基于最大最小蚂蚁系统的容迟网络缓存机制

Caching Mechanism Based on Max-Min Ant System inDelay Tolerant Network

容迟网络(Delay Tolerant Network, DTN)是指节点资源紧张、网络延迟较大或链接频繁中断的网络结构。为保障消息到达率,DTN采用了缓存机制,导致网络开销大幅提升。为了在提升消息到达率的同时降低网络开销,通过考虑消息类别,将蚁群算法引入容迟网络缓存机制中,提出了基于最大最小蚂蚁系统的容迟网络缓存机制。在该机制中,节点致力于维护消息的信息素浓度,依据消息的类别及自身属性得到消息的丢弃权重,进而实现容迟网络的消息丢弃。实验结果表明,与基于传统蚁群算法的容迟网络缓存机制相比,所提的容迟网络缓存机制提高了7.7%的消息到达率并降低了5.4%的网络开销。

Delay Tolerant Network(DTN)indicates a network structure where node resources are scarce,network latency is high,or links are frequently interrupted.To guarantee message delivery,DTN employs a caching mechanism which leads to an extra increase of network overhead.To improve message delivery rate and reduce network overhead,this paper considers message categories,and utilizes an ant colony algorithm to improve DTN caching mechanism.The proposed DTN caching mechanism is termed as maximum minimum ant system.In this mechanism,nodes focus on maintaining the pheromone concentration of the message.Specifically,nodes determine the discarding weight of message based on its category and own attributes to discard messages in the DTN.Experimental results demonstrate that compared with the DTN caching mechanism based on traditional ant colony algorithms,the proposed DTN caching mechanism increases the message delivery rate by 7.7%and reduces network overhead by 5.4%.