Efficient Coding-Based Scheduling for Multi-Item Requests in Real-Time On-Demand Data Dissemination
Efficient Coding-Based Scheduling for Multi-Item Requests in Real-Time On-Demand Data Dissemination
复制标题
实时按需数据传播中多项目请求的高效基于编码的调度
DOI：
10.1155/2016/4320781
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发表时间：
2016
影响因子：
--
通讯作者：
Yu Zhengtao
中科院分区：
文献类型：
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作者：
Wang Shujuan;Yan Chunting;Yu Zhengtao
点播广播是一种有效的数据传播技术，可以增强系统处理动态客户端访问模式的能力。随着实时无线应用的发展，客户端在一次请求中请求多个具有时间限制的相关数据项是很现实的。对于实时数据广播，只有在过期之前可以被客户端接收到的项目才有用；否则，相关请求无效。因此，最小化错过截止日期的请求数量成为点播广播中的一项重要任务，特别是对于多项目场景，与单项目场景相比，由于工作量更大、复杂性更高，更多请求倾向于错过截止日期。在本文中，我们提出了一种基于网络编码的实时多项数据分发调度算法。所提出的算法利用缓存和请求的数据项之间的编码机会，并将网络编码与数据调度相结合，以最小化截止期限错过率。大量的仿真结果表明，所提出的算法在各种情况下都能实现最低的截止期限错过率。此外，证明了该算法在利用传输带宽方面的高效率，因为在时间限制内满足客户端请求时提供的无效服务实例较少。
On‐demand broadcast is an effective data dissemination technique to enhance the system ability to handle dynamic client access patterns. With the development of real‐time wireless applications, it is practical for clients to request multiple related data items with time constraint in one request. For real‐time data broadcast, items are only useful if they can be received by clients before expiration; otherwise, the related requests become invalid. Hence, minimizing the number of requests that miss their deadlines becomes an important task in on‐demand broadcast, especially for multi‐item scenario, where more requests are inclined to miss their deadlines due to the heavier workload and greater complexity, compared with single‐item scenario. In this paper, we propose a network coding‐based scheduling algorithm for real‐time multi‐item data dissemination. The proposed algorithm exploits the coding opportunities between cached and requested data items and integrates network coding with data scheduling to minimize the deadline miss ratio. Extensive simulation results demonstrate that the proposed algorithm achieves the lowest deadline miss ratio under various circumstances. In addition, the high efficiency of the proposed algorithm in utilizing the transmission bandwidth is proved for that fewer instances of ineffective service are provided for satisfying clients’ requests within time constraints.