Patent ID: 7774490

Claim:
A crisscross cancellation system comprising: a device; a crisscross cancellation protocol module coupled to a transport and operating on the device, the crisscross cancellation protocol module configured to send and receive messages via the transport to and from a remote crisscross cancellation protocol module, and the crisscross cancellation protocol module coupled to an application, the crisscross cancellation protocol module configured to exchange message data from the messages with the application; and a set of state variables stored in and maintained by the crisscross cancellation protocol module and used in forming messages sent and in verification of messages received, the set of variables including a nonce variable configured to uniquely identify a current session of the crisscross cancellation protocol module, and including a remote nonce variable configured to uniquely identify a current session of the remote crisscross cancellation protocol module, and including a counter variable configured to uniquely identify the last message sent by the crisscross cancellation protocol module to the remote crisscross cancellation protocol module, and including a remote counter variable configured to uniquely identify the last valid message received by the crisscross cancellation protocol module from the remote crisscross cancellation protocol module.