基于SDN的无线网状网络缓存位置决策和操作分配方案

针对信息中心网络缓存管理效率较低的问题,提出一种旨在提高缓存管理效率的方法,且充分利用了无线网状网络(WMN)环境中软件定义网络(SDN)的概念。主要工作体现在SDN内容管理上,缓存位置决策考虑了网络拓扑位置、内容尺寸和缓存节点资源的位置。缓存操作考虑了请求客户端和缓存节点位置,且操作分为通过分支点的off-path缓存和通过缓存节点内容流的on-path缓存。控制器通过缓存内容表来确定工作的分配。实验在两种环境下进行:含有局部聚合客户端的小型网络和局部分布式客户端的大型网络。结果显示,所提方案仅利用每秒5.13kb的控制流量负荷即可将随机缓存位置方案的平均响应延迟减少23.95%。相比于其他网络缓存方案,所提方案最大化了WMN的节点缓存效率,明显提升了内容缓存分配性能,且系统没有较大的额外开销。

Cache Location Decision and Operating Allocation Schema Based on SDN in WMN

For the issue that cache management efficiency of information center network is low,a method was proposed to improve cache management efficiency,and the concept of software defined network (SDN) in the environment of wireless mesh network (WMN) was taken full use of.The main work is reflected in the SDN content management,in which the location of network topology,content size and the location of cache node resource are considered for cache location decision.The request of clients and the position of cache nodes are considered for cache operation,and the operation is divided into off-path caching through the branch point and on-path caching through cache node content streams.The controller determines the distribution of the allocation work by the cached content table.Experiments are carried out in two kinds of environments,small network where the clients are locally converged and large network where the clients are locally distributed.The proposed schemes decrease the average response delay by 23.95% with only 5.13kb control traffic load per second in comparison to random cache location scheme.Compared with other in-network cache schemes,the efficiency of the node cache in WMN is maximized,and the content cache allocation performance is significantly enhanced,also the system does not have a large number of additional overhead.