NTU BcN ERC This draft describes the basic concepts of point-to-multipoint (p2mp) path computation on the basis of the Path Computation Element Metric Protocol (PCEMP). PCEMP, being soft-memory based, has the capability of dynamic configuration of its finite state machines (FSMs) in the participating PCEMP peers, and thus can support a wide variety of traffic engineering techniques that are needed to guarantee bandwidth demand and scalable fast protection and restoration in PCE based p2mp frameworks. To take advantage of bandwidth considerations and fast restoration mechanisms, the centralized Controller, which is the key element in a PCE node, is used for path computation in case of p2mp paths and can be used in a scenario where reliable multicasting of bandwidth-on-demand services becomes an important criteria for multiple-domain and/or inter-domain PCE based architectures.