Hi All,

This question asks to 'ensure that only directly connected clients of AS102
can transit AS50'.

AS101 - AS50 - AS102 - ASXXX

The DSG uses the following inbound as-path acl on the AS50 router peering
to AS102:

   ip as-path access-list 73 permit ^102(_[0-9]+?$

This filters the required routes entering AS50 from AS102 but there are no
outbound filters.

In the following topology, routes from AS101 could pass through AS50 to
AS102 and beyond.

AS101 - AS50 - AS102 - ASXXX - AS300

So while AS101 would not have a synchronous return route, AS300 could still
transit AS50 to reach AS101.

Given that changes can only be done on AS50, whats the best way to prevent
this?

Cheers
James
_______________________________________________
For more information regarding industry leading CCIE Lab training, please visit 
www.ipexpert.com

Are you a CCNP or CCIE and looking for a job? Check out 
www.PlatinumPlacement.com

To Unsubscribe from this list please visit the following link and follow the 
directions to unsubscribe. http://onlinestudylist.com/mailman/listinfo/ccie_rs

Reply via email to