Abstract: A method of mutual authentication between a server and a plurality of clients, including: (a) generating, by a client, a first client random number and a first client one time ID based on first and second values; (b) sending the first client one time ID and an encrypted version of the first client random number to the server by the client; (c) generating, by the server, a first server random number and a first server ID based on the first client random number and the first value; (d) sending, by the server, the first server one time ID and an encrypted version of the first server random number to the client by the server; (e) generating, by the client, a second client random number and a second client one time ID based on said first server and first client random numbers; (f) sending, by the client, the second client one time ID and an encrypted version of the second client random number to the server by the client; (g) generating, by the server, a second server random number and a second server one time ID b