Method and apparatus for generating new key

PROBLEM TO BE SOLVED: To provide a method for generating a new key, which improves forward security in key generation in a handover in long term evolution (LTE). SOLUTION: The method includes the steps of: generating, at a certain source base station, a first temporary key K_eNB* based on a key K_eNB which is used to protect the communication between a mobile terminal UE and the source base station; forwarding the K_eNB* to a key generation unit for generating a second temporary key K_eNB*+, based on the K_eNM* and further based on a secret key shared with the mobile terminal; and forwarding the K_ENB*+ to a target base station and generating the new key K_eNB based on the K_ENB*+. The mobile terminal generates the first temporary key K_eNB* based on the key K_eNB which is used with the source base station, generates the second temporary key K_eNB*+ based on the K_eNB* and further based on a secret key shared by the key generation unit and the mobile terminal, and generates the new key K_eNB based on the K_eNB*+. COPYRIGHT: (C)2010,JPO&INPIT