In this paper, a media distribution model, Active Control in an Intelligent and Distributed Environment (ACIDE), and solutions are proposed for video and audio livestreaming in mobile wireless networks. A base station and a cluster formed by a number of users are the essential components. Inside a cluster, users can establish peer to peer communications. The users that are members of a cluster are considered peers. This paper addresses the problem of minimizing the bandwidth allocated to a cluster of n peers such that a continuous media play of all the peers is guaranteed. The basic idea is to send the livestream media in packages. A media package is divided into n blocks. The distribution of blocks to the peers of a cluster follows a two-phase, multi-step approach. In phase 1 each peer receives one block with the optimal size from the base station. In phase 2, peers exchange their media blocks simultaneously in a few steps. Then the media package can be reconstructed and a live media can be played continuously. Allocated bandwidth, the amount of bandwidth the base station has to allocate to this cluster in order to play live streaming media without interruptions, is a function of many parameters such as the block sizes, download and upload bandwidth values of peers. This problem is formulated as an optimization problem. A solution is proposed to find the optimal block sizes such that the allocated bandwidth is minimized. Both theoretical model and simulations show that when the number of peers is large, the optimal allocated bandwidth approaches the lower bound that is the bandwidth required for multicasting. In other words, the allocated bandwidth may be reduced n times.
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