Asymmetric Routing in BGP

Hello Narad

In this case you must deal with two things:

  1. Outgoing traffic
  2. Advertised prefixes for incoming traffic.

If we’re talking about running BGP at the edge of your network, then there are several things you can do. Always keep in mind that in such cases, you are always in control of outgoing traffic. You can route outgoing traffic however you like. Use PBR, use equal cost load balancing with BGP, or use primary and backup paths by modifying weight and other BGP attributes. Perform it in such a way so that you will have both redundancy, as well as high capacity, taking advantage of both links to the Internet.

Concerning the four prefixes you want to advertise, here you must decide how you want your incoming traffic to be distributed. How it will be distributed will affect how you advertise your prefixes. You must coordinate with your ISPs so that you will be getting the traffic you expect. Remember, that the ISPs have ultimate control over your incoming traffic, even though you can attempt to influence that incoming traffic in various ways. More about this can be found at the following post:

I hope this has been helpful!

Laz