Device and method for decrypting NAS (Network Attached Storage) signaling in LTE (Long Term Evolution) protocol monitoring analysis

The invention provides a device for decrypting an NAS (Network Attached Storage) signaling in LTE (Long Term Evolution) protocol monitoring analysis. The device comprises three parts: an NAS message decrypting parameter extracting module, an NAS message decrypting parameter storage maintaining module and an NAS message decrypting executing module. According to the technical scheme of the invention, the information related to UE (User equipment) safety is extracted from specific information on a S1-MME, S10 or S6a interface and is used for establishing, educing and maintaining the related parameters, such as a key, and the like, needed for decrypting the NAS information. Under the conditions of being free from changing the related configuration of an LTE network and configuring the data related to UE decryption for an LTE network protocol monitoring analysis system in advance, an operation of the protocol monitoring analysis system for decrypting the captured encrypted NAS information can be realized.