Patent ID: 8321660
Filing Date: 2012-11-27
Classification: G11B,H04L,H04N

Abstract:
1. A method of reproducing an encrypted content in a device connected to a network, the method comprising: receiving the encrypted content to be reproduced; requesting a token for decrypting the received content from an external device containing a first partial key of the device via the network; receiving the requested token from the external device; and decrypting the received token by using a second partial key contained in the device, wherein if it is determined that the device has been revoked, receipt of the token fails, wherein a device key is divided to create the first partial key and the second partial key, wherein the requesting the token further comprises transmitting an identification (ID) of the device and the encrypted content, and wherein the token comprises a mediate decryption value of the transmitted encrypted content calculated based on the first partial key of the device corresponding to the transmitted ID.