Research Of Access Security Mechanism In UMTS System

The security of the third generation mobile system is built on the basis of the security of the second generation mobile system,by adoping the secure characteristic that have been proved essential and strengthened of the GSM ,and rectifing the disadvantage of the second generation mobile system.The author has done lots of research on the access network and core network according to the security protocol of 3GPP,and has rerearched the performance of security for user access security mechanism in UMTS system appling the flow analysis,and has designed some projects to improve the weakness of security mechanism related to the Security flaws by designing the flow detailedly and the key technology related to the flow.Finally,research and analyze the security context and security mechanism when coexistence of the GSM and UMTS system is appeared in the process of second generation mobile system to the third generation mobile system.The author has mainly researched on the architecture,security principles, security objectives,security architecture, access security mechanism and security features in the handover between UMTS and GSM system as follows:(1) research the security principles and security objectives of the UMTS system.By analysis of the weakness of GSM system,get the result that the improvement on the access security mechanism and existence of possible security threats in UMTS system.Meanwile,research the security architecture according to the logistic and functional architecture,then summarize the security feature of the UMTS system.(2) research the access security mechanism of the UMTS system,maily research the function , achieved security objectives and implementation process of the user identity identification, authenctication and key agreement, local authentication in idlesse, local authentication in connection.Then a detailed analysis of the standardized f8 and f9 is given,at the same time two algorithms are realized according to the kernel algorithm KASUMI.(3) analyze the access security mechanism of the UMTS system,get the result that the weakness on the security,then design the improvement methods on the process that which is used to authenticate network by terminal,the process that which is used to authenticate terminal by network in idlesse or connection. The author mainly designed the principles, detailed implementation process and key technology related to implementation process.(4) research the security feature when UMTS and GSM systems handovered each other,mainly analyze the change of security context between the USIM or SIM, the transmission rule of the authentication vectors between the VLR/SGSN, the change of security context between the UTRAN and GSM BSS.Finally,research the security feature and give the different security context in different environment.