Implementation of UNI in optical multi-layer networks

The introduction of OIF UNI interfaces in GMPLS-controlled networks enables the dynamic and automatic establishment of connections triggered by client requests. Furthermore UNI interfaces can be used to interconnect server layers, e.g. for setting-up multi-layer networks consisting of a client layer and two or more server layers. This paper describes the design, implementation and test of a GMPLS/SDH prototype which provides UNI-N and UNI-C functionality simultaneously in a multi-layer network setup. Across the UNI-N interface the prototype receives connection requests from the client layer and across the UNI-C interfaces the prototype triggers a lower -layer connection setup if the available bandwidth is not sufficient to fulfil the client request. The prototype supports RSVP-TE as signalling protocol and OSPF-TE/CSPF as routing protocol. The automatically setup of lower-layer connections is realized by an automatic LSP controller. The proper functionality of the prototype has been verified in lab experiments using emulated client and server layers as well as in a field trial with real equipment and traffic.