A transmitted transport communication protocol (TCP) packet in an established TCP connection is intercepted and resent with a modified IP layer to determine network nodes within a network path. No new connection is required, and the data may be transmitted to its intended location as part of the existing connection, bypassing firewalls and other obstacles commonly affecting ping commands. The change to the IP layer may include a modified TTL value. Address location and response time may be determined for each node in a network path.