METHOD AND APPARATUS FOR ENCRYPTING TRANSPORT STREAM OF MULTIMEDIA CONTENT, AND METHOD AND APPARATUS FOR DECRYPTING TRANSPORT STREAM OF MULTIMEDIA CONTENT

摘要

A method of transporting an encrypted stream of multimedia content is provided. In the method, when a packet contains data of a predetermined length including selected data from pieces of data corresponding to the multimedia content and a header, key information, and first time information from among pieces of information included in a selected packet from among at least one packet are received, and encryption information is determined from the key information and the first time information, according to a key derivation function. The first time information is variable with time. The at least one packet including data corresponding to the multimedia content is encrypted using the encryption information. The at least one encrypted packet and the key information are transported.