×

Method of authentication with improved security for secrecy of authentication key

  • US 5,377,267 A
  • Filed: 08/16/1993
  • Issued: 12/27/1994
  • Est. Priority Date: 08/19/1992
  • Status: Expired due to Fees
First Claim
Patent Images

1. A method of authentication for a mobile subscriber to receive a roaming service by moving from a first communication network owned by a first service provider to a second communication network owned by a second service provider, comprising the steps of:

  • (a) transmitting a mobile station identifier uniquely assigned to the mobile subscriber by the first service provider, from the mobile subscriber to the second communication network, when the mobile subscriber moved from the first communication network to the second communication network;

    (b) transmitting the mobile station identifier transmitted at the step (a) along with an authentication data indicative of a tentative authentication key to be used only in an authentication at the second communication network, from the second communication network to the first communication network;

    (c) transmitting an enciphered authentication data obtained at the first communication network by enciphering the authentication data transmitted at the step (b) by using a permanent authentication key shared by the first communication network and the mobile subscriber, from the first communication network to the mobile subscriber via the second communication network;

    (d) deciphering the enciphered authentication data transmitted at the step (c) by using the permanent authentication key to obtain the tentative authentication key at the mobile subscriber; and

    (e) carrying out the authentication at the second communication network by using the tentative authentication key obtained at the step (d) on the mobie subscriber side.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×