The ability to compute constrained Traffic Engineering Label Switched Paths (TE LSPs) for point-to-multipoint (P2MP) LSPs in Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS) networks across multiple domains (where a domain is a collection of network elements within a common sphere of address management or path computational responsibility such as an IGP area or an Autonomous Systems) has been identified as a key requirement [PCEP-P2MP-REQ]. This document addresses this requirement by extending backward recursive path computation (BRPC) technique proposed for Point-to-Point (P2P) LSPs in [P2P-BRPC] for P2MP LSP path computation in a multiple domains network. Conventions used in this document In examples, "C:" and "S:" indicate lines sent by the client and server respectively.