【摘要】 在设计和实现新的路由协议之前,确定一个完善的特性集合具有十分重要的意义。文章认为这个集合还应包含一个新的重要元素:IP路径的对称性和可传递性。实验研究表明,在Internet网络目前的路由机制下,IP逻辑连接具有相当程度的连通不完全(不对称和不可传递)的病态特征,并且随着AS的网络规模的增加而显著增长。同时指出引入域的划分和独立管理的概念、把ISP的利益简单地建立在对底层网络的连通性的争夺上,这样的路由体系很难避免出现这种病态特征。更多还原

【Abstract】 What is the complete attribute set of routing infrastructure is decisive before implementing new routing protocol.Having surveyed the attribute set of routing protocol concerned at present,the paper adds a new fatal attribute,symmetry and transfer,to the set mentioned above.The experiment data shows clearly that,with the policy routing mechanism of present Internet,the monbid character of IP incomplete connectivity has reached to a quite degree,in other words,it is much asymmetric and non-transferable.Furthermore,this irrational situation becomes worse remarkably with enlarged scale of Internet.It also points out that this is hard to get rid of,due to introducing ideal of AS and independent management,as well as establishing the benefit of ISP simply on competitive IP connectivity.更多还原