Method, apparatus and computer program for operating a user equipment

Abstract

Embodiments provide a method, apparatus and computer program for operating a user equipment (UE). The method beings by determining that a valid authentication for the UE, generated with a radio network operating with a first radio access technology (RAT), is not a mutual authentication between the UE and the network operating with the first RAT. In response, the UE unilaterally takes action to prevent the valid authentication that is not a mutual authentication from being used to authenticate with a radio network operating with a second RAT that utilizes mutual authentication.

1 . An electronic device comprising:
 circuitry configured to
 identify that an authentication for the electronic device generated with a first radio network operating according to a first radio access technology (RAT) is not a mutual authentication between the electronic device and the first network operating according to the first RAT; and 
 prevent the authentication from being used to authenticate with a second radio network operating according to a second RAT that utilizes mutual authentication. 
   
     
     
         2 . The electronic device of  claim 1 , wherein
 the circuitry is configured to prevent the authentication from being used to authenticate with the second radio network by including, in a tracking area update request sent to the second radio network operating according to the second RAT, an indication that the electronic device does not have a valid security context regardless of the authentication that is not a mutual authentication   
     
     
         3 . The electronic device of  claim 1 , wherein
 the circuitry is configured to prevent the authentication from being used to authenticate with the second radio network by deleting a security context associated with the authentication that is not a mutual authentication in a case that the electronic device moves to the second radio network operating according to the second RAT.   
     
     
         4 . The electronic device of  claim 3 , wherein
 the circuitry is configured to control performing a procedure to detach from the first radio network operating according to the first RAT in the case that the electronic device moves to the second radio network operating according to the second RAT.   
     
     
         5 . The electronic device of  claim 4 , wherein
 the circuitry is configured initiate a procedure to attach to the second radio network operating according to the second RAT by establishing a new security context with the second radio network operating according to the second RAT.   
     
     
         6 . The electronic device of  claim 1 , wherein
 the circuitry is configured to prevent the authentication from being used to authenticate with a second radio network by disabling a capability for the electronic device to perform an inter-RAT procedure with radio networks operating according to the second RAT.   
     
     
         7 . The electronic device of  claim 5 , wherein
 the circuitry is configured to utilize an authentication and key agreement (AKA) procedure to establish a new security context with an interim radio network operating with a third RAT after the disabling.   
     
     
         8 . The electronic device of  claim 7 , wherein
 the circuitry is configured to re-enable the capability of the electronic device to perform the inter-RAT procedure with radio networks operating with the second RAT upon establishing the new security context with the interim radio network.   
     
     
         9 . The electronic device of  claim 1 , wherein
 the circuitry is configured to determine that the authentication is not a mutual authentication by identifying that a ciphering key sequence number, included in a message that the electronic device sends to the second radio network operating according to the second RAT, is related to a security context used in the first RAT which does not represent a mutual authentication.   
     
     
         10 . The electronic device of  claim 9 , wherein
 the circuitry is configured to receive, from the second radio network operating according to the second RAT, a message indicating that a security context corresponding to the electronic device is mapped; and   prevent the authentication from being used to authenticate with the second radio network by sending a reject message to the second radio network operating with a second RAT.   
     
     
         11 . The electronic device of  claim 9 , wherein
 the circuitry is configured to receive, from the second radio network operating according to the second RAT, a message indicating that a security context corresponding to the electronic device is mapped; and   the circuitry is configured to prevent the authentication from being used to authenticate with the second radio network by ignoring the received message.   
     
     
         12 . The electronic device of  claim 1 , wherein
 the second RAT is Evolved Universal Terrestrial Access Radio Access (E-UTRA) and the first RAT is other than E-UTRA.   
     
     
         13 . An electronic device comprising:
 circuitry configured to
 identify that a valid authentication for the electronic device generated with a first radio network operating according to a first radio access technology (RAT) is not based on mutual authentication; and 
 inhibit the valid authentication from being used for authentication with a second radio network operating according to a second RAT that utilizes mutual authentication. 
   
     
     
         14 . The electronic device of  claim 13 , wherein
 a first radio network operates according to Global System for Mobile Communications (GSM) and the second radio network operates according to Evolved Universal Terrestrial Access Radio Access (E-UTRA).   
     
     
         15 . The electronic device of  claim 13 , wherein
 the circuitry is configured to inhibit the valid authentication from being used for authentication with a second radio network by transmitting a message to the second radio network indicating that the electronic device does not have a valid security context to access the second radio network.   
     
     
         16 . The electronic device of  claim 13 , wherein
 the circuitry is configured to delete the valid authentication in a case of performing handover from the first radio network to the second radio network.   
     
     
         17 . The electronic device of  claim 13 , wherein
 the circuitry is configured to inhibit the valid authentication from being used for authentication with a second radio network by preventing the electronic device from performing a handover from the first radio network to the second radio network.   
     
     
         18 . The electronic device of  claim 13 , wherein
 the circuitry is configured to inhibit the valid authentication from being used for authentication with a second radio network by preventing the electronic device accessing the second radio network.   
     
     
         19 . A method performed by an electronic device, the method comprising:
 performing mutual authentication with a first radio network operating according to a first radio access technology (RAT) to establish a valid authentication to access the first radio network;   detecting the existence of a second radio network operating according to a second RAT that utilizes mutual authentication; and   preventing the valid authentication from being used for authentication with the second radio network operating according to the second RAT that utilizes mutual authentication.   
     
     
         20 . The method of  claim 19 , further comprising:
 deleting the valid authentication in a case of performing handover from the first radio network to the second radio network.