Single-hop BFD sessions for pseudowire redundant logical interfaces

Inline distribution of single-hop Bidirectional Forwarding Detection [protocol] (BFD) sessions for pseudowire subscriber logical tunnel interfaces by default, as these interfaces are anchored on a single Flexible PIC Concentrator (FPC). With pseudowire redundant logical interfaces, the member logical tunnel interfaces can be hosted on different linecards. As a result, single-hop BFD sessions are operated in a centralized mode because the distribution address is not available for these logical interfaces. Inline distribution of single-hop BFD sessions is extended to pseudowire subscriber over redundant logical tunnel interfaces, thereby improving the scaling (number of sessions) and performance (detection time) of single-hop BFD sessions.