3.7.i Describe BGP fast convergence features

3.7.i [i] Prefix independent convergence

The BGP Prefix Independent Convergence (PIC) improves convergence after a network failure. This convergence is applicable to both core and edge failures on IP and MPLS networks. You can use this feature to create and store an alternate path in the routing information base (RIB), forwarding information base (FIB) and the Cisco Express Forwarding (CEF). When a failure is detected, the alternate path immediately takes over, enabling fast failover.

These are the benefits of the feature:

● An alternate path for failover allows faster restoration of connectivity.

● Reduced traffic loss.

● Constant convergence time so that the switching time is the same for all prefixes.

Adam, Paul (2014-07-12). All-in-One CCIE V5 Written Exam Guide (Kindle Locations 4146-4147).  . Kindle Edition.

http://www.ietf.org/proceedings/85/slides/slides-85-rtgwg-10.pdf