Chapter 20. Merging BGP Autonomous Systems

It would be nice to be able to plan your network from scratch, taking into account scalability, of course, and to never have to worry about dealing with mergers, or kludges, or one-offs, but that never happens. Sometimes you will be required to bring another network into the fold no matter how messed up you perceive the other network to be.

Although the migration of the Interior Gateway Protocol (IGP) is vital to internal connectivity, errors in Border Gateway Protocol (BGP) can lead not only to internal routing issues, but also to external routing issues that could thrust your network into the listserv annals of groups such as the North American Network Operators Group, which researches, comments on, and, if necessary, sanctions networks affecting Internet routing, or the high availability posture of networks managed by NANOG members.