Symmetric-key infrastructure

A system for establishing communication between a client and a server, the system comprising a server computer communicatively coupled to the internet and configured to perform operations comprising:

• receiving, by the server, a request from the client to establish a connection between the client and the server;
• requesting, by the server, use of a previously established shared symmetric key from the client, the previously established shared symmetric key being established for use by the client and the server prior to the server receiving the request, wherein the shared symmetric key is obtained by using a selected key production record and using a key production key;
• receiving, by the server, a response from the client identifying the previously established shared symmetric key;
• determining whether the client is legitimate or attacking the server based on the response from the client;
• and
• based on the determination,
• establishing, by the server, the connection between the client and the server if the client is determined to be legitimate;
• or
• not establishing, by the server, the connection between the client and the server if the client is determined to be attacking the server.

A non-transitory computer-readable storage medium containing instructions that, when executed by a processor, cause the processor to perform a method comprising:

• receiving, by the server, a request from the client to establish a connection between the client and the server;
• requesting, by the server, use of a previously established shared symmetric key from the client, the previously established shared symmetric key being established for use by the client and the server prior to the server receiving the request, wherein the shared symmetric key is obtained by using a selected key production record and using a key production key;
• receiving, by the server, a response from the client identifying the previously established shared symmetric key;
• determining whether the client is legitimate or attacking the server based on the response from the client;
• and
• based on the determination,
• establishing, by the server, the connection between the client and the server if the client is determined to be legitimate;
• or
• not establishing, by the server, the connection between the client and the server if the client is determined to be attacking the server.