Data Center designs did), convergence is fast and ECMP provides
a fairly optimal bandwidth utilization on all the links.
On this architecture and as discussed by [RFC7364] multi-tenant
intra-subnet and inter-subnet connectivity services are provided by
NVO3 tunnels, being VXLAN [RFC7348] or [GENEVE] two examples of such
tunnels.
Why is a control-plane protocol along with NVO3 tunnels required?
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There are three main reasons:
a) Auto-discovery of the remote NVEs that are attached to the same
VPN instance (Layer-2 and/or Layer-3) as the ingress NVE is.
b) Dissemination of the MAC/IP host information so that mapping
tables can be populated on the remote NVEs.
c) Advanced features such as MAC Mobility, MAC Protection, BUM and
ARP/ND traffic reduction/suppression, Multi-homing, Prefix
Independent Convergence (PIC) like functionality, Fast
Convergence, etc.
A possible approach to achieve points (a) and (b) above for
multipoint Ethernet services, is "Flood and Learn". "Flood and Learn"
refers to not using a specific control-plane on the NVEs, but rather
"Flood" BUM traffic from the ingress NVE to all the egress NVEs
attached to the same BD. The egress NVEs may then use data path MAC
SA "Learning" on the frames received over the NVO3 tunnels. When the
destination host replies back and the frames arrive at the NVE that
initially flooded BUM frames, the NVE will also "Learn" the MAC SA of
the frame encapsulated on the NVO3 tunnel. This approach has the
following drawbacks:
o In order to Flood a given BUM frame, the ingress NVE must know the
IP addresses of the remote NVEs attached to the same BD. This may
be done as follows:
- The remote tunnel IP addresses can be statically provisioned on
the ingress NVE. If the ingress NVE receives a BUM frame for the
BD on an ingress AC, it will do ingress replication and will send
the frame to all the configured egress NVE IP DAs in the BD.
- All the NVEs attached to the same BD can subscribe to an underlay
IP Multicast Group that is dedicated to that BD. When an ingress
NVE receives a BUM frame on an ingress AC, it will send a single
copy of the frame encapsulated into an NVO3 tunnel, using the
multicast address as IP DA of the tunnel. This solution requires
PIM in the underlay network and the association of individual BDs
to underlay IP multicast groups.
o "Flood and Learn" solves the issues of auto-discovery and learning
of the MAC to VNI/tunnel IP mapping on the NVEs for a given BD.
However, it does not provide a solution for advanced features and
it does not scale well.
EVPN provides a unified control-plane that solves the NVE auto-
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discovery, tenant MAP/IP dissemination and advanced features in a
scalable way and keeping the independence of the underlay IP Fabric,
i.e. there is no need to enable PIM in the underlay network and
maintain multicast states for tenant BDs.
Section 4 describes how to apply EVPN to meet the control-plane
requirements in an NVO3 network.
4. Applicability of EVPN to NVO3 Networks
This section discusses the applicability of EVPN to NVO3 networks.
The intend is not to provide a comprehensive explanation of the
protocol itself but give an introduction and point at the
corresponding reference document, so that the reader can easily find
more details if needed.
4.1. EVPN Route Types used in NVO3 Networks
EVPN supports multiple Route Types and each type has a different
function. For convenience, Table 1 shows a summary of all the
existing EVPN route types and its usage. We will refer to these route
types as RT-x throughout the rest of the document, where x is the
type number included in the first column of Table 1.
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+----+------------------------+-------------------------------------+
|Type|Description |Usage |
+----+------------------------+-------------------------------------+
|1 |Ethernet Auto-Discovery |Multi-homing: |
| | | Per-ES: Mass withdrawal |
| | | Per-EVI: aliasing/backup |
+----+------------------------+-------------------------------------+
|2 |MAC/IP Advertisement |Host MAC/IP dissemination |
| | |Supports MAC mobility and protection |
+----+------------------------+-------------------------------------+
|3 |Inclusive Multicast |NVE discovery and BUM flooding tree |
| |Ethernet Tag |setup |
+----+------------------------+-------------------------------------+
|4 |Ethernet Segment |Multi-homing: ES auto-discovery and |
| | |DF Election |
+----+------------------------+-------------------------------------+
|5 |IP Prefix |IP Prefix dissemination |
+----+------------------------+-------------------------------------+
|6 |Selective Multicast |Indicate interest for a multicast |
| |Ethernet Tag |S,G or *,G |
+----+------------------------+-------------------------------------+
|7 |IGMP Join Synch |Multi-homing: S,G or *,G state synch |
+----+------------------------+-------------------------------------+
|8 |IGMP Leave Synch |Multi-homing: S,G or *,G leave synch |
+----+------------------------+-------------------------------------+
|9 |Per-Region I-PMSI A-D |BUM tree creation across regions |
+----+------------------------+-------------------------------------+
|10 |S-PMSI A-D |Multicast tree for S,G or *,G states |
+----+------------------------+-------------------------------------+
|11 |Leaf A-D |Used for responses to explicit |
| | |tracking |
+----+------------------------+-------------------------------------+
Table 1 EVPN route types
4.2. EVPN Basic Applicability For Layer-2 Services
Although the applicability of EVPN to NVO3 networks spans multiple
documents, EVPN's baseline specification is [RFC7432]. [RFC7432]
allows multipoint layer-2 VPNs to be operated as [RFC4364] IP-VPNs,
where MACs and the information to setup flooding trees are
distributed by MP-BGP. Based on [RFC7432], [EVPN-OVERLAY] describes
how to use EVPN to deliver Layer-2 services specifically in NVO3
Networks.
