Contents protection providing method and protected contents consuming method and apparatus thereof

A contents protection providing method, and the protected contents consuming method and an apparatus thereof are provided to prevent illegally copying the digital contents and to prevent effectively prevent from massively circulating the digital contents. An encoding stream including encrypted data which an encryption stream generating unit(203) is produced, and a key stream including the key information which the key stream generating unit(205) decodes encrypted data are produced. A reference information generating unit(207) produces encrypted data corresponding to the key information and the reference information for connecting the key information. The key management information including the access authority information which the key management information generator(209) can approach the key information is produced, and the transmit unit(211) transmits the encoding stream, the key stream, and the reference information and key management information in the terminal(213).