US Patent 9350748 Countering service enumeration through optimistic response

Techniques for improving computer system security by detecting and responding to attacks on computer systems are described herein. A computer system monitors communications requests from external systems and, as a result of detecting one or more attacks on the computer system, the computer system responds to the attacks by modifying the behavior of the computer system. The behavior of the computer system is modified so that responses to communications requests to ports on the computer system are altered, presenting the attacker with an altered representation of the computer system and thereby delaying or frustrating the attack and the attacker.