Patent ID: 7698556

Claim:
A method for communicating a public key of a sender device to a receiver device, the method comprising: transmitting a plurality of messages from the sender device to the receiver device at a first predetermined rate, each message including a first message portion including the public key of the sender device and a message identifier, and a value representing a predetermined transformation of the first message portion; receiving at least a subset of the plurality of messages at the receiver device; verifying that the received messages are received at the receiver device at a rate that is equal to or less than a second predetermined rate, the verification being performed by the receiver device; verifying that each received message fulfils at least one predetermined criterion, the verification being performed by the received device; extracting a respective message identifier from each received message, the extraction being performed by the receiver device; transmitting the message identifiers extracted from the received messages from the receiver device to the sender device; and verifying that each of said transmitted message identifiers that are received at the sender device are message identifiers that were included in a message of the plurality of messages transmitted to the receiver device, the verification being performed by the sender device.