KEY DISTRIBUTION METHOD, DEVICE AND SYSTEM

This application provides a key distribution method, an apparatus, and a system. The method includes: determining, by an identity management server based on AAA authentication information in an ID registration request message sent by a terminal, whether AAA authentication on the terminal succeeds; if the AAA authentication on the terminal succeeds, allocating an ID to the terminal and sending the ID of the terminal to a key management server; and generating, by the key management server, a private key of the terminal based on the ID of the terminal and returning the private key to the management server. After negotiating with the terminal to generate a first key, the identity management server encrypts the ID and the private key of the terminal by using the first key, and sends an encrypted ID and an encrypted private key to the terminal. After receiving the encrypted ID and the encrypted private key, the terminal obtains the ID and the private key of the terminal through decryption by using the first key. According to the key distribution method, apparatus, and system provided in this application, communication security performance of the terminal during ID-based registration authentication is improved.