Research And Implementation On The Defense Of DNS Hijacking In Ip Multimedia Subsystem

As IMS becomes the consensus of the Fixed-Mobile Convergence, current security problems in the Internet bring strong threats to IMS, while the open IP network architecture gives communication network convenient access and abundance of service. Behaving as the link of the network, the security of DNS directly determines that of the entire network, so it is crucial to protect the DNS in IMS.On the basis of former researcher's work on the defence of DNS hijacking and IMS security mechanism, this paper analyzes the secure architecure given by IMS and potential security problems in IMS, integrates disperse chaos model and the synchronization principal of chaos, and design a new proposal to defense against DNS Hijacking in IMS. The new proposal makes use of IMS AKA and inter-domain authentication keys to generate chaos encryption parameters, calculates the ID of DNS query reply and response packets by Henon two-dimension chaos system, and designs a serial number deposit table on the DNS server to store related chaos parameters of IMS clients and other DNS servers, in order to reduce the delay caused by the new proposal. The security of new proposal relies on the difficulty to break down the chosen chaos algorithm. The occupied memory space limits within the range of a common DNS server. Also the new proposal will not bring additional communication flows in the network, and will not bring new security problems to DNS.The new proposal is proofed to be effective to defense DNS Hijacking attacks with low delay by being coded with standard C language in Linux develop environment and deployed in the IMS test bed. The delay of the proposal is found to have optimization potential in the analysis of the test result.The successful implementation of the new proposal builds a test bed for the IMS research, and brings out new thoughts to solve other security problems in IMS.