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Return Path?
- Thread starter uuallan
- Start date
Traceroute is really just a series of icmp echo packets with ttl incrementet from 1 and up to 30 (hops).
Tracing the route the packet go back, would require the remote site to manipulate the ttl's of the packets it sends out.
It's a long time since I've read the ICMP rfc's, but the functionality must (as far as I can see) be implemented in the tcp/ip stack of the remote site. I have not seen any such implementions or utilities yet. Try to get telnet access to the remote site, and try a trace from there.
Tracing the route the packet go back, would require the remote site to manipulate the ttl's of the packets it sends out.
It's a long time since I've read the ICMP rfc's, but the functionality must (as far as I can see) be implemented in the tcp/ip stack of the remote site. I have not seen any such implementions or utilities yet. Try to get telnet access to the remote site, and try a trace from there.
Guest_imported
New member
- Jan 1, 1970
- 0
Sure there is! Just use PING's -r switch to record the route up and back (maximum of nine hops).
For example:
ping -r 9 server.somewhere.net
Pinging server.somewhere.net [192.168.16.20] with 32 bytes of data:
Reply from 192.168.16.20: bytes=32 time=45ms TTL=126
Route: 10.1.20.90 ->
192.168.16.20 ->
172.16.10.1
For example:
ping -r 9 server.somewhere.net
Pinging server.somewhere.net [192.168.16.20] with 32 bytes of data:
Reply from 192.168.16.20: bytes=32 time=45ms TTL=126
Route: 10.1.20.90 ->
192.168.16.20 ->
172.16.10.1
Guest_imported
New member
- Jan 1, 1970
- 0
(sorry) I should not have said "up." The -r switch records the return path only.
Doesn't work for me:
Pinging [66.77.74.20] with 32 bytes of da
Reply from 66.77.74.20: bytes=32 time=331ms TTL=234
Reply from 66.77.74.20: bytes=32 time=330ms TTL=234
Reply from 66.77.74.20: bytes=32 time=331ms TTL=234
Reply from 66.77.74.20: bytes=32 time=430ms TTL=234
Ping statistics for 66.77.74.20:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 330ms, Maximum = 430ms, Average = 355ms
What protocols will this techniq use. Which OS/version of ping do you use. I would like to know. Seems like simular functionality to strict or loose source route.
I browsed through some rfc's and found that my memory betrayed me. Traceroute uses udp packets with increasing ttl, not icmp echo reply. Then it interpret icmp replies.
-katamann
Pinging [66.77.74.20] with 32 bytes of da
Reply from 66.77.74.20: bytes=32 time=331ms TTL=234
Reply from 66.77.74.20: bytes=32 time=330ms TTL=234
Reply from 66.77.74.20: bytes=32 time=331ms TTL=234
Reply from 66.77.74.20: bytes=32 time=430ms TTL=234
Ping statistics for 66.77.74.20:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 330ms, Maximum = 430ms, Average = 355ms
What protocols will this techniq use. Which OS/version of ping do you use. I would like to know. Seems like simular functionality to strict or loose source route.
I browsed through some rfc's and found that my memory betrayed me. Traceroute uses udp packets with increasing ttl, not icmp echo reply. Then it interpret icmp replies.
-katamann
- Status
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