http://www.rfc-editor.org/rfc/rfc5881.txt
RFC 5881: Bidirectional Forwarding Detection (BFD) for IPv4 and IPv6 (Single Hop), D. Katz, D. Ward2010-06-01T23:00:00-00:00This document describes the use of the Bidirectional Forwarding Detection (BFD) protocol over IPv4 and IPv6 for single IP hops. [STANDARDS-TRACK]