Overview; Ipvpn-Lite Brief Overview; Requirements - Avaya 8600 Technical Configuration Manual

1. Overview

This Technical Configuration Guide (TCG) provides an example of how to design and implement a
network design to provide both L2 and L3 VPN capability between a number of different sites for the
Avaya Ethernet Routing Switch (ERS) 8600 software release version 5.0.x.
The design combines Avaya's unique SMLT Clustering and IPVPN-Lite capability to provide simple L2
connectivity across the core as well as fully featured RFC4364* L3 VPNs over an IP transport. This
provides for a resilient and robust design featuring sub-second failover without having to use any
Spanning Tree Protocol anywhere in the network as well as a much simpler and cost-effective design
alternative to MPLS based L3 & L2 VPNs.
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* BGP/MPLS IP VPNs were first defined in RFC2547. RFC4364 obsoletes RFC2547
The design is based on Avaya Ethernet Routing Switch (ERS) 8600.

1.1 IPVPN-Lite brief overview

Avaya's IPVPN-Lite is based on RFC4364 BGP/MPLS IP VPNs. At the control plane level, IPVPN-Lite is
identical to RFC4364. A single instance of BGP running in the backbone is used to re-advertise IPv4
routes belonging to all L3 VPNs. These routes are advertised by BGP as VPNv4 routes and are installed
in VRF (VPN Routing & Forwarding) tables where the L3 VPNs are terminated. A VRF is simply a
virtualized IP routing instance which can be configured on the switch.
The difference between IPVPN-Lite and MPLS based RFC4364 IPVPNs is in the data plane layer where
IPVPN-Lite uses a simple IPinIP encapsulation instead of pushing MPLS labels [1].
IPVPN-Lite has thus a number of benefits over MPLS based RFC4364 VPNs:
 RFC4364 L3 VPN functionality is available without having to deploy MPLS across the backbone
 Since MPLS is not required, no complex Label Distribution Protocol (LDP /RSVP-TE) is required either
 IPVPN-Lite can be deployed over existing IP routed backbones
 IPVPN-Lite is simpler to deploy, troubleshoot and maintain
 IPVPN-Lite can be deployed above an SMLT Core
IPVPN-Lite can therefore offer the full functionality of RFC4364 BGP L3 VPNs over an SMLT/IP
backbone, with none of the drawbacks of having to deploy a costly/complex MPLS backbone.

1.2 Requirements

In this example, the requirements for this design are based on the following:
 5 separate Sites need to be interconnected (as shown in figure 1)
 10 Gigabit connectivity between sites (over dark fiber or DWDM circuits)
 Capability of L2 VPN connectivity between any number of Sites
 Capability of L3 VPN connectivity between any number of Sites
 VPN scalability to scale up to ~100 L2 VPNs and ~100 L3 VPNs
Network Design Implementation to Provide L2 & L3 VPN Connectivity
November 2010
between Sites using SMLT and IPVPN-Lite for ERS 8600
Technical Configuration Guide
avaya.com
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