Digital cable broadcasting receiver including security module and method for authenticating the same

A digital cable broadcasting receiver including a security module and a method for authenticating the same are provided to only a subscriber who joins a normal broadcasting service to watch a broadcast program, consequently preventing the illegal watching of a broadcast program. A digital cable broadcasting receiver module(100) extracts transport stream data from a broadcasting signal received from a head-end system through the authentication process with a digital broadcast head end system(300). A separable conditional access module(200) which is inserted into the digital cable broadcast receiver module transmits descrambled transport stream data to a digital cable broadcast reliever module by descrambling the transport stream data received from the head end system. A separable and conditional receiving module which is a cable card of POD(Point Of Deployment) method realizes the bidirectional communication with the digital cable broadcast transceiver module through the conditional receiving module interface(180) of the digital cable broadcast receiver module.