In a Cisco or Juniper M/T environment that is using RSVP-TE signaling to establish TE LSPs, MPLS Manager matches various attributes (LocalAddress, FromIP, ToIP) that are associated with the RsvpProtocolEndpoints that are discovered on different PE and P devices, and creates an RsvpSession instance for each complementary match.

An RsvpSession is ConnectedTo two RsvpProtocolEndpoints, where one RsvpProtocolEndpoint is HostedBy one PE or P device, and the second is HostedBy a peering PE or P device. The RsvpSession provides a bidirectional signaling path through which the two peering devices exchange MPLS label information for the purpose of constructing, maintaining, or deleting TE LSPs or subLSPs.