Importance

Loading Importance Indicators...

Abstract

An arrangement of authenticating communications network users and means for carrying out the arrangement. A first challenge N1 is transmitted from a first user A to a second user B. In response to the first challenge, B transmits a first response and second challenge N2 to A. A verifies the first response. A then generates and transmits a second response to the second challenge to B, where the second response is verified. The first response must be of a minimum form f(S1, N1, . . . ), and the second response must be of the minimum form g(S2, N2, . . . ). S1 and S2 are shared secrets between A and B. f() and g() are selected such that the equation f'(s1,N1', . . . )=g(S2, N2) cannot be solved for N1' without knowledge of S1 and S2. f'() and N1' represent expressions on a second reference connection. Preferably, the function f() may include the direction D1 of the flow of the message containing f(), as in f(s1, N1, D1, . . . ). In such a case, f() is selected such that the equation f'(S,N1',D1', . . . )=f(S, N2, D1, . . . ) cannot be solved for N1' without knowledge of S1 and S2 and D1' is the flow direction indicator of the message containing f'() on the reference connection.

Loading the Abstract Image...

First Claim