Abstract: The contents protection providing method includes: creating an encrypted stream with encrypted data; creating a key stream including key information for decrypting the encrypted data; creating reference information for connecting the key information to the encrypted data corresponding to the key information; and transmitting the encrypted stream, key stream, and reference information to a terminal.

Abstract: Provided is a system for exchanging contents between a first DRM apparatus and a second DRM apparatus, wherein each of which belongs to different DRM domain. The first DRM apparatus includes unpackaging means for unpackaging first DRM formatted contents into clear resources, metadata, and rights expression; converting means for converting each of the clear resources, metadata, and rights expression into its own predefined neutral format, respectively; generating means for generating neutral formatted contents by combining the converted resources, metadata, and rights expression; adding predetermined header information thereto; and transmitting means for transmitting the neutral-formatted contents to said second DRM apparatus.

Abstract: Provided are a system renewability message providing method, a system renewability message using method and an apparatus thereof. The system renewability message providing method, includes: creating system renewability message container information including revocation list information for contents protection; and defining the system renewability message container information as an International Organization for Standardization (ISO) base media file format and distributing the system renewability message container information to a terminal.

Abstract: Provided is a contents protection providing method, a protected contents consuming method and an apparatus thereof. The contents protection providing method includes: creating protected scheme information; and transmitting the protected scheme information to a terminal, wherein the protected scheme information includes: scheme type information including identification (ID) information of a protection scheme; and scheme information including detailed information of the protection scheme.

Abstract: An electronic cash system for performing an electronic transaction using an electronic cash, comprises at least one user apparatus each capable of using the electronic cash; an authentication center apparatus, for receiving a user identity information, a corresponding public key along with a certificate issue request from one of the user apparatus and for issuing a certificate for the user apparatus's public key after confirming the identity of the corresponding user; at least one shop apparatus for confirming the identification of the user based on the user apparatus's public key, the corresponding certificate, for producing a challenge value unique to respective transaction using an electronic cash received from the user apparatus and then for confirming the validity of the electronic cash based on a response value from the user apparatus in response to the challenge value, so as to perform an electronic cash transaction with the user apparatus; and at least one bank apparatus for opening an anony