Patent ID: 8762726

Claim:
A method, performed by an authorization server, of securing access between a client having temporary connection to a computer via an access controller, said access controller for selectively passing instructions received from said client to said computer if a verification protocol utilizing a set of keys is met, said method comprising: receiving a request from said access controller for an updated first key; authenticating said request; determining said updated first key and a second key corresponding to said updated first key; delivering said updated first key to said access controller; and wherein said verification protocol includes a generation of a random number by said client, an encryption of said random number by said client using said second key, a delivery of said random number and said encrypted random number from said client to said access controller, a decryption of said encrypted number using said updated first key by said access controller, a comparison of said random number and said decrypted number, and a decision to pass at least a portion of said instructions if said comparison finds a match of said random number with said decrypted number, and a decision not to pass said at least a portion of said instructions if no match is found.