RSVP-TE Scalability - Recommendations

RSVP-TE [RFC3209] describes the use of standard RSVP [RFC2205] to establish Label Switched Paths (LSPs). As such, RSVP-TE inherited some properties of RSVP that adversely affect its control plane scalability. Specifically these properties are (a) reliance on periodic refreshes for state synchronization between RSVP neighbors and for recovery from lost RSVP messages, (b) reliance on refresh timeout for stale state cleanup, and (c) lack of any mechanisms by which a receiver of RSVP messages can apply back pressure to the sender(s) of these messages. Subsequent to [RFC2205] and [RFC3209] further enhancements to RSVP and RSVP-TE have been developed. In this document we describe how an implementation of RSVP-TE can use these enhancements to address the above mentioned properties to improve RSVP-TE control plane scalability.