The Implementation Of The Monitoring And Analysis System For VoIP

VoIP,based on IP protocol,is a voice transport technology.It has developed rapidly with the development of Internet.In 1995,Isreal's Vocal Tec company produced the InternetPhone,and after 10 years development,VoIP technology has made great progresses.As a new kind of voice communication technology,VoIP has impacted domestic traditional telecom operators extremely because of it's low costs and low prices,and in recent years,the telecom operators' revenue of Long-Distance Telephone has descended rapidly.Besides,the national supervision department faced new chanlleges about VoIP. Based on the requierment of national safly,new methods are needed to monitor the VoIP systems.But effective monitoring methods for VoIP are lacked now in China.And the telecom operators also need monitoring and analysis methods for VoIP urgently.Currently,there are two leading technology standards about VoIP,H.323 of ITU-T and SIP of IETE This thesis analyzes the two protocols,summarizes the characters of it's variation,gives a method to find the variant protocols through the BM fast-search-algorithm.Through a kind of fast HASH algorithm,RTP data stream cam be recognized from the Concurrent IP data streams.Based on CNC QingDao company's IP Metropolitan Area Networks,in this thesis,we analyze and design a monitoring and analysis system capable of monitoring IP broadband networks,through pattern filtering,signal analysing and rebuilding,stream rebuilding and replaying,and statistical functions.VoIP business on gigabit-Broa(?)band IP networks or trunks with even higher capacity can be analysed by this system.And it provide many functions for telecom operators,such as voice traffic monitor and analysis, block illicit voice traffic,voice traffic statistic,trend analysis.The system was tested by telecom operators successfully and could meet the demand of monitoring VoIP business.