The Research And Implementation Of Security Technology Of 4G Private Mobile Radio Communications Based On Open Air Interface

Security technology in mobile communications,especially International Mobile Subscriber Identification Number(IMSI)direction,is different from the market common security technology,such as video surveillance,burglar alarm,smoke alarm,and it is innovative technology used to monitor someone's whereabouts or monitor human traffic of a region for special departments and special units.At present,security equipment of mobile communication in catching IMSI are mainly de for signed Global System for Mobile Communications(GSM)network,while on the one hand GSM network users are accelerating the loss,on the other hand GSM security equipment does not apply to 4G network,which gave birth to 4G network access IMSI security equipment needs.Therefore,this thesis will focus on researching and implementation on two aspects of wireless access and LTE protocol signaling to launch on catching IMSI technology under the 4G network.In the first place,the feasibility of IMSI acquisition under Long Term Evolution(LTE)network is studied and analyzed.First,do a focused study on the LTE network architecture and security mechanisms,and select Identification Procedure as a breakthrough to obtain IMSI before the mutual authentication.Second,in order to ensure that Identification Procedure can proceed smoothly,this thesis also discusses the contents of cell selection and cell reselection,mechanism of Radio Resource Control(RRC)connection,Identification Procedure signaling content and the call mechanism.The purpose is to obtain the user's IMSI through Identification Procedure.Third,according to the research contents,there are three important problems,which are wireless access problem,RRC connection problem and Identification Procedure signaling design and call problem,to be solved.In the second place,the OAI platform is an open source LTE software radio platform,which can be modified according to the needs,and this thesis achieves technology of getting IMSI under the 4G network through the platform.Aiming at the problems of wireless access problem,RRC connection problem and Identification Procedure signaling design and call problem,this thesis solves these through engineering methods.Eventually,Identification Procedure is implemented in the two signaling processes of Tracking Area Update and Attach,thus the thesis implements two scenarios for obtaining IMSI.Finally,this thesis completes the wireless access and signaling process testing,verify the feasibility of obtaining IMSI technology under 4G network.The results of the wireless access test show that the public network terminal can carry on the normal cell reselection to the private network which is set up in this thesis,and the test of the signaling flow shows the validity of the two kinds of IMSI signaling schemes mentioned in this thesis.The acquisition of IMSI technology is of great significance to the development of such security equipment,and it also provides reference for the design of future safety technology in mobile communication systems.