Figure 1 represents a Layer-2 service deployed with an EVPN BD in an
NVO3 network.
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+--TS2---+
* | Single-Active
* | ESI-1
+----+ +----+
|BD1 | |BD1 |
+-------------| |--| |-----------+
| +----+ +----+ |
| NVE2 NVE3 NVE4
| EVPN NVO3 Network +----+
NVE1(IP-A) | BD1|=====+
+-------------+ RT-2 | | |
| +-MAC-VRF1+ | +-------+ +----+ |
| | +----+ | | |MAC1 | NVE5 TS3
TS1--------|BD1 | | | |IP1 | +----+ |
MAC1 | | +----+ | | |Label L|---> | BD1|=====+
IP1 | +---------+ | |NH IP-A| | | All-Active
| Hypervisor | +-------+ +----+ ESI-2
+-------------+ |
+--------------------------------------+
Figure 1 EVPN for L2 in an NVO3 Network - example
In a simple NVO3 network, such as the example of Figure 1, these are
the basic constructs that EVPN uses for Layer-2 services (or Layer-2
Virtual Networks):
o BD1 is an EVPN Broadcast Domain for a given tenant and TS1, TS2 and
TS3 are connected to it. The five represented NVEs are attached to
BD1 and are connected to the same underlay IP network. That is,
each NVE learns the remote NVEs' loopback addresses via underlay
routing protocol.
o NVE1 is deployed as a virtual switch in a Hypervisor with IP-A as
underlay loopback IP address. The rest of the NVEs in Figure 1 are
physical switches and TS2/TS3 are multi-homed to them. TS1 is a
virtual machine, identified by MAC1 and IP1.
4.2.1. Auto-Discovery and Auto-Provisioning of ES, Multi-Homing PEs and
NVE services
Auto-discovery is one of the basic capabilities of EVPN. The
provisioning of EVPN components in NVEs is significantly automated,
simplifying the deployment of services and minimizing manual
operations that are prone to human error.
These are some of the Auto-Discovery and Auto-Provisioning
capabilities available in EVPN:
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o Automation on Ethernet Segments (ES): an ES is defined as a group
of NVEs that are attached to the same TS or network. An ES is
identified by an Ethernet Segment Identifier (ESI) in the control
plane, but neither the ESI nor the NVEs that share the same ES are
required to be manually provisioned in the local NVE:
- If the multi-homed TS or network are running protocols such as
LACP (Link Aggregation Control Protocol), MSTP (Multiple-instance
Spanning Tree Protocol), G.8032, etc. and all the NVEs in the ES
can listen to the protocol PDUs to uniquely identify the multi-
homed TS/network, then the ESI can be "auto-sensed" or "auto-
provisioned" following the guidelines in [RFC7432] section 5.
- As described in [RFC7432], EVPN can also auto-derive the BGP
parameters required to advertise the presence of a local ES in
the control plane (RT and RD). Local ESes are advertised using
RT-4s and the ESI-import Route-Target used by RT-4s can be auto-
derived based on the procedures of [RFC7432], section 7.6.
- By listening to other RT-4s that match the local ESI and import
RT, an NVE can also auto-discover the other NVEs participating in
the multi-homing for the ES.
- Once the NVE has auto-discovered all the NVEs attached to the
same ES, the NVE can automatically perform the DF Election
algorithm (which determines the NVE that will forward traffic to
the multi-homed TS/network). EVPN guarantees that all the NVEs in
the ES have a consistent DF Election.
o Auto-provisioning of services: when deploying a Layer-2 Service for
a tenant in an NVO3 network, all the NVEs attached to the same
subnet must be configured with a MAC-VRF and the BD for the subnet,
as well as certain parameters for them. Note that, if the EVPN
service model is VLAN-based or VLAN-bundle, implementations do not
normally have a specific provisioning for the BD (since it is in
that case the same construct as the MAC-VRF). EVPN allows auto-
deriving as many MAC-VRF parameters as possible. As an example, the
MAC-VRF's RT and RD for the EVPN routes may be auto-derived.
Section 5.1.2.1 in [EVPN-OVERLAY] specifies how to auto-derive a
MAC-VRF's RT as long as VLAN-based service model is implemented.
[RFC7432] specifies how to auto-derive the RD.
