Information Technology Reference
In-Depth Information
These conditions are met automatically if CLNS is enabled on the interface between the
routers and the eBGP session is formed between them, with NLRI exchange taking place.
The inclusion of R1's NSAP in R2's L2 LSP provides R3 with next-hop reachability for
any iBGP learned prefixes that use R1 as the next hop. If the ES-IS adjacency or eBGP
peering session between R1 and R2 goes down, the prefix for R1's NSAP is removed from
R2's L2 LSP.
Multiprotocol BGP for CLNS Configuration Example
This example focuses specifically on BGP configuration aspects. A four-router core net-
work and two aggregation routers in different autonomous systems provide the sample
topology, as shown in Figure A-5.
Sample Network Topology
Figure A-5
AS 65102
R4
47.5678.5678.5678.5678.00
R2
AS 65101
R6
R10
AS 65100
47.1234.1234.1234.1234.00
.5
.6
172.16.1.4/30
R11
R1
R3
R5
The NSAP addressing is shown in Table A-1.
CLNS Addressing for the Sample Network
Table A-1
Router
NSAP
R1
47.1111.1111.1111.1111.00
R2
47.2222.2222.2222.2222.00
R3
47.3333.3333.3333.3333.00
R4
47.4444.4444.4444.4444.00
R5
47.5555.5555.5555.5555.00
R6
47.6666.6666.6666.6666.00
R10
47.5678.5678.5678.5678.00
R11
47.1234.1234.1234.1234.00
