A system and method is provided for measuring network round trip time by monitoring fast-response operations at one network endpoint, typically a client computer. A client computer of the system includes a network monitoring and analysis engine which monitors a sent packet for a fast-response operation. If a fast-response operation is detected, then the client computer assumes a server computer processed the packet substantially instantaneously. Thus, the processing time at the server computer is neglected as zero. The round trip time can then be approximated as the difference in time between when the client computer sent the packet and when the client computer received the response packet.