4.2.2. Remote NVE Auto-Discovery
Auto-discovery via MP-BGP is used to discover the remote NVEs
attached to a given BD, NVEs participating in a given redundancy
group, the tunnel encapsulation types supported by an NVE, etc.
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In particular, when a new MAC-VRF and BD are enabled, the NVE will
advertise a new RT-3. Besides other fields, the RT-3 will encode the
IP address of the advertising NVE, the Ethernet Tag (which is zero in
case of VLAN-based and VLAN-bundle models) and also a PMSI Tunnel
Attribute (PTA) that indicates the information about the intended way
to deliver BUM traffic for the BD.
In the example of Figure 1, when MAC-VRF1/BD1 are enabled, NVE1 will
send an RT-3 including its own IP address, Ethernet-Tag for BD1 and
the PTA. Assuming Ingress Replication (IR), the RT-3 will include an
identification for IR in the PTA and the VNI the NVEs must use to
send BUM traffic to the advertising NVE. The other NVEs in the BD,
will import the RT-3 and will add NVE1's IP address to the flooding
list for BD1. Note that the RT-3 is also sent with a BGP
encapsulation attribute [TUNNEL-ENCAP] that indicates what NVO3
encapsulation the remote NVEs should use when sending BUM traffic to
NVE1.
Refer to [RFC7432] for more information about the RT-3 and forwarding
of BUM traffic, and to [EVPN-OVERLAY] for its considerations on NVO3
networks.
4.2.3. Distribution Of Tenant MAC and IP Information
Tenant MAC/IP information is advertised to remote NVEs using RT-2s.
Following the example of Figure 1:
o In a given EVPN BD, TSes' MAC addresses are first learned at the
NVE they are attached to, via data path or management plane
learning. In Figure 1 we assume NVE1 learns MAC1/IP1 in the
management plane (for instance, via Cloud Management System) since
the NVE is a virtual switch. NVE2, NVE3, NVE4 and NVE4 are TOR/Leaf
switches and they normally learn MAC addresses via data path.
o Once NVE1's BD1 learns MAC1/IP1, NVE1 advertises that information
along with a VNI and Next Hop IP-A in an RT-2. The EVPN routes are
advertised using the RD/RTs of the MAC-VRF where the BD belongs.
All the NVEs in BD1 learn local MAC/IP addresses and advertise them
in RT-2 routes in a similar way.
o The remote NVEs can then add MAC1 to their mapping table for BD1
(BT). For instance, when TS3 sends frames to NVE4 with MAC DA =
MAC1, NVE4 does a MAC lookup on the BT that yields IP-A and Label
L. NVE4 can then encapsulate the frame into an NVO3 tunnel with IP-
A as the tunnel IP DA and L as the Virtual Network Identifier. Note
that the RT-2 may also contain the host's IP address (as in the
example of Figure 1). While the MAC of the received RT-2 is
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installed in the BT, the IP address may be installed in the Proxy-
ARP/ND table (if enabled) or in the ARP/IP-VRF tables if the BD has
an IRB. See section 4.7.3. to see more information about Proxy-
ARP/ND and section 4.3. for more details about IRB and Layer-3
services.
Refer to [RFC7432] and [EVPN-OVERLAY] for more information about the
RT-2 and forwarding of known unicast traffic.
4.3. EVPN Basic Applicability for Layer-3 Services
[IP-PREFIX] and [INTER-SUBNET] are the reference documents that
describe how EVPN can be used for Layer-3 services. Inter Subnet
Forwarding in EVPN networks is implemented via IRB interfaces between
BDs and IP-VRFs. As discussed, an EVPN BD corresponds to an IP
subnet. When IP packets generated in a BD are destined to a different
subnet (different BD) of the same tenant, the packets are sent to the
IRB attached to local BD in the source NVE. As discussed in [INTER-
SUBNET], depending on how the IP packets are forwarded between the
ingress NVE and the egress NVE, there are two forwarding models:
Asymmetric and Symmetric.
The Asymmetric model is illustrated in the example of Figure 2 and it
requires the configuration of all the BDs of the tenant in all the
NVEs attached to the same tenant. In that way, there is no need to
advertise IP Prefixes between NVEs since all the NVEs are attached to
all the subnets. It is called Asymmetric because the ingress and
egress NVEs do not perform the same number of lookups in the data
plane. In Figure 2, if TS1 and TS2 are in different subnets, and TS1
sends IP packets to TS2, the following lookups are required in the
data path: a MAC lookup (on BD1's table), an IP lookup (on the IP-
VRF) and a MAC lookup (on BD2's table) at the ingress NVE1 and then
only a MAC lookup at the egress NVE. The two IP-VRFs in Figure 2 are
not connected by tunnels and all the connectivity between the NVEs is
done based on tunnels between the BDs.
