Method for Providing Information Security for Wireless Transmissions

Abstract

A wireless communication system includes a pager or similar device that communicates to a home terminal. The home terminal confirms the identity of the pager and attaches a certificate to the message for ongoing transmission. Where the recipient is also a pager, an associated home terminal verifies the transmission and forwards it in a trusted manner without the certificate to the recipient.

1 . A method of communicating a message between correspondents in a communication system through an intermediary terminal, said intermediary terminal sharing an identifier with one of said correspondents, and said intermediary terminal having access to said identifier and an associated certificate of a public key of said one of said correspondents, the method comprising:
 said one of said correspondents computing a secure communication including said message,   said one of said correspondents computing a signature component including a derivation of said secure communication and said identifier,   said one of said correspondents forwarding said signature component and said secure communication to said intermediary terminal,   said intermediary terminal verifying said signature component,   said intermediary terminal attaching to said secure communication said certificate of the public key of said one of said correspondents, and   said intermediary terminal forwarding said secure communication and said certificate to another of said correspondents.   
     
     
         2 . The method according to  claim 1  wherein said signature component includes a nonce unique to each communication. 
     
     
         3 . The method according to  claim 1  wherein said secure communication includes said message signed by said one of said correspondents. 
     
     
         4 . The method according to  claim 1  wherein said secure communication includes ciphertext encrypted with a public key of said another of said correspondents. 
     
     
         5 . The method according to  claim 1  wherein said intermediary terminal recovers said identifier from said signature component and retrieves said certificate based on said identifier. 
     
     
         6 . The method according to  claim 1  wherein said another of said correspondents is a recipient terminal, which utilizes said certificate to determine the public key of said one of said correspondents. 
     
     
         7 . The method according to  claim 6  wherein said recipient terminal signs another message including said public key of said one of said correspondents to generate a signature of said another message, and forwards said secure communication and said signature of said another message to a second of said correspondents. 
     
     
         8 . The method according to  claim 7  wherein said second of said correspondents retrieves said public key of said one of said correspondents using said signature of said another message, and extracts said message from said secure communication. 
     
     
         9 . The method according to  claim 1  wherein prior to said one of said correspondents computing a secure communication including said message, said one of said correspondents registers with said intermediary terminal by performing operations including: said intermediary terminal transferring a public key of said intermediary terminal to said one of said correspondents and said one of said correspondents transferring said public key of said one of said correspondents to said intermediary terminal. 
     
     
         10 . The method according to  claim 9  wherein said one of said correspondents has stored in memory a public key of a trusted party and said intermediary terminal has a certificate of said public key of said intermediary terminal signed by said trusted party, and wherein said one of said correspondents verifies said public key of said intermediary terminal with said public key of said trusted party. 
     
     
         11 . The method according to  claim 10  wherein said public key of said intermediary terminal is used by said one of said correspondents to sign said public key of said one of said correspondents for secure transfer to said intermediary terminal. 
     
     
         12 . The method according to  claim 10  wherein said one of said correspondents forwards authorization information to said intermediary terminal during registration and said intermediary terminal verifies that said one of said correspondents is not prior registered with a certifying authority. 
     
     
         13 . The method according to  claim 12  wherein said authorization information includes an address particular to said one of said correspondents for identification by said certifying authority. 
     
     
         14 . The method according to  claim 11  wherein said identifier is transferred from said intermediary terminal to said one correspondent upon verification by a certifying authority. 
     
     
         15 . The method according to  claim 14  wherein transfer of said identifier is secured by the public key of said one of said correspondents and said private key of said intermediary terminal. 
     
     
         16 . A system for communicating a message between correspondents, the system including an intermediary terminal, said intermediary terminal sharing an identifier with one of said correspondents, and said intermediary terminal having access to said identifier and an associated certificate of a public key of said one of said correspondents, said intermediary terminal and said correspondents being configured to perform operations comprising:
 said one of said correspondents computing a secure communication including said message;   said one of said correspondents computing a signature component including a derivation of said secure communication and said identifier;   said one of said correspondents forwarding said signature component and said secure communication to said intermediary terminal;   said intermediary terminal verifying said signature component;   said intermediary terminal attaching to said secure communication said certificate of the public key of said one of said correspondents; and   said intermediary terminal forwarding said secure communication and said certificate to another of said correspondents.   
     
     
         17 . The system according to  claim 16  wherein said signature component includes a nonce unique to each communication. 
     
     
         18 . The system according to  claim 16  wherein said secure communication includes said message signed by said one of said correspondents. 
     
     
         19 . The system according to  claim 16  wherein said secure communication includes ciphertext encrypted with a public key of said another of said correspondents. 
     
     
         20 . The system according to  claim 16  wherein said intermediary terminal is configured to recover said identifier from said signature component and retrieve said certificate based on said identifier. 
     
     
         21 . The system according to  claim 16  wherein said another of said correspondents is a recipient terminal, which utilizes said certificate to determine the public key of said one of said correspondents. 
     
     
         22 . The system according to  claim 21  wherein said recipient terminal is configured to sign another message including said public key of said one of said correspondents to generate a signature of said another message, and forward said secure communication and said signature of said another message to a second of said correspondents. 
     
     
         23 . The system according to  claim 22  wherein a second of said correspondents is configured to retrieve said public key of said one of said correspondents using said signature of said another message, and extract said message from said secure communication. 
     
     
         24 . The system according to  claim 16  wherein prior to said one of said correspondents computing a secure communication including said message, said one of said correspondents is configured to register with said intermediary terminal by performing operations including: said intermediary terminal transferring a public key of said intermediary terminal to said one of said correspondents and said one of said correspondents transferring said public key of said one of said correspondents to said intermediary terminal.