| 摘要 |
This invention generally relates to secure communications links for data transmission and more particularly relates to data communications links in which asymmetric cryptographic techniques are used to establish a secure link using symmetric cryptography. Applications include download of software etc. to a mobile terminal. A method of establishing a secure communications link between a mobile terminal and a server, of a mobile communications system, one of the terminal and server being an originator and the other a recipient, the method comprising: sending a first message from the originator to the recipient, the first message comprising; an identify certificate for the originator, the certificate including a public key for the originator, first data block, and a signature of the originator generated by operating on the first data block, the first data block comprising at least an identifier for the recipient and a secret number encrypted using a public key of the recipient; and authenticating the first message at the recipient using the recipient identifier. |