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+-------------------------------------+
| EVPN NVO3 |
| |
NVE1 NVE2
+--------------------+ +--------------------+
| +---+IRB +------+ | | +------+IRB +---+ |
TS1-----|BD1|----|IP-VRF| | | |IP-VRF|----|BD1| |
| +---+ | | | | | | +---+ |
| +---+ | | | | | | +---+ |
| |BD2|----| | | | | |----|BD2|----TS2
| +---+IRB +------+ | | +------+IRB +---+ |
+--------------------+ +--------------------+
| |
+-------------------------------------+
Figure 2 EVPN for L3 in an NVO3 Network - Asymmetric model
In the Symmetric model, depicted in Figure 3, there are the same data
path lookups at the ingress and egress NVEs. For example, if TS1
sends IP packets to TS3, the following data path lookups are
required: a MAC lookup at NVE1's BD1 table, an IP lookup at NVE1's
IP-VRF and then IP lookup and MAC lookup at NVE2's IP-VRF and BD3
respectively. In the Symmetric model, the Inter Subnet connectivity
between NVEs is done based on tunnels between the IP-VRFs.
+-------------------------------------+
| EVPN NVO3 |
| |
NVE1 NVE2
+--------------------+ +--------------------+
| +---+IRB +------+ | | +------+IRB +---+ |
TS1-----|BD1|----|IP-VRF| | | |IP-VRF|----|BD3|-----TS3
| +---+ | | | | | | +---+ |
| +---+IRB | | | | +------+ |
TS2-----|BD2|----| | | +--------------------+
| +---+ +------+ | |
+--------------------+ |
| |
+-------------------------------------+
Figure 3 EVPN for L3 in an NVO3 Network - Symmetric model
The Symmetric model scales better than the Asymmetric model because
it does not require the NVEs to be attached to all the tenant's
subnets. However, it requires the use of NVO3 tunnels on the IP-VRFs
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and the exchange of IP Prefixes between the NVEs in the control
plane. EVPN uses RT-2 and RT-5 routes for the exchange of host IP
routes (in the case of RT-2 and RT-5) and IP Prefixes (RT-5s) of any
length. As an example, in Figure 3, NVE2 needs to advertise TS3's
host route and/or TS3's subnet, so that the IP lookup on NVE1's IP-
VRF succeeds.
[INTER-SUBNET] specifies the use of RT-2s for the advertisement of
host routes. Section 4.4.1 in [IP-PREFIX] specifies the use of RT-5s
for the advertisement of IP Prefixes in an "Interface-less IP-VRF-to-
IP-VRF Model".
4.4. EVPN as a Control Plane for NVO3 Encapsulations and GENEVE
[EVPN-OVERLAY] describes how to use EVPN for NVO3 encapsulations,
such us VXLAN, nvGRE or MPLSoGRE. The procedures can be easily
applicable to any other NVO3 encapsulation, in particular GENEVE.
The NVO3 working group has been working on different data plane
encapsulations. The Generic Network Virtualization Encapsulation
[GENEVE] has been recommended to be the proposed standard for NVO3
Encapsulation. The EVPN control plane can signal the GENEVE
encapsulation type in the BGP Tunnel Encapsulation Extended Community
(see [TUNNEL-ENCAP]).
The NVO3 encapsulation design team has made a recommendation in
[NVO3-ENCAP] for a control plane to:
1- Negotiate a subset of GENEVE option TLVs that can be carried on a
GENEVE tunnel
2- Enforce an order for GENEVE option TLVs and
3- Limit the total number of options that could be carried on a
GENEVE tunnel.
The EVPN control plane can easily extend the BGP Tunnel Encapsulation
Attribute sub-TLV [TUNNEL-ENCAP] to specify the GENEVE tunnel options
that can be received or transmitted over a GENEVE tunnels by a given
NVE. [EVPN-GENEVE] describes the EVPN control plane extensions to
support GENEVE.
4.5. EVPN OAM and application to NVO3
EVPN OAM (as in [EVPN-LSP-PING]) defines mechanisms to detect data
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plane failures in an EVPN deployment over an MPLS network. These
mechanisms detect failures related to P2P and P2MP connectivity, for
multi-tenant unicast and multicast L2 traffic, between multi-tenant
access nodes connected to EVPN PE(s), and in a single-homed, single-
active or all-active redundancy model.
In general, EVPN OAM mechanisms defined for EVPN deployed in MPLS
networks are equally applicable for EVPN in NVO3 networks.
4.6. EVPN as the control plane for NVO3 security
EVPN can be used to signal the security protection capabilities of a
sender NVE, as well as what portion of an NVO3 packet (taking a
GENEVE packet as an example) can be protected by the sender NVE, to
ensure the privacy and integrity of tenant traffic carried over the
NVO3 tunnels.
4.7. Advanced EVPN Features For NVO3 Networks
This section describes how EVPN can be used to deliver advanced
capabilities in NVO3 networks.
