Joint optimization of network coding and Aloha-based medium access control (MAC) for multi-hop wireless networks is considered. The multicast throughput with a power consumption-related penalty is maximized subject to flow conservation and MAC achievable rate constraints to obtain the optimal transmission probabilities. The relevant optimization problem is inherently non-convex and hence difficult to solve even in a centralized manner. A successive convex approximation technique is employed to obtain a Karush-Kuhn-Tucker solution. A separable problem structure is obtained and the dual decomposition technique is adopted to develop a distributed solution. The algorithm is thus applicable to large networks, and amenable to online implementation. Numerical tests verify performance and complexity advantages of the proposed approach over existing designs. A network simulation with implementation of random linear network coding shows performance very close to the one theoretically designed.
Bibliographical noteFunding Information:
Manuscript received 15 November 2010; revised 29 April 2011. This work was supported by NSF grants CCF-0830480, 1016605; and ECCS-0824007, 1002180; Part of this paper has been submitted to the 45th Annual Conference on Information Sciences and Systems, Princeton, NJ.
- Cross-layer optimization
- Network coding
- Random access