Optimum Planning of GMPLS Transport Networks

The rapid increase in the number of wavelengths per fiber has significantly increased the size of the optical crossconnect (OXC) in WDM transport networks. To maintain the scalability of the OXC at a reasonable level, various multi-granular OXC (MG-OXC) architectures have been proposed. Motivated by the fact that the MG-OXC constitutes only the optical segment of the generalized multi-protocol label switching (GMPLS)-based transport node architecture, we first propose a novel node architecture that handles the whole traffic hierarchy defined in GMPLS. Second, incorporating the proposed architecture with our novel contributions, namely (1) bifurcation of multi-granularity traffic demands; (2) traffic flow grouping strategies at all granularity levels, requires defining a new transport planning problem, which we call the routing and multi-granular paths assignment (RMGPA) problem. The RMGPA problem is formulated as a mixed integer linear programming (MILP) model with the objective of minimizing the overall network weighted port count