Conference Paper

A Suboptimal Network Utility Maximization Approach for Scalable Multimedia Applications.

Sch. of Comput. Sci., IPM, Tehran, Iran
DOI: 10.1109/GLOCOM.2009.5425607 Conference: Proceedings of the Global Communications Conference, 2009. GLOBECOM 2009, Honolulu, Hawaii, USA, 30 November - 4 December 2009
Source: IEEE Xplore

ABSTRACT Wired and wireless data networks have witnessed an explosive growth of inelastic traffics such as real-time or media streaming applications. Recently, applications relying on layered encoding schemes appeared in the context of live-streaming and video and audio delivery applications. This paper addresses the Network Utility Maximization (NUM) for scalable multimedia transmission which is relying on layered encoding schemes. Nonconvexity of the NUM problem for such applications makes dual-based approaches incompetent, whereby achieving optimality proves quite challenging. We adopt the staircase utility function and formulate the underlying optimization problem. To tackle the non-convexity of the problem, we use a smooth approximation of the staircase utility function and propose a dual-based distributed algorithm for rate allocation and bandwidth sharing in such scenarios. Numerical results show that the proposed algorithm achieves suboptimal yet efficient solution.

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