Ciena Arrcus, Inc HPE Bloomberg L.P. This document specifies extensions to RFC4271 BGP-4 that enable a BGP speaker to negotiate additional Bidirectional Forwarding Detection (BFD) extensions using a BGP capability. This BFD Strict-Mode Capability enables a BGP speaker to prevent a BGP session from being established until a BFD session is established. This is referred to as BFD "strict-mode".