移动优先的智能内容获取与分发技术研究

The mobility is the core of the network design and service model in the future Internet. The efficient access to the content and the conservation to the network resources are the two key objectives for the optimization of the future Internet. Ten billions of mobile devices and user requirements bring a variety of challenges to the Internet, e.g., redundant transmissionn of the same content, the emergence of large volum of bursts of requests and invalid requests, etc., and degrades the efficiency of content request and dissemination. This project investigates content request and dissemination technologies in the presence of mobility-first, taking advantage of the mobility model of human and vehicles to produce various and varying requirements and minic the behavior of realistic characteristics of users in mobility-first environments. Moreover, we propose the cooperative content server selection algorithm and distributed dynamic content dissemination and migration algorithm, consider the network resources including network bandwidth, computing capability and storage capacity as the inputs for multi-objective optimization, and carry out the validation and evaluation of the developed algorithms by means of extensive simulation experiments, including the complexity of the algorithms, and the delay, throughput and loss probability of the content requests and dissemination. This project targets the future network with large volum of mobile devices. The application of the research results can change the service and communication models of the Internet fundamentally, and improve the quality of experience of the end-uers.

未来互联网应以移动作为网络设计和服务模式的核心，并以内容的高效获取和网络资源的节约为双重优化目标。百亿量级移动终端和用户需求给互联网带来了诸多挑战，如相同内容的冗余传输、大量突发请求和无效请求的出现，降低了内容获取与分发的效率。本项目研究面向移动优先环境的内容获取与分发技术，利用人与车辆的移动模型产生大量不同的、变化的需求，模拟移动优先环境中真实用户的行为特征，并提出协同内容服务器选择算法和分布式动态内容分发与迁移算法，基于网络带宽、计算、存储等资源进行多目标优化，通过模拟与仿真环境验证并评估算法的复杂度、获取与分发的时延、吞吐量、丢包率等重要指标。本项目面向海量移动设备涌现的未来，研究成果的应用可以从根本上改变互联网的服务模式和通信模式，全方位提升用户的服务质量体验。

未来互联网应以移动作为网络设计和服务模式的核心，并以内容的高效获取和网络资源的节约为双重优化目标。 但现有以内容为中心的网络对移动性的支持存在几个主要问题：1）对内容源移动支持不足；2）对高速移动用户的支持不足。这些问题导致面向移动优先环境的内容网络性能下降。因此课题组针对这些问题，提出了面向移动用户的协同内容获取算法以及面向移动内容源的动态内容获取与分发算法。项目开展期间，课题组共发表学术论文 13 篇，其中期刊论文 7 篇，包括国际著名期刊 ACM Transactions on Multimedia Computing, Communications, and Applications，国际会议论文 6 篇。在所有 13 篇论文中， 有 5 篇被 SCI 收录，11 篇被 EI 收录。此外，课题组还提交相关专利两项。