一种关注消息时效性的机会社会网络中节点传播能力分析模型

当前评估节点传播能力的工作大多针对静态网络.本文采用演化图模型对机会社会网络进行刻画,通过将传统通路(walk)的概念和静态图中的Katz中心性度量扩展到动态网络中,提出了一种基于历史相遇记录评估节点消息分发能力的方法.进一步,针对消息的时效性特性,本文提出了消息随时间推移效用递减的节点传播能力分析模型,该模型考虑了消息所有可能经历的空间和时间通路,并沿时间方向向下加权以描述消息时效性递减效应,可用于有效计算和预测节点的消息转发能力.本文的结论通过真实数据得到了验证.

An Analytical Model for Ranking the Candidates of Disseminating Time-Bound Messages in Opportunistic Mobile Social Networks

Traditional methods for evaluating node importance in sustaining the overall network topology or information dissemination are widely studied,while most of them are not applicable to dynamic settings where connections among nodes change frequently over time.This paper treats an opportunistic mobile social network as a time evolved,dynamic graph and proposes an effective scheme to calculate the relative nodal dissemination capability based on the contact history.In particular,we analyze the node importance in forwarding messages in more general settings where messages are time-dependent and become less important or out of date over time.To this end,we take a dynamic walk counting approach to calculate all possible temporal-spatial routes from a node to any other node by using a method of down-weighting of length.Since the age of a message increases with time,the old walks are discounted to represent the fading influence on the destination nodes.Experiments are conducted based on 4 real-world trace datasets,and the results show that our analytical result is effective at ranking the capabilities of nodes in disseminating or receiving the time-dependent messages.