were used to establish the connection to the target computer. Traceroute or Tracert works with the ICMP protocol and sends IP data packets to the target computer. Before counting down the time-to-live (TTL) data field and then forwarding it, the routers evaluate it and send the ICMP response for the TTL value and the transmission duration back to the source address
(SA) entered in the IP data packet. Thetest is performed several times with the TTL value constantly increased by the amount "1" until the data packet has reached the destination address
and all Internet nodes with their transmission times have been recorded. The traceroute procedure varies somewhat depending on the operating system.
Windows, for example, works with ICMP packets and tracert.exe, while Unix uses the UDP protocol and there are separate implementations for the TCP protocol: Tcptraceroute or Layer Four Traceroute (LFT).