Patent ID: 8209533

Claim:
A method of authenticated key exchange in a data communication system, said method comprising: (a) a first communication device generating a first public value G A for use as a session public key and sending to a second communication device said first public value G A and a value x 2 that said first communication device wants receipt of confirmed by said second communication device; (b) said second communication device generating a second public value G B for use as another session public key, obtaining a shared key K, generating a value y 1 that said second communication device wants to have authenticated by said first communication device, generating a value y 2 that said second communication device wants receipt of confirmed by said first communication device, and computing a first keyed hash of said first public value G A , said second public value G B , said value x 2 , said value y 1 , and identification information of one of said first communication device and said second communication device, said first keyed hash using said shared key K; (c) said second communication device sending said first keyed hash, said second public value G B , said identification information of one of said first communication device and said second communication device, said value y 1 , and said value y 2 to said first communication device; (d) said first communication device obtaining said shared key K and computing a first verification keyed hash of said first public value G A , said second public value G B , said value x 2 , said value y 1 , and said identification information of one of said first communication device and said second communication device, said first verification keyed hash using said shared key K; and (e) said first communication device verifying that said first keyed hash equals said first verification keyed hash.