Patent ID: 7328342

Claim:
A method for secure transmission of information between a first and a second module, each module comprising one of the keys of a first pair of keys and one of the keys of a second pair of keys, the method comprising: generating a first random number and a second random number in the first module; generating a third random number in the second module; checking that one of the first, second, and third random numbers encrypted by one of the modules, then decrypted by the other of the modules, then re-transmitted re-encrypted to the one of the modules, is, after decryption in the one of the modules, identical to the one of the first, second, and third random numbers; and creating independently in each of the modules a common session key with at least three same numbers generated randomly partially in one module and partially in the other module, and transmitted as encrypted data between the two modules so that the two modules contain the at least three numbers; transmitting the certificate from the second module to the first module; verifying, in the first module, the signature of the certificate with a public certification key of the first module; and extracting a public key of the certificate, wherein the extracted public key and a private key of the first module form the first pair of keys, wherein information transmitted between the two modules is encrypted with the common session key.