Publish/subscribe(pub/sub) paradigm is the main communication model for Information-Centric Network(ICN) proposals.A key issue for pub/sub system is how to route the content objects to the correct subscribers,and ICN is no exception.ICN network would be divided into core domain and many edge domains as today's internet does.HHR(Hierarchy Hybrid Routing scheme) is presented for ICN:A Chord-like routing scheme is used in core domain,while edge domains routing structure can be classified into three categories,Local Routing(LR),Delivery of Local Publication to Core domain(DLPC),and Remote Publication Routing into edge domain(RPR).LR can be decided by each edge domain,which determined by many factors,such as locality characteristic for pub/sub information and local policies.A hierarchical routing algorithm is proposed to solve DLPC and RPR simultaneously.Simulation results demonstrate that HHR can be fast deployed,and can be applied in large scale network or dynamic subscription environment.
To enhance user perceived performance,Akamai' s content distribution network(CDN) utilizes the domain name system(DNS) effectively to redirect users to close-by content replicas over short time scale.The use of DNS redirection has brought a significant advantage to Akamai' s CDN.However,the reliance on DNS also poses a fundamental threat to Akamai' s content distribution model.In particular,systematic evaluation and quantification illustrates the impact of recent emerging public DNS resolving services on Akamai' s CDN,including the degradation of corresponding user perceived performance and the benefit damnification of collaborating internet services providers(ISPs) that host Akamai's edge servers.The measurement demonstrates that a considerable penetration of public DNS resolving services(e.g.,OpenDNS and GoogleDNS) effectively corrupts the Akamai' s serving model,namely the large-scale server distribution and quick DNS redirection.
为了提供高质量的流媒体服务,内容发布网络(CDN)利用域名解析系统(DNS),将用户重定向到附近的内容服务器。近年来,域名解析系统的发展,尤其是基于IPAnycast的域名解析系统的兴起(例如,Google Public DNS,Open DNS),必将对CDN网络的内容发布机制造成影响。同Web、Email等其它Internet服务相比,流媒体服务对网络资源有较高的要求,DNS对其影响更加明显。本文首先阐明基于IPAnycast的域名解析系统对CDN网络内容发布模型的冲击,然后分析其影响流媒体服务质量的各种因素,最后通过实验来比较当使用不同域名解析服务时CDN网络承载的流媒体的服务质量。
针对如何为互联网用户从多个相同或相似的服务中进行选择的问题,提出了一种新的服务选择算法:基于Qo E(Quality of Experience)量化评估的服务选择算法(A Service Selecting Algorithm Based on Quantified Qo E Evaluation,ASSABQ).该算法基于一种层次化评分模型,从历史评分中学习获取用户偏好,根据多种评价因素计算每个可用服务的满意度,并选择满意度最高的服务给用户.与已知算法相比,ASSABQ算法的复杂度从O(n2)下降到O(n).仿真实验结果表明,在相同应用场景下,采用ASSABQ算法得到的用户满意度比已知算法提高约10%.
