RSVP scalability

RSVP Traffic Engineering (TE) protocol extensions for fast reroute (FRR) facility protection are introduced to allow greater scalability of LSPs and faster convergence times. RSVP-TE runs in enhanced FRR profile mode by default and includes FRR extensions as defined in RFC 2961. In mixed environments, where a subset of LSPs traverse nodes do not include this feature, RSVP-TE behavior is unchanged-backward compatibility is fundamentally supported in the design.