04 Try it yourself Interactive

Watch the TTL count down and the hops appear

The same five devices from section 02, the same addresses, R3 still silent. Traceroute runs four rounds, one probe each, and the TTL value sits on the packet at every device so you can watch it fall to zero at the exact hop that then reports. Ping sends one echo request through the same three routers with a normal TTL and gets one reply, which is the contrast worth having: ping crosses the path and never learns what is in it. Watch the two cards below the packet, and the Hops named counter. Nothing plays on its own: Next, Back and Reset, or the arrow keys.

Traceroute · S to 198.51.100.20
nothing sent yet, no hops known
Indigo is the device holding or sending the packet. Amber is a device that forwarded it. Rose is a device that discarded it because the TTL reached zero. Green is a device that answered. The TTL cell on the packet turns rose the moment it hits zero.
Press Next to begin. Each press moves the run one step.


      
Probes sent0
Probe TTL
Hops named0
Destination reachedno
step 0 / 0