4.7.1. Virtual Machine (VM) Mobility
[RFC7432] replaces the traditional Ethernet Flood-and-Learn behavior
among NVEs with BGP-based MAC learning, which in return provides more
control over the location of MAC addresses in the BD and consequently
advanced features, such as MAC Mobility. If we assume that VM
Mobility means the VM's MAC and IP addresses move with the VM, EVPN's
MAC Mobility is the required procedure that facilitates VM Mobility.
According to [RFC7432] section 15, when a MAC is advertised for the
first time in a BD, all the NVEs attached to the BD will store
Sequence Number zero for that MAC. When the MAC "moves" within the
same BD but to a remote NVE, the NVE that just learned locally the
MAC, increases the Sequence Number in the RT-2's MAC Mobility
extended community to indicate that it owns the MAC now. That makes
all the NVE in the BD change their tables immediately with no need to
wait for any aging timer. EVPN guarantees a fast MAC Mobility without
flooding or black-holes in the BD.
4.7.2. MAC Protection, Duplication Detection and Loop Protection
The advertisement of MACs in the control plane, allows advanced
features such as MAC protection, Duplication Detection and Loop
Protection.
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[RFC7432] MAC Protection refers to EVPN's ability to indicate - in an
RT-2 - that a MAC must be protected by the NVE receiving the route.
The Protection is indicated in the "Sticky bit" of the MAC Mobility
extended community sent along the RT-2 for a MAC. NVEs' ACs that are
connected to subject-to-be-protected servers or VMs may set the
Sticky bit on the RT-2s sent for the MACs associated to the ACs. Also
statically configured MAC addresses should be advertised as Protected
MAC addresses, since they are not subject to MAC Mobility procedures.
[RFC7432] MAC Duplication Detection refers to EVPN's ability to
detect duplicate MAC addresses. A "MAC move" is a relearn event that
happens at an access AC or through an RT-2 with a Sequence Number
that is higher than the stored one for the MAC. When a MAC moves a
number of times N within an M-second window between two NVEs, the MAC
is declared as Duplicate and the detecting NVE does not re-advertise
the MAC anymore.
While [RFC7432] provides MAC Duplication Detection, it does not
protect the BD against loops created by backdoor links between NVEs.
However, the same principle (based on the Sequence Number) may be
extended to protect the BD against loops. When a MAC is detected as
duplicate, the NVE may install it as a black-hole MAC and drop
received frames with MAC SA and MAC DA matching that duplicate MAC.
Loop Protection is described in [LOOP].
4.7.3. Reduction/Optimization of BUM Traffic In Layer-2 Services
In BDs with a significant amount of flooding due to Unknown unicast
and Broadcast frames, EVPN may help reduce and sometimes even
suppress the flooding.
In BDs where most of the Broadcast traffic is caused by ARP (Address
Resolution Protocol) and ND (Neighbor Discovery) protocols on the
TSes, EVPN's Proxy-ARP and Proxy-ND capabilities may reduce the
flooding drastically. The use of Proxy-ARP/ND is specified in [PROXY-
ARP-ND].
Proxy-ARP/ND procedures along with the assumption that TSes always
issue a GARP (Gratuitous ARP) or an unsolicited Neighbor
Advertisement message when they come up in the BD, may drastically
reduce the unknown unicast flooding in the BD.
The flooding caused by TSes' IGMP/MLD or PIM messages in the BD may
also be suppressed by the use of IGMP/MLD and PIM Proxy functions, as
specified in [IGMP-MLD-PROXY] and [PIM-PROXY]. These two documents
also specify how to forward IP multicast traffic efficiently within
the same BD, translate soft state IGMP/MLD/PIM messages into hard
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state BGP routes and provide fast-convergence redundancy for IP
Multicast on multi-homed Ethernet Segments (ESes).
4.7.4. Ingress Replication (IR) Optimization For BUM Traffic
When an NVE attached to a given BD needs to send BUM traffic for the
BD to the remote NVEs attached to the same BD, IR is a very common
option in NVO3 networks, since it is completely independent of the
multicast capabilities of the underlay network. Also, if the
optimization procedures to reduce/suppress the flooding in the BD are
enabled (section 4.7.3), in spite of creating multiple copies of the
same frame at the ingress NVE, IR may be good enough. However, in BDs
where Multicast (or Broadcast) traffic is significant, IR may be very
inefficient and cause performance issues on virtual-switch-based
NVEs.
[OPT-IR] specifies the use of AR (Assisted Replication) NVO3 tunnels
in EVPN BDs. AR retains the independence of the underlay network
while providing a way to forward Broadcast and Multicast traffic
efficiently. AR uses AR-REPLICATORs that can replicate the
Broadcast/Multicast traffic on behalf of the AR-LEAF NVEs. The AR-
LEAF NVEs are typically virtual-switches or NVEs with limited
replication capabilities. AR can work in a single-stage replication
mode (Non-Selective Mode) or in a dual-stage replication mode
(Selective Mode). Both modes are detailed in [OPT-IR].
