Multihop EBGP

The common eBGP is over single link. Sometimes may be multi links using on eBGP peering. R2 update NetA and NetB via eBGP peer to R1. If you always want to put NetA into link 1 and NetB into link2 plus redundancy @R1. If any one link down must not impact the traffic.

The redundancy is the big topic in multihop eBGP. What I mean is if F0/0.12 @R1 is down, the traffic will move to F0/0.112 to R2. This is not so hard in Junos. The Junos software can create one more routing table for certain type traffic by using FBF. But in IOS, it's not easy. So I found aonther way to accomplish this.

I will post the answer later. If you have any idea, Let me know.

CLNS

What is CLNS ? The answer is "Connectionless Network Service" It's different from IP. This is one of the issue for Juniper router. Because Juniper router doesn't support CLNS routing in M/T and static route support in J series. And In cisco IOS router you can run DUAL ISIS at the saem time.

Take a look. From JNCIP book :

"Juniper Networks M-series routers support the IS-IS protocol strictly for use in building IP routing tables. There is no support for the routing of OSI Connectionless Network Service (CLNS) network layer packets."

http://www.juniper.net/techpubs/software/jseries/junos93/jseries-config-guide-advanced/configuring-is-is-for-clns.html

This help you Configuring IS-IS for CLNS.