A new functional model for management of optical transport network nodes

Pan-European WDM optical transport networks (OTN), as the supporting infrastructure for the push toward an "information society" will require new levels of management and supervision to ensure the quality of payload delivery. Several European funded projects such as MEPHISTO and MOON have addressed the needs for WDM-OTN Management Systems Support, proposing layered management object information models as a standard. This paper presents a functional model for the optical nodes of a transport network, from which we derive a new specialization. For the cross-connection fragment in the generic network information model, introducing the notion of status matrix (SM) to a new object class. This specialization allows for better management of optical cross-connects (OXC) even with reduced connection capabilities. The functional model could also be used in the optical control plane of the future automatic switched optical network (ASON). The SM is automatically derived from the routing control (RC) matrix, which represents all operational elements of the OXC available to establish any connection. The RC matrix is also automatically derived from the physical architecture using a functional routing description of the optical components. Examples of their utilization are presented and results given for two different routing strategies. First, a simple random decision is made whilst second a strategy called "Emptiest Status Matrix" (ESM) is adopted. The ESM algorithm results seem to support the choice of the SM model described as a strong candidate for better support in WDM-OTN OXC network element management.