网络拓扑与容量的关系初探

Discussion about Network Capability Relevant to Topology Information of Network

网络服务质量(QoS)是现在计算机网络科学中被广泛关注的热点,大多数基于视频媒体服务的Internet业务都提出了服务质量的要求。不同于已有的基于局部网络拓扑信息的优化方法,文章以Watts等人提出的小世界(SmallWorld)网络作为网络拓扑模型,讨论如何利用全局拓扑信息进行网络资源和性能的优化。以一类小世界网络为例,讨论了捷径(捷径)路径对于网络拓扑容量的影响。经过理论的分析和仿真的实验表明:通过适当的增加捷径路径,可以提高网络的拓扑容量,进而使用户得到更好的网络服务。其中作为例子,该文给出了环形网络和具有规则捷径路径的网络拓扑容量的显示表达式。以小世界网络为研究对象的优点在于小世界网络具有简单性和普遍性,基于此类网络的拓扑容量分析为进一步研究复杂网络的网络拓扑容量问题提供了一条新的途径。

QoS on IP network is now becoming a hot topic in the field of computer science;most of multimedia appli-cations,such as interactive games and videoconference,request network can provide QoS-guaranteed services.This paper tries to calculate the capability of a set of Small World network,which is proposed by D.J.Watts and S.H.Strogatz in1998,relevant to shortcut routes.Theoretical analysis and simulation data show that adding properly shortcuts can result in improvement of transporting capability,that is,users of network can get much bandwidth and smaller delay.For in-stance,this paper has derived the explicit relationship of capability of a serial of Small World network with bandwidth of links and the number of nodes.The advantage of discussing transporting capability based on Small World network model is that Small World network is one of most popular model in the world at present ,and its structure network is so simple that calculation of transporting capability can be quantified,therefore provides a promising way to analyze the network capacity in a network environment.