Juniper Networks Juniper Networks Juniper Networks AT&T Verizon This document describes the use of BGP as a control plane for networks that support Service Function Chaining (SFC). The document introduces a new BGP address family called the SFC AFI/SAFI with two route types. One route type is originated by a node to advertise that it hosts a particular instance of a specified service function. This route type also provides "instructions" on how to send a packet to the hosting node in a way that indicates that the service function has to be applied to the packet. The other route type is used by a Controller to advertise the paths of "chains" of service functions, and to give a unique designator to each such path so that they can be used in conjunction with the Network Service Header. This document adopts the SFC architecture described in RFC 7665.