Abstract: In view of a large amount of uncertain information within IP network and its effects upon Quality of Service（QoS） of multimedia traffic.In this paper，the reasons for production of uncertain information are discussed.A network model based on non-precision state is established.A new MPLS routing algorithm named Inaccurate Network State and Resource Balancing Algorithm（INSRBA） based on uncertain information to guarantee network QOS is proposed.This algorithm not only considers the uncertainty of the network state but introduces a thought of link load balance.Simulation results show that this algorithm performs better in network throughout and load balance.

Key words: inaccurate, degree of resource balance, availability probability

摘要： 考虑到IP网络中存在大量不确定信息及其对多媒体业务的QoS的影响，讨论了网络状态的不确定信息产生的原因，建立了非精确状态的网络模型，提出了一种MPLS的非精确状态路由算法INSRBA。算法在考虑非精确状态的同时引入了链路均衡度的思想。模拟结果证明算法在网络吞吐量和请求拒绝率方面达到了更好的性能。

关键词: 不精确, 资源均衡度, 可用概率