Secure client-server communication

A client-server connection method performed by a server to establish a secure communication channel with a client, the method comprising:

• receiving a request from the client to establish a secure communication channel, wherein the client request is a request for the server to issue an access token within an authorization protocol;
• generating a client-side credential in response to receiving the request from the client, wherein the client-side credential comprises the access token used for establishing security on the communication channel;
• generating a server-side credential and subjecting the server-side credential to a one-way function to create a hash code;
• containing the server-side credential in a cookie of a type that cannot be accessed by the client;
• containing the hash code in the client-side credential;
• transmitting the client-side credential and the cookie to the client;
• receiving the client-side credential containing the hash code and the cookie containing the server-side credential from the client over the secure communication channel, wherein the client-side credential is contained in an authorization header;
• validating the access token;
• triggering an authentication component to perform an additional check based on the cookie in response to the access token containing a hash value, wherein the additional check comprises checking if a cookie with a random value exists;
• reapplying the one-way function to the random value to obtain a new hash value in response to the cookie with the random value existing;
• comparing the new hash value with the hash value contained in the access token;
• and
• indicating the access token valid in response to the new hash value matching the hash value contained in the access token.