To migrate from a non-confederation configuration to a confederation configuration requires
a major topology change and configuration modifications on each participating router.
Setting BGP policies to select an optimal path through a confederation requires other BGP
modifications.
There are no default confederations. Router confederations must be explicitly created.
Figure 2
Proxy ARP
Proxy ARP is the technique in which a router answers ARP requests intended for another
node. The router appears to be present on the same network as the "real" node that is the target
of the ARP and takes responsibility for routing packets to the "real" destination. Proxy ARP
can help nodes on a subnet reach remote subnets without configuring routing or a default
gateway.
Router Configuration Guide
•
Each sub-confederation (member) of the confederation has a different AS number.
The AS numbers used are typically in the private AS range of 64512 — 65535.
depicts a confederation configuration example.
Figure 2: Confederation Configuration
AS 100
ALA-A
Confederation 2002
AS 200
Confederation Member 1
ALA-B
ALA-C
ALA-D
AS 400
Confederation Member 2
AS 500
ALA-H
IP Router Configuration
AS 300
Confederation Member 3
ALA-E
ALA-F
ALA-G
SRSG005
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