Secure re-use of sim security parameters between different parties

Abstract

Various arrangements for using a subscriber identification module (SIM) card for authentication on a wireless network are detailed herein. A DKi (delta Ki) value can be stored by a SIM card. The SIM card can calculate a FKi (full Ki) value using the DKi value and a BKi value. The SIM card can be used to attach to the wireless network, wherein the SIM card is installed within a wireless device. The SIM card can receive a challenge from the wireless network. The SIM card can calculate an answer to the challenge using the FKi value. The answer can then be transmitted to the wireless network.

What is claimed is: 
     
         1 . A method for using a subscriber identification module (SIM) card for authentication on a wireless network, the method comprising:
 storing, by the SIM card, a DKi (delta Ki) value, wherein:
 the SIM card has an immutable BKi (base Ki) value; and 
 the DKi value is editable by a SIM card owner system; 
   calculating, by the SIM card, a FKi (full Ki) value using the DKi value and BKi value;   attaching, by the SIM card, to the wireless network, wherein the SIM card is installed within a wireless device;   receiving, by the SIM card, from the wireless network, a challenge;   calculating, by the SIM card, an answer to the challenge using the FKi value; and   transmitting the answer to the wireless network, wherein in response to the answer being correct, the wireless device having the SIM card installed is successfully authenticated to use the wireless network.   
     
     
         2 . The method for using the SIM card for authentication on the wireless network of  claim 1 , further comprising:
 calculating, by the SIM card owner system, the DKi value; and   providing, by the SIM card owner system, the DKi value to the SIM card.   
     
     
         3 . The method for using the SIM card for authentication on the wireless network of  claim 2 , further comprising:
 calculating, by the SIM card owner system, an FKi value based on the DKi value and the BKi value.   
     
     
         4 . The method for using the SIM card for authentication on the wireless network of  claim 3 , further comprising:
 providing, by the SIM card owner system, the FKi value to the wireless network.   
     
     
         5 . The method for using the SIM card for authentication on the wireless network of  claim 4 , wherein the challenge received from the wireless network is based on the FKi value. 
     
     
         6 . The method for using the SIM card for authentication on the wireless network of  claim 1 , wherein the SIM card owner system calculated the DKi value by subtracting the Bki value from a random number. 
     
     
         7 . The method for using the SIM card for authentication on the wireless network of  claim 2 , further comprising:
 manufacturing the SIM card such that the immutable BKi value is permanently stored and the DKi value is editable.   
     
     
         8 . The method for using the SIM card for authentication on the wireless network of  claim 1 , further comprising:
 storing, by the SIM card, a DOPc (delta operator code) value, wherein the SIM card has an immutable base OPc (BOPc) value;   calculating, by the SIM card, a FOPc (full operator code) value using the DOPc value and BOPc (base operator code) value;   calculating, by the SIM card, a network answer to a network challenge using the FOPc value;   receiving, by the SIM card, the network answer to the network challenge from the wireless network; and   determining, by the SIM card, the calculated network answer to the challenge and the received network answer to the network challenge match.   
     
     
         9 . The method for using the SIM card for authentication on the wireless network of  claim 8 , further comprising:
 calculating, by a SIM card owner system, the FOPc value based on the DOPc value and the BOPc value.   
     
     
         10 . The method for using the SIM card for authentication on the wireless network of  claim 9 , further comprising:
 providing, by the SIM card owner system, the FOPc value to the wireless network, wherein the wireless network uses the FOPc value to determine the answer to the challenge received from the SIM card.   
     
     
         11 . A system that uses a subscriber identification module (SIM) card for authentication on a wireless network, the system comprising:
 a SIM card, configured to:
 store an international mobile subscriber identity (IMSI); 
 output the IMSI for transmission to a wireless network; 
 store a BKi (base Ki) value that is immutable; 
 store a DKi (delta Ki) value that is editable; 
 calculate a FKi (full Ki) value using the DKi value and BKi value; 
 calculate a response to a challenge using the calculated FKI; and 
 output the response to the challenge for transmission to the wireless network. 
   
     
     
         12 . The system that uses the SIM card for authentication on the wireless network of  claim 11 , further comprising:
 a SIM card owner system in communication with the wireless network; and   a SIM card database that maps a plurality of IMSIs with a plurality of BKi values, wherein the IMSI is mapped to the BKi value.   
     
     
         13 . The system that uses the SIM card for authentication on the wireless network of  claim 12 , wherein the SIM card owner system is further configured to:
 compute the DKi value mapped to the IMSI and BKi value; and   compute the FKi value using the DKi value and the BKi value.   
     
     
         14 . The system that uses the SIM card for authentication on the wireless network of  claim 13 , wherein the SIM card owner system is further configured to transmit the DKi value to the SIM card. 
     
     
         15 . The system that uses the SIM card for authentication on the wireless network of  claim 14 , wherein the DKi value is transmitted to the SIM card via the wireless network. 
     
     
         16 . The system that uses the SIM card for authentication on the wireless network of  claim 14 , wherein the SIM card owner system is further configured to transmit the FKi value to the wireless network. 
     
     
         17 . The system that uses the SIM card for authentication on the wireless network of  claim 16 , wherein the wireless network creates the challenge based on the FKi value. 
     
     
         18 . The system that uses the SIM card for authentication on the wireless network of  claim 17 , wherein the SIM card owner system is configured to calculate the DKi value by subtracting the BKi value from a random number. 
     
     
         19 . The system that uses the SIM card for authentication on the wireless network of  claim 12 , wherein the SIM card is further configured to:
 store a BOPc (base operator code) value that is immutable;   store a DOPc value that is editable;   calculate a FOPc value using the DOPc value and the BOPc value;   calculate a network challenge using the FOPc;   calculate a calculated network answer to the challenge using the FOPc;   receive a network answer to the network challenge from the wireless network; and   determine that the received network answer matches the calculated network answer.   
     
     
         20 . The system that uses the SIM card for authentication on the wireless network of  claim 19 , wherein the SIM card owner system is further configured to store the DOPc value as mapped to the IMSI.