Patent ID: 7551914
Filing Date: 2009-06-23
Classification: H04L,H04W

Abstract:
1. A method of authenticating a mobile node to a communication system, the communication system comprising a plurality of access nodes between which the mobile node is able to roam, the method comprising: (a) generating a numerical chain comprising a series of values using a one-way coding function such that a given value within the chain is easily obtainable from a subsequent value, but the subsequent value is not easily obtainable from that given value; (b) each time that the mobile node seeks to authenticate itself to an access node, sending a value from the numerical chain from the mobile node to an access node to which the mobile node wishes to attach, the sent value succeeding values in the chain already sent to access nodes; and (c) using the sent value at the access node to authenticate the mobile node on the basis of a value of the numerical chain preceding the sent value in the chain, the method further comprising, after each successful authentication, informing each of said plurality of access nodes that an authentication has been completed.