In addition, [OPT-IR] also describes a procedure to avoid sending
Broadcast, Multicast or Unknown unicast to certain NVEs that don't
need that type of traffic. This is done by enabling PFL (Pruned Flood
Lists) on a given BD. For instance, an virtual-switch NVE that learns
all its local MAC addresses for a BD via Cloud Management System,
does not need to receive the BD's Unknown unicast traffic. PFLs help
optimize the BUM flooding in the BD.
4.7.5. EVPN Multi-homing
Another fundamental concept in EVPN is multi-homing. A given TS can
be multi-homed to two or more NVEs for a given BD, and the set of
links connected to the same TS is defined as Ethernet Segment (ES).
EVPN supports single-active and all-active multi-homing. In single-
active multi-homing only one link in the ES is active. In all-active
multi-homing all the links in the ES are active for unicast traffic.
Both modes support load-balancing:
o Single-active multi-homing means per-service load-balancing
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to/from the TS, for example, in Figure 1, for BD1 only one of the
NVEs can forward traffic from/to TS2. For a different BD, the
other NVE may forward traffic.
o All-active multi-homing means per-flow load-balanding for unicast
frames to/from the TS. That is, in Figure 1 and for BD1, both
NVE4 and NVE5 can forward known unicast traffic to/from TS3. For
BUM traffic only one of the two NVEs can forward traffic to TS3,
and both can forward traffic from TS3.
There are two key aspects of EVPN multi-homing:
o DF (Designated Forwarder) election: the DF is the NVE that
forwards the traffic to the ES in single-active mode. In case of
all-active, the DF is the NVE that forwards the BUM traffic to
the ES.
o Split-horizon function: prevents the TS from receiving echoed BUM
frames that the TS itself sent to the ES. This is especially
relevant in all-active ESes, where the TS may forward BUM frames
to a non-DF NVE that can flood the BUM frames back to the DF NVE
and then the TS. As an example, in Figure 1, assuming NVE4 is the
DF for ES-2 in BD1, BUM frames sent from TS3 to NVE5 will be
received at NVE4 and, since NVE4 is the DF for DB1, it will
forward them back to TS3. Split-horizon allows NVE4 (and any
multi-homed NVE for that matter) to identify if an EVPN BUM frame
is coming from the same ES or different, and if the frame belongs
to the same ES2, NVE4 will not forward the BUM frame to TS3, in
spite of being the DF.
While [RFC7432] describes the default algorithm for the DF Election,
[HRW-DF], [PREF-DF] and [AC-DF] specify other algorithms and
procedures that optimize the DF Election.
The Split-horizon function is specified in [RFC7432] and it is
carried out by using a special ESI-label that it identifies in the
data path, all the BUM frames being originated from a given NVE and
ES. Since the ESI-label is an MPLS label, it cannot be used in all
the non-MPLS NVO3 encapsulations, therefore [EVPN-OVERLAY] defines a
modified Split-horizon procedure that is based on the IP SA of the
NVO3 tunnel, known as "Local-Bias". It is worth noting that Local-
Bias only works for all-active multi-homing, and not for single-
active multi-homing.
4.7.6. EVPN Recursive Resolution for Inter-Subnet Unicast Forwarding
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Section 4.3. describes how EVPN can be used for Inter Subnet
Forwarding among subnets of the same tenant. RT-2s and RT-5s allow
the advertisement of host routes and IP Prefixes (RT-5) of any
length. The procedures outlined by section 4.3. are similar to the
ones in [RFC4364], only for NVO3 tunnels. However, [EVPN-PREFIX] also
defines advanced Inter Subnet Forwarding procedures that allow the
resolution of RT-5s to not only BGP next-hops but also "overlay
indexes" that can be a MAC, a GW IP or an ESI, all of them in the
tenant space.
Figure 4 illustrates an example that uses Recursive Resolution to a
GWIP as per [IP-PREFIX] section 4.4.2. In this example, IP-VRFs in
NVE1 and NVE2 are connected by a SBD (Supplementary BD). An SBD is a
BD that connects all the IP-VRFs of the same tenant, via IRB, and has
no ACs. NVE1 advertises the host route TS2-IP/L (IP address and
Prefix Length of TS2) in an RT-5 with overlay index GWIP=IP1. Also,
IP1 is advertised in an RT-2 associated to M1, VNI-S and BGP next-hop
NVE1. Upon importing the two routes, NVE2 installs TS2-IP/L in the
IP-VRF with a next-hop that is the GWIP IP1. NVE2 also installs M1 in
the SBD, with VNI-S and NVE1 as next-hop. If TS3 sends a packet with
IP DA=TS2, NVE2 will perform a Recursive Resolution of the RT-5
prefix information to the forwarding information of the correlated
RT-2. The RT-5's Recursive Resolution has several advantages such as
better convergence in scaled networks (since multiple RT-5s can be
invalidated with a single withdrawal of the overlay index route) or
the ability to advertise multiple RT-5s from an overlay index that
can move or change dynamically. [EVPN-PREFIX] describes a few use-
cases.
