摘要
针对命名数据网络(named data networking,NDN)移动性增强支持不足的问题,基于城区移动场景提出了一种基于移动预测的内容预取方法(mobility-aware prediction approach for content prefetching,MAP-CP)及扩展方案(extended MAP-CP,e MAP-CP)。MAP-CP和e MAP-CP通过预测移动用户的下一接入点(access point,AP),预取在当前AP下因切换AP不能获取到的数据并缓存到所预测的下一AP相关联的NDN节点中,为切换AP后的移动用户就近服务,达到降低内容获取延迟和提高响应率的目的。e MAP-CP在MAP-CP的基础上,可预取切换AP过程中请求的数据,能够进一步提高性能。基于ndn SIM的仿真实验表明,与NDN本身相比,MAP-CP和e MAP-CP具有更低的平均内容获取延迟和更高的响应率,而且e MAP-CP更优。在移动速度为20 m/s、发包速率为200 pps时,MAP-CP和e MAP-CP的平均内容获取延迟可分别降低约4.0%和38.7%,响应率可分别提高约1.2%和4.9%。
To solve the problem about supporting mobility enhancing in named data network( NDN),this paper proposed a new mobility-aware prediction approach for content prefetching( MAP-CP) and an extended approach( extended MAP-CP,e MAP-CP) of mobile consumers in NDN for the city section mobility scenario. MAP-CP and e MAP-CP predicted the future access point( AP),then pre-fetched the data that could not be received under the current AP because of the handover process and cached them in the NDN node associated with the future predicted AP,and provided nearby service for the mobile consumers after the handover process,to reduce the average latency from the Interest packet issued to the requested Data packet received and improve the ratio of the number of Data packets received on the total number of Interest packets issued. Based on MAP-CP,e MAP-CP could improve performance further by pre-fetching the requested data during the handover process. The simulation experiment based on ndn SIM shows that MAP-CP and e MAP-CP have lower average latency and the higher ratio than original NDN,and e MAP-CP is better than MAP-CP. When the speed is 20 m / s and the traffic is 200 pps,the average latency in MAP-CP and e MAP-CP can be reduced by 4. 0% and 38. 7% respectively,and the ratio can be increased by 1. 2%and 4. 9% respectively.
出处
《计算机应用研究》
CSCD
北大核心
2016年第5期1441-1445,1460,共6页
Application Research of Computers
基金
国家"973"计划资助项目(2012CB315803)
国家"863"计划资助项目(2013AA013501)
中国科学院战略先导专项资助项目(XDA06010306)
国家自然科学基金青年基金资助项目(61303241)