What does this trace route show

Trace Route (traceroute / tracert)

Trace Route is a command line tool to trace the path of data packets in an IP network and to make them visible. The point is to determine which stations a data packet takes to its destination. Trace Route works in a similar way to ping. With this tool, however, you get even more information about the network connection between the local station and the remote station.
Trace Route is on the command line / console as a command traceroute under Unix / Linux and tracert on Windows to disposal. The remote station can be addressed under the IP address or the domain or WINS name. If necessary, Trace Route takes over the name resolution.
Trace Route has several options that provide more information. We will not go into this further here. The help system of the operating system provides information on this.

Example of the use of Trace Route (tracert)

C: \> tracert -d www.elektronik-kompendium.de Route tracking to www.elektronik-kompendium.de [] over a maximum of 30 sections: 1 1 ms 1 ms 1 ms 2 64 ms 68 ms 70 ms 3 60 ms 60 ms 61 ms 4 62 ms 63 ms 63 ms 5 70 ms 71 ms 71 ms 6 69 ms 71 ms 71 ms 7 69 ms 71 ms 71 ms 8 81 ms 73 ms 72 ms 9 71 ms 71 ms 70 ms Trace ended.

What happens at Trace Route?

When executing the tracert or traceroute command, several ICMP commands (ping) are sent one after the other to the target address. With the first ICMP command, the TTL value of the IP packet is set to "1". The TTL value indicates after how many stations the lifetime of an IP packet expires. The station that recognizes the expired lifetime of the data packet discards the packet and sends back an ICMP message of type 11 "Time Exceeded". After the arrival of the ICMP message "Time Exceeded", another ICMP command is sent with the TTL value increased by one. This is repeated until all stations or the route to the destination address has been determined. The result is displayed on the screen.

Use of Trace Route

  1. Trace Route can be used to check whether the data packets are using the correct route on the way to their destination. A detour can e.g. B. indicate a failure of a router.
  2. Trace Route can be used to check the runtime between the individual stations. In this way, a bottleneck on the transmission path can be determined.
  3. If IP packets do not reach their destination, you can use Trace Route to determine the station that has failed.
  4. If one or more stations occur more than once within a route, it is likely that the corresponding router is causing a routing loop due to an incorrect routing entry.

Incorrect trace route:

C: \> tracert -d www.microsoft.com Route tracking to www.microsoft.com.nsatc.net [] over a maximum of 30 sections: 1 1 ms