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+-------------------------------------+
| EVPN NVO3 |
| +
NVE1 NVE2
+--------------------+ +--------------------+
| +---+IRB +------+ | | +------+IRB +---+ |
TS1-----|BD1|----|IP-VRF| | | |IP-VRF|----|BD3|-----TS3
| +---+ | |-(SBD)------(SBD)-| | +---+ |
| +---+IRB | |IRB(IP1/M1) IRB+------+ |
TS2-----|BD2|----| | | +-----------+--------+
| +---+ +------+ | |
+--------------------+ |
| RT-2(M1,IP1,VNI-S,NVE1)--> |
| RT-5(TS2-IP/L,GWIP=IP1)--> |
+-------------------------------------+
Figure 4 EVPN for L3 - Recursive Resolution example
4.7.7. EVPN Optimized Inter-Subnet Multicast Forwarding
The concept of the SBD described in section 4.7.6 is also used in
[OISM] for the procedures related to Inter Subnet Multicast
Forwarding across BDs of the same tenant. For instance, [OISM] allows
the efficient forwarding of IP multicast traffic from any BD to any
other BD (or even to the same BD where the Source resides). The
[OISM] procedures are supported along with EVPN multi-homing, and for
any tree allowed on NVO3 networks, including IR or AR. [OISM] also
describes the interoperability between EVPN and other multicast
technologies such as MVPN (Multicast VPN) and PIM for inter-subnet
multicast.
[EVPN-MVPN] describes another potential solution to support EVPN to
MVPN interoperability.
4.7.8. Data Center Interconnect (DCI)
Tenant Layer-2 and Layer-3 services deployed on NVO3 networks must be
extended to remote NVO3 networks that are connected via non-NOV3 WAN
networks (mostly MPLS based WAN networks). [EVPN-DCI] defines some
architectural models that can be used to interconnect NVO3 networks
via MPLS WAN networks.
When NVO3 networks are connected by MPLS WAN networks, [EVPN-DCI]
specifies how EVPN can be used end-to-end, in spite of using a
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different encapsulation in the WAN.
Even if EVPN can also be used in the WAN for Layer-2 and Layer-3
services, there may be a need to provide a Gateway function between
EVPN for NVO3 encapsulations and IPVPN for MPLS tunnels. [EVPN-IPVPN]
specifics the interworking function between EVPN and IPVPN for
unicast Inter Subnet Forwarding. If Inter Subnet Multicast Forwarding
is also needed across an IPVPN WAN, [OISM] describes the required
interworking between EVPN and MVPN.
5. Conclusion
EVPN provides a unified control-plane that solves the NVE auto-
discovery, tenant MAP/IP dissemination and advanced features required
by NVO3 networks, in a scalable way and keeping the independence of
the underlay IP Fabric, i.e. there is no need to enable PIM in the
underlay network and maintain multicast states for tenant BDs.
This document justifies the use of EVPN for NVO3 networks, discusses
its applicability to basic Layer-2 and Layer-3 connectivity
requirements, as well as advanced features such as MAC-mobility, MAC
Protection and Loop Protection, multi-homing, DCI and much more.
6. Conventions used in this document
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.
7. Security Considerations
This section will be added in future versions.
8. IANA Considerations
None.
9. References
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9.1 Normative References
[RFC7432] Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A.,
Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-Based Ethernet
VPN", RFC 7432, DOI 10.17487/RFC7432, February 2015, <http://www.rfc-
editor.org/info/rfc7432>.
[RFC7365] Lasserre, M., Balus, F., Morin, T., Bitar, N., and Y.
Rekhter, "Framework for Data Center (DC) Network Virtualization",
RFC 7365, DOI 10.17487/RFC7365, October 2014, <http://www.rfc-
editor.org/info/rfc7365>.
[RFC7364] Narten, T., Ed., Gray, E., Ed., Black, D., Fang, L.,
Kreeger, L., and M. Napierala, "Problem Statement: Overlays for
Network Virtualization", RFC 7364, DOI 10.17487/RFC7364, October
2014, <http://www.rfc-editor.org/info/rfc7364>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March
1997, <https://www.rfc-editor.org/info/rfc2119>.
[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>.
9.2 Informative References
[IP-PREFIX] Rabadan et al., "IP Prefix Advertisement in EVPN",
draft-ietf-bess-evpn-prefix-advertisement-08, work in progress,
October, 2017.
