Patent ID: 7574747

Claim:
A method for a computing device acting as a sink for rights-managed content to register with a computing device acting as a source for the content, the sink employing a port architecture comprising multiple ports, the source registering the sink only if the sink satisfies a proximity requirement, the method comprising: the sink sending a registration request to the source; the source validating the registration request; the source sending a registration response to the sink, the registration response including a first random value as a secret; the sink sending to the source, a port address of a first port of the sink, the first port selected for satisfying the proximity requirement based on speed of message communications between the source and the sink via the first port; the source sending a proximity message to the sink via the first port and concurrently noting a start time, the proximity message including a second random value selected as a nonce for one time use; the sink upon receiving the proximity message employing the secret and the nonce to generate a proximity value and sending a proximity response with the proximity value to the source; and the source receiving the proximity response with the proximity value from the sink via the first port and concurrently noting an end time, verifying the proximity value based on the secret and the nonce, calculating from the noted start and end times an elapsed time, comparing the elapsed time to a predetermined threshold value, deciding from the comparison whether the sink satisfies the proximity requirement, and registering the sink as being able to access content from such source if the sink satisfies the proximity requirement.