Patent ID: 8156337

Claim:
A method for securing communication over a network medium between at least two devices including a first device and a second device, comprising: receiving over a location limited communication channel, by the second device, public authentication information transmitted by said first device, wherein the location limited communication channel has physical limitations which allow the second device to identify the first device communicating across the channel based on the limited locations accessible to the location-limited channel, thereby causing said location limited communication channel to be difficult to actively attack without detection, and wherein said public authentication information comprises a commitment to secret information; receiving a communication from said first device over said network medium, the communication comprising the secret information; authenticating said communication at said second device by determining that the commitment corresponds to the received secret information, thereby authenticating that said first device actually possesses said secret information; and in response to authenticating the communication at the second device, sending a communication over the network medium to the first device, the communication comprising a commitment to new secret information that will be used to authenticate a subsequent message from the second device.