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.

翻译：本文提出了一种名为“智能分布式环境中的主动控制”（ACIDE）的媒体分发模型及解决方案，用于移动无线网络中的视频和音频直播。基站与多个用户组成的簇是核心组件。在簇内，用户之间可建立点对点通信，簇成员被视为对等节点。本文旨在解决最小化分配给n个对等节点簇的带宽问题，以保证所有节点能连续播放媒体。基本思路是将直播流媒体分块传输：一个媒体包被分割成n个数据块，数据块的分发采用两阶段多步骤方法。第一阶段，每个节点从基站接收一个最优大小的数据块；第二阶段，节点间通过少量步骤同步交换数据块。随后媒体包可被重构，实现直播媒体的连续播放。分配带宽（基站为确保无中断直播必须分配给该簇的带宽量）取决于块大小、节点上传/下载带宽值等多个参数。该问题被建模为优化问题，并提出了求解最优块大小以最小化分配带宽的解决方案。理论模型与仿真均表明，当对等节点数量较大时，最优分配带宽趋近于组播所需带宽的下界，即分配带宽可降低至原来的n分之一。