http://www.rfc-editor.org/rfc/rfc5623.txt
RFC 5623: Framework for PCE-Based Inter-Layer MPLS and GMPLS Traffic Engineering, E. Oki, T. Takeda, JL. Le Roux, A. Farrel2009-09-01T23:00:00-00:00This document describes a framework for applying the PCE-based architecture to inter-layer Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS) traffic engineering. It provides suggestions for the deployment of PCE in support of multi-layer networks. This document also describes network models where PCE performs inter-layer traffic engineering, and the relationship between PCE and a functional component called the Virtual Network Topology Manager (VNTM). This memo provides information for the Internet community.