Gre Tunnel Features - Alcatel-Lucent OmniAccess 700 Cli Configuration Manual

GRE T F
UNNEL EATURES
In addition to the above concepts, some important features should be highlighted:
T S
OPOLOGY AND CALABILITY
Due to the flexible nature of GRE, tunnels can be established in different
topologies.
The use of different topologies also allows GRE tunnels to be scaled
appropriately. Specifically, a hierarchical structure allows a core to be constructed
by connecting core routers together with GRE tunnels. From that core, additional
tunnels can be provisioned to the provider edge routers.
S C
EPARATION OF USTOMER AND
In OA-700, OSPF protocol instances operate upon their own instance of the
routing table. Routes from one routing table instance are not visible to the other
routing table instance unless it is explicitly redistributed. Therefore, even though
customer routes are present in our routing table, they will not be picked up by the
provider OSPF instance.
Therefore, it is possible for us to have independent OSPF routing instances for
the VPN going over the tunnel, and the connectivity to the provider network.
In terms of BGP, it is possible to run BGP over the VPN by specifying a peer IP
address that is reachable over the tunnel. This will guarantee that all the BGP
messages to the peer will go over the tunnel.
F GRE
ILTERS ON TUNNELS
Filters are packet filters which determine whether packets are forwarded or
dropped. They are useful for security or policy purposes. The header in each
packet is examined and the relevant criteria include source and destination
address, source and destination port, or other information. Filters can be applied
to GRE tunnel interfaces, which means that packet filtering with its corresponding
benefits can be offered for GRE tunnels.
CLI Configuration Guide
Beta
Except on the first page, right running head:
Heading1 or Heading1NewPage text (automatic)
F
EATURES
P R
ROVIDER OUTING
Alcatel-Lucent
GRE Overview
839
Beta