disclosed is a compatible system of digital rights management which enables the reproduction of the same contents between apparatuses each employing a different digital rights management system . the compatible system of digital rights management comprises : a user server including a first authentication document of a first apparatus ; a second apparatus connected to the first apparatus and outputting a contents request signal and a second authentication document to reproduce substantially the same contents ; and a provider server forming a virtual safe channel with the user server based on the contents request signal to receive the first authentication document , and generating first and second licenses encrypted through the first and second authentication documents to transmit the same to the second apparatus .