Patent ID: 7237111

Claim:
A method of authenticating a channel authorization using a NAD (Network Access Device) in a combined broadcasting and communication system having a plurality of STBs (Set Top Boxes) for receiving a broadcasting, an OLT (Optical Line Terminal)/ONU (Optical Network Unit) for transferring a broadcasting stream to the STBs, and an AAA (Authentication, Authorization and Accounting) server for a channel authentication, the method comprising: a first step of providing the NAD in the ONU to determine whether to switch the broadcasting stream to the STBs; a second step of initializing the NAD by receiving and storing authentication information of the channel authorization from the AAA server; a third step of the NAD performing an authentication using the stored authentication information in response to a channel request from the STB and switching to the requested channel after the authentication; and a fourth step of changing and storing the authentication information of the channel authorization in response to an update signal from the AAA server.