tracert question...two hops on the same address?

joshmadakor

I was just messing around, pinging and tracing addresses in my "neighborhood" WAN when I came across this:

Tracing route to 71.197.148.10 over a maximum of 30 hops

1 <1 ms <1 ms 1 ms 192.168.1.1

2 13 ms 11 ms 18 ms 73.98.10.1

3 21 ms 18 ms 19 ms 71.197.148.10

4 18 ms 17 ms 17 ms 71.197.148.10

Trace complete.

Anybody know what would cause this? I've never seen it before and I'm a newb.

++Rep for insight

Roguetadhg

First reply:

No loop, #3 and #4 are the same device. It just used the same IP for
it's source address in the ICMP TTL expired msg and the icmp echo reply
msg.

If you research the way traceroute (in windows) works this makes sense.
Check out:

[URL="http://www.visualware.com/resources/tutorials/tracert.html"]http://www.visualware.com/resources/...s/tracert.html[/URL]

Second:

I've seen this with some brands of firewalls. Either both are the
firewall or the first 10.162.248.1 was the firewall, then next is an
end device. I think that was with Checkpoint or Pix that I experienced
that-but honestly can't remember exactly which. And of course, your
particular config makes a world of difference.

Source: Tracert returns same IP address two or three times

joshmadakor

Thank you so much sir. That's very interesting.