Patent ID: 8325918

Claim:
A client terminal connected to a streaming server, the client terminal comprising: a central processing unit; a receiving unit for receiving packets from the streaming server, wherein the streaming server transmits the packets of stream data based on packeting control information, wherein the packeting control information and header information are added to the stream data after encryption of the stream data, wherein the stream data is generated based on compression-encoding of at least one of image data and audio data, wherein the encryption of the stream data comprises encrypting every predetermined unit of the stream data from a leading portion of the predetermined unit based on an encryption block size smaller than a packet size, and wherein remainder data of the stream data is not encrypted when a size of the remainder data is smaller than the encryption block size; an inverse-packeting unit for inverse-packeting the packets for the stream data; a decrypting unit for decrypting encrypted portion of the stream data; and a decoding unit for decoding the stream data into the at least one of image data and audio data.