Internet L3 Vpn Design; Figure 6: Internet Vpn Created As Multihub-Spoke - Avaya 8600 Technical Configuration Manual

ensuring IP routing connectivity between VLANs assigned only to the same VRF instance but no IP
routing towards other IP Vlans assigned to other VRF instances. Each VRF will then have IPVPN
functionality enabled which will allow it to belong to one or more L3 VPNs. This configuration is done by
assigning an appropriate Route Distinguisher (RD) and import and export Route Targets (RT) to the VRF
IPVPN config. The end result being that BGP will automatically install remote IP routes from remote VRFs
belonging to the same VPN into the local VRF and vice-versa. Furthermore each L3 VPN can be created
as any-any, hub-spoke or multihub-spoke by simple manipulation of the import and export RTs as per
RFC4364 framework.

1.3.5 Internet L3 VPN design

FW1
Site1
Site4
The two ERS 8600s in the main Sites 1 & 2, will also have a third CLIP address (also a Service IP) which
will be made the same at both sites. This CLIP address will also use a 24 bit mask and will only be used
for IPinIP encapsulated L3 VPN traffic destined for the Internet. This will allow both the Site 1 ERS 8600
and Site 2 ERS 8600 to handle Internet bound traffic from any of Site 3, 4 or 5 regardless of the MLT
hash used by these SMLT edge Sites (i.e. eliminating the need for Site 1 to forward some Internet bound
traffic to Site 2 over the IST and vice-versa). To this effect RSMLT functionality will also be enabled on
Site 1 & 2 on the GRT OSPF VLANs. The Internet VPN will be configured as a multihub-spoke (dualhub-
spoke).
Network Design Implementation to Provide L2 & L3 VPN Connectivity
November 2010
Internet
DualHub&Spoke
IPVPN-Internet
OSPF Routed Core
IST MLT
BGP
Any-any
IPVPN-2

Figure 6: Internet VPN created as Multihub-Spoke

between Sites using SMLT and IPVPN-Lite for ERS 8600
Technical Configuration Guide
Site3
AS 65000
avaya.com
FW2
Site2
Site5
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