Ericsson Ericsson Alcatel-Lucent Alcatel-Lucent This document describes requirements for MRN application to multiple hierarchies of technologies (e.g. OTN, SDH, ETH). For this purpose, after summarizing MRN definitions, rationales and currently supported applications, a problem statement is introduced together with its implications on GMPLS routing and signaling. New functional requirements are derived and MRN extensions required to address them are identified.