Patent ID: 8312166

Claim:
A method of determining a proximity between a root node and a leaf node in a network, the method comprising the steps of: computing a link proximity value between any two mutually connected nodes in the network, the link proximity value being computed at predetermined time intervals; at an initial node, being one of the root node and the leaf node, sending a proximity computation request message containing a proximity counter and a random challenge number to an intermediate node to which said initial node is connected, the proximity computation request message being encrypted, and the random challenge number being included for purposes of authentication; at an intermediate node being connected to a first node and to a second node, upon receipt of the proximity computation request message containing a proximity counter from the first node, adding the computed link proximity value to the proximity counter and passing on the proximity computation request message to the second node; and at a final node, being the other of the root node and the leaf node, upon receipt of the proximity computation request message, determining the proximity between the root node and the leaf node as the value indicated by the proximity counter.