Methods and apparatuses for providing drm interoperability

A recording medium recording a command program which is executed and read by a digital processing device which performs a method of providing DRM interoperability in a proxy agent with respect to a plurality of digital rights management (DRM) service providers and a device which supports a predetermined DRM, comprising:

• at a first DRM service provider, a second DRM service provider, the proxy agent, and the device, identifying each other;
• and
• proxy re-encrypting an interoperable content (IC) provided from the first DRM service provider and providing the IC to the device,
• wherein the IC is second-level encrypted by using a key of the first DRM service provider, and
• proxy re-encryption is performed by using a proxy key generated from a proxy key information provided from the first DRM service provider and the second DRM service provider.

An apparatus of providing DRM interoperability with respect to a plurality of digital rights management (DRM) service providers and a device which supports a predetermined DRM, comprising:

• at least one processor which identifies a first DRM service provider, a second DRM service provider, and the device and is identified by the first DRM service provider, the second DRM service provider, and the device, proxy re-encrypts an interoperable content (IC) provided from the first DRM service provider and provides the IC to the device;
• and
• a memory connected with the processor to store the IC,
• wherein the IC is second-level encrypted by using a key of the first DRM service provider, and
• the processors performs the proxy re-encryption by using a proxy key generated from proxy key information provided from the first DRM service provider and the second DRM service provider.