Using cache in the voice platform based on VoiceXML (Voice eXtensible Makeup Language) could reduce the cost of network bandwidth

server-load and delay of request.Through analyzing the cache model of voice platform

the Fitting Predicting algorithm is proposed.It estimates the validity of the cached document by performing parameter fits to stochastic distribution and predicting the change probability of VoiceXML documents within a certain period.Simulated research indicates the algorithm surpasses the Alex protocol and can obtain a stale ratio lower than 1/10000 to meet the demand of the voice platform while effectively enhancing the system performance.