Distributed wireless optical network online optimization based on network coding.

Recently, the hybrid wireless-optical broadband network integrating optical backbone networks, passive optical networks, and wireless access networks have been proposed to provide the high-bandwidth, low-cost, and ubiquitous communication connections. This paper considered the design of network coding-based multicast applications in such networks with the objective of maximizing the total network utility and minimizing the deployment cost. The problem was formulated as a mixed integer nonlinear programming problem and the exact solution is prohibitively complex. In order to make the problem more tractable, it developed a two-step optimization procedure that iteratively selected the optical network unit and gateways for the multicast sessions. During each iteration, it solved two subproblems a network coding design problem for the optical network and a user assignment and bandwidth allocation problem for the wireless network. The former was solved in a distributed way based on the Lagrangian-dual decomposition; the latter was solved based on the generalized bender decomposition. Simulation results illustrate the effectiveness of the proposed solutions. [ABSTRACT FROM AUTHOR]