Method and system for securing wireless communications

Abstract

A method for transmitting an encrypted signal to a wireless transmit/receive unit (WTRU) such that decryption of the encrypted signal depends on a trust zone associated with the WTRU is disclosed. The encryption may be performed using hierarchical modulation, scrambling, authentication, location validation, or a combination thereof. The size of a trust zone may also be adjusted.

What is claimed is: 
     
         1 . A method for use in a wireless transmit/receive unit (WTRU) comprising:
 receiving, by the WTRU, an encrypted signal; and   decrypting, by the WTRU, the encrypted signal on a condition that the WTRU is associated with one of a plurality of trust zones and not associated with a no-trust zone, wherein the decrypting is performed with a different level of information depending on the trust zone with which the WTRU is associated.   
     
     
         2 . The method of  claim 1 , wherein the zones are geographic zones. 
     
     
         3 . The method of  claim 1 , wherein:
 the decrypting the encrypted signal includes:
 demodulating an encrypted message using a first modulation level of a hierarchical modulation point selected from a hierarchical modulation constellation; 
 demodulating an encryption code using a second modulation level of the hierarchical modulation point; and 
 decrypting the encrypted message using the encryption code; and 
   the second modulation level cannot be detected in the no-trust zone.   
     
     
         4 . The method of  claim 1 , wherein the decrypting the encrypted signal includes descrambling a symbol in the message using a scrambling sequence. 
     
     
         5 . The method of  claim 4 , wherein the decrypting the encrypted signal includes receiving, by the WTRU, a portion of the scrambling sequence. 
     
     
         6 . The method of  claim 5 , wherein a first trust zone includes a second trust zone and a third trust zone and the receiving a portion of the scrambling sequence includes:
 receiving, by the WTRU, a first portion of the scrambling sequence on a condition that the WTRU is associated with the second trust zone; and   receiving, by the WTRU, a second portion of the scrambling sequence on a condition that the WTRU is associated with the third trust zone.   
     
     
         7 . The method of  claim 4 , further comprising:
 providing, by the WTRU, authentication information including information concerning authentication of a location of the WTRU; and   receiving, by the WTRU, the level of information for decrypting the encrypted signal.   
     
     
         8 . The method of  claim 7 , wherein a first trust zone includes a second trust zone and a third trust zone and the providing authentication information includes:
 providing a first set of authentication information on a condition that the WTRU is associated with the second trust zone; and   providing a second set of authentication information on a condition that the WTRU is associated with the third trust zone.   
     
     
         9 . The method of  claim 1 , further comprising:
 providing information to validate a location of the WTRU.   
     
     
         10 . The method of  claim 9 , wherein the providing information to validate a location of the WTRU includes:
 receiving, by the WTRU, a first location verification message; and   transmitting, by the WTRU, a first response, wherein the first response indicates whether the WTRU decoded the first location verification message.   
     
     
         11 . The method of  claim 10 , wherein providing information to validate a location of the WTRU includes:
 receiving, by the WTRU, a second location verification message; and   transmitting, by the WTRU, a second response, wherein the second response indicates whether the WTRU decoded the second location verification message.   
     
     
         12 . The method of  claim 1 , wherein the receiving an encrypted signal includes receiving a first part of a message. 
     
     
         13 . The method of  claim 12 , further comprising recovering the message by concatenating the first part of the message with a second part of the message. 
     
     
         14 . The method of  claim 12 , wherein the message is a scrambled message and further comprising recovering the message by concatenating the first part of the message with a second part of the message and descrambling the concatenated first and second parts of the message. 
     
     
         15 . The method of  claim 12 , further comprising recovering the message by applying an exclusive-or function to the first part of the message and a second part of the message. 
     
     
         16 . A wireless transmit/receive unit (WTRU) comprising:
 circuitry configured to receive an encrypted signal; and   the circuitry is further configured to decrypt the encrypted signal on a condition that the WTRU is associated with one of a plurality of trust zones and not associated with a no-trust zone, wherein the decrypting is performed with a different level of information depending on the trust zone with which the WTRU is associated.   
     
     
         17 . The WTRU of  claim 16 , wherein the zones are geographic zones. 
     
     
         18 . The WTRU of  claim 16 , wherein:
 to decrypt the encrypted signal includes:
 demodulating an encrypted message using a first modulation level of a hierarchical modulation point selected from a hierarchical modulation constellation; 
 demodulating an encryption code using a second modulation level of the hierarchical modulation point; and 
 decrypting the encrypted message using the encryption code; and 
   the second modulation level cannot be detected in the no-trust zone.   
     
     
         19 . The WTRU of  claim 16 , wherein to decrypt the encrypted signal includes descrambling a symbol in the message using a scrambling sequence. 
     
     
         20 . The WTRU of  claim 19 , wherein to decrypt the encrypted signal includes receiving, by the WTRU, a portion of the scrambling sequence.