Adaptive Resource Allocation for Layer-Encoded IPTV Multicasting in IEEE 802.16 WiMAX Wireless Networks

In this paper, we study the utility-based resource allocation problem for layer-encoded IPTV multicast service over WiMAX networks. In this problem, each video stream is encoded into multiple layers. We regard each layer as a multicast subsession. Each layer of a video stream is assigned a utility value, and the number of layers for each program each user can receive is adjustable. The objective is to maximize the total utility (i.e., all users' satisfaction) and the system resource utilization, subject to users' channel conditions, the popularity of a video program, and the total available radio resource. We design a polynomial-time solution to this problem, and show that the difference in the performance of our proposed mechanism and the optimal solution is tightly bounded. Our mechanism supports both unicast and multicast, and both single layer and multi-layer environments. Most importantly, it can be integrated with the multicast mechanism defined in WiMAX standards, and can also be applied to any kind of wireless networks which support adaptive modulation and coding schemes. The performance of our scheme is evaluated by simulation. The simulation results show that this scheme can allocate resource flexibly according to the utility function of each program, the popularity of each program, and the amount of total resource available in the network.