[INTER-SUBNET] Sajassi et al., "IP Inter-Subnet Forwarding in EVPN",
draft-ietf-bess-evpn-inter-subnet-forwarding-03, work in progress,
February, 2017
[EVPN-USAGE] Rabadan et al., "Usage and applicability of BGP MPLS
based Ethernet VPN", work in progress, draft-ietf-bess-evpn-usage-06,
August 2017
[EVPN-OVERLAY] Sajassi-Drake et al., "A Network Virtualization
Overlay Solution using EVPN", work in progress, draft-ietf-bess-
evpn-overlay-08, March 2017
[GENEVE] Gross et al., "Geneve: Generic Network Virtualization
Encapsulation", draft-ietf-nvo3-geneve-05, work in progress,
September 2017
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[NVO3-ENCAP] Boutros et al., "NVO3 Encapsulation Considerations",
draft-ietf-nvo3-encap-01, work in progress, October 2017
[TUNNEL-ENCAP] Rosen et al., "The BGP Tunnel Encapsulation
Attribute", draft-ietf-idr-tunnel-encaps-03, work in progress, May
31, 2016.
[EVPN-LSP-PING] Jain et al., "LSP-Ping Mechanisms for EVPN and PBB-
EVPN", draft-jain-bess-evpn-lsp-ping-05, work in progress, July 2017
[LOOP] Rabadan et al., "Loop Protection in EVPN networks", draft-
snr-bess-evpn-loop-protect-00, work in progress, July 2017
[PROXY-ARP-ND] Rabadan et al., "Operational Aspects of Proxy-ARP/ND
in EVPN Networks", draft-ietf-bess-evpn-proxy-arp-nd-03, work in
progress, October 2017
[IGMP-MLD-PROXY] Sajassi et al., "IGMP and MLD Proxy for EVPN",
draft-ietf-bess-evpn-igmp-mld-proxy-00, work in progress, March 2017
[PIM-PROXY] Rabadan et al., "PIM Proxy in EVPN Networks", draft-skr-
bess-evpn-pim-proxy-01, work in progress, October 2017
[OPT-IR] Rabadan et al., "Optimized Ingress Replication solution for
EVPN", draft-ietf-bess-evpn-optimized-ir-02, work in progress, August
2017
[HRW-DF] Mohanty et al., "A new Designated Forwarder Election for
the EVPN", draft-ietf-bess-evpn-df-election-03, work in progress,
October 2017
[PREF-DF] Rabadan et al., "Preference-based EVPN DF Election",
draft-ietf-bess-evpn-pref-df-00, work in progress, June 2017
[AC-DF] Rabadan et al., "AC-Influenced Designated Forwarder Election
for EVPN", draft-ietf-bess-evpn-ac-df-02, work in progress, October
2017
[OISM] Lin at al., "EVPN Optimized Inter-Subnet Multicast (OISM)
Forwarding", draft-lin-bess-evpn-irb-mcast-04, work in progress,
October 2017
[EVPN-DCI] Rabadan et al., "Interconnect Solution for EVPN Overlay
networks", draft-ietf-bess-dci-evpn-overlay-05, work in progress,
July 2017
[BUM-UPDATE] Zhang et al., "Updates on EVPN BUM Procedures", draft-
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ietf-bess-evpn-bum-procedure-updates-02, work in progress, September
2017
[EVPN-IPVPN] Rabadan-Sajassi et al., "EVPN Interworking with IPVPN",
draft-rabadan-sajassi-bess-evpn-ipvpn-interworking-00, work in
progress, October 2017
[RFC7348] Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger,
L., Sridhar, T., Bursell, M., and C. Wright, "Virtual eXtensible
Local Area Network (VXLAN): A Framework for Overlaying Virtualized
Layer 2 Networks over Layer 3 Networks", RFC 7348, DOI
10.17487/RFC7348, August 2014, <http://www.rfc-
editor.org/info/rfc7348>.
[RFC7510] Xu, X., Sheth, N., Yong, L., Callon, R., and D. Black,
"Encapsulating MPLS in UDP", RFC 7510, DOI 10.17487/RFC7510, April
2015, <http://www.rfc-editor.org/info/rfc7510>.
[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February 2006,
<http://www.rfc-editor.org/info/rfc4364>.
[CLOS1953] Clos, C., "A Study of Non-Blocking Switching Networks",
The Bell System Technical Journal, Vol. 32(2), DOI 10.1002/j.1538-
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[EVPN-GENEVE] Boutros et al., "EVPN control plane for Geneve",
draft-boutros-bess-evpn-geneve-01, work in progress, February 2018.
[EVPN-MVPN] Sajassi et al., "Seamless Multicast Interoperability
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10. Acknowledgments
11. Contributors
12. Authors' Addresses
Jorge Rabadan (Editor)
Nokia
777 E. Middlefield Road
Mountain View, CA 94043 USA
Rabadan et al. Expires August 13, 2018 [Page 25]
Internet-Draft EVPN Applicability for NVO3 February 9, 2018
Email: jorge.rabadan@nokia.com
Sami Boutros
VMware
Email: sboutros@vmware.com
Matthew Bocci
Nokia
Email: matthew.bocci@nokia.com
Ali Sajassi
Cisco
Email: sajassi@cisco.com
Rabadan et al. Expires August 13, 2018 [Page 26]