3Com Switch 7700 Configuration Manual page 177

Configuring the BGP AS Confederation Attribute
Divide the following AS 100 into three sub-AS: 1001, 1002, and 1003, and
configure EBGP, confederation EBGP, and IBGP.
Figure 13 AS Confederation Configuration
AS1001 Switch A
172.68.10.1
172.68.10.3
156.10.1.1
156.10.1.2
Switch E
AS200
To configure the AS confederation:
1 Configure Switch A:
[Switch A] bgp 1001
[Switch A-bgp] confederation id 100
[Switch A-bgp] confederation peer-as 1002 1003
[Switch A-bgp] group confed1002 external
[Switch A-bgp] peer confed1002 as-number 1002
[Switch A-bgp] group confed1003 external
[Switch A-bgp] peer confed1003 as-number 1003
[Switch A-bgp] peer 172.68.10.2 group confed1002
[Switch A-bgp] peer 172.68.10.3 group confed1003
2 Configure Switch B:
[Switch B] bgp 1002
[Switch B-bgp] confederation id 100
[Switch B-bgp] confederation peer-as 1001 1003
[Switch B-bgp] group confed1001 external
[Switch B-bgp] peer confed1001 as-number 1001
[Switch B-bgp] group confed1003 external
[Switch B-bgp] peer confed1003 as-number 1003
[Switch B-bgp] peer 172.68.10.1 group confed1001
[Switch B-bgp] peer 172.68.10.3 group confed1003
3 Configure Switch C:
[Switch C] bgp 1003
[Switch C-bgp] confederation id 100
[Switch C-bgp] confederation peer-as 1001 1002
[Switch C-bgp] group confed1001 external
[Switch C-bgp] peer confed1001 as-number 1001
[Switch C-bgp] group confed1002 external
[Switch C-bgp] peer confed1002 as-number 1002
[Switch C-bgp] peer 172.68.10.1 group confed1001
[Switch C-bgp] peer 172.68.10.2 group confed1002
[Switch C-bgp] group ebgp200 external
[Switch C-bgp] peer 156.10.1.2 group ebgp200 as-number 200
[Switch C-bgp] group ibgp1003 internal
[Switch C-bgp] peer 172.68.1.2 group ibgp1003
AS100
Switch B
AS1002
172.68.10.2
Ethernet
172.68.1.1
172.68.1.2
Switch C Switch D
AS1003
BGP 169