A novel key derivation method for eavesdropper in LTE system

The security mechanism of LTE system, which provides radio communication and its services with secure network, is much more perfect than that of 3G. This paper puts forward a novel method for key derivation based on the idea of combination of vulnerabilities in both radio interface and core-network in perspective of eavesdropper. The radio child-keys are produced according to the security algorithm list provided by plain radio message and parent-key obtained, and the right key is decided by comparing the plain context with the decrypted context. It is proved that the radio child-key is able to be obtained in this way according to the analysis of feasibility and complexity.