China Telecom China Telecom Juniper Networks Futurewei ZTE Corporation Multicast forwarding requires per-tree state on certain nodes. Even with BIER, per-tree state is needed on ingress/egress BIER routers (though not needed on transit BIER routers). This documents specifies PCEP protocol to collect tree information (e.g. root, leaf, constraints) to allow a PCE to calculate a tree, and the procedures to set up per-tree forwarding state on relevant nodes for various multicast trees and various replication technologies.