> To answer your original question, I'm not aware of any systems that
> provide a error message for such a setup. Some, as has been mentioned
> elsewhere, will just drop the packets on the floor with creative use of
> filters, but I'm not aware of any systems that will send an error
> message back.
Well, there are systems out there that return ICMP destination unreachable
messages.
aviator:3 $ traceroute -n 204.128.145.3
traceroute to 204.128.145.3 (204.128.145.3), 30 hops max, 40 byte packets
1 128.227.224.100 3 ms 3 ms 2 ms
2 128.227.162.1 3 ms 3 ms 3 ms
3 128.227.254.2 4 ms 5 ms 4 ms
4 128.227.252.10 10 ms 14 ms 31 ms
5 192.221.6.13 76 ms 56 ms 84 ms
6 192.221.48.1 179 ms 147 ms 130 ms
7 * 192.221.42.100 136 ms 157 ms
8 * * *
9 * * 192.221.42.100 168 ms !H
10 * 192.221.42.100 87 ms !H *
11 * 192.221.42.100 153 ms !H *
For more info about ICMP type 3, consult
ftp://rs.internic.net/rfc/rfc792.txt
"
If, according to the information in the gateway's routing tables,
the network specified in the internet destination field of a
datagram is unreachable, e.g., the distance to the network is
infinity, the gateway may send a destination unreachable message
to the internet source host of the datagram. In addition, in some
networks, the gateway may be able to determine if the internet
destination host is unreachable. Gateways in these networks may
send destination unreachable messages to the source host when the
destination host is unreachable.
"
And, yes, the packets do not bounce around FOREVER. Nor are they limited
to 15 hops, or none of the providers in Gainesville (each of which is 16-22
hops away from the University of Florida, also in Gainesville) would be able
to reach the U. Traceroute often gives up around 30 hops.
Traceroute uses ICMP type 11: Time Exceeded