the present invention provides a method for authenticating the copy right of a device by an offline way , a digital right protection system , and a method for providing digital contents , which mainly includes embedding an authentication agent into the digital content , said authentication agent , instead of the copyright issuer at the server side , authenticates the rendering qualification of the device before rendering the digital content . if the device is a non - compliant device , the authentication agent will not permit the device to render the digital content . the technique of the invention realizes offline digital right management , so it is not restricted by the network condition and can be applied widely in various environments .