Subject: traceroute with firewalled routers
To: None <tech-net@NetBSD.ORG>
From: Nick Loman <nick@csosl.co.uk>
List: tech-net
Date: 05/25/1997 14:33:03
Hey there.

Are there any thoughts on the legitimacy of firewalling UDP packets in such
a way that tracerouting a site puts it in a loop?

Does this violate any Internet standards?  Are PIPEX entitled to do this?

Is there any way of getting a useful traceroute output despite this?

Sorry that this is not entirely NetBSD related.

unix# traceroute www.ezcgi.com
traceroute to ezcgi.com (194.131.104.134), 30 hops max, 40 byte packets
 1  unknown1 (194.205.66.130)  3.059 ms  2.958 ms  2.94 ms
 2  lon1gw3.uk.insnet.net (194.177.168.241)  22.257 ms  28.407 ms  26.51 ms
 3  e1.lon1gw1.uk.insnet.net (194.177.160.129)  22.663 ms  22.749 ms
22.636 ms
 4  atm0-2.lon2gw2.uk.insnet.net (194.177.170.196)  24.19 ms  24.198 ms
24.025
ms
 5  fe0.gw1.linx.pipex.net (194.68.130.25)  24.434 ms  24.264 ms  24.273 ms
 6  fddi5-0-0.gw1.london.pipex.net (158.43.194.1)  24.661 ms  24.81 ms
24.714 m
s
 7  fmservice-doc-gw.pipex.net (158.43.16.74)  25.928 ms  26.893 ms  30.011 ms
 8  fmservice-doc-gw.pipex.net (158.43.16.74)  36.058 ms *  30.36 ms
 9  * fmservice-doc-gw.pipex.net (158.43.16.74)  36.317 ms *
10  fmservice-doc-gw.pipex.net (158.43.16.74)  30.779 ms *  31.118 ms
11  * fmservice-doc-gw.pipex.net (158.43.16.74)  34.592 ms *
12  fmservice-doc-gw.pipex.net (158.43.16.74)  30.947 ms *  34.07 ms
^C   

Nick.

---
Nick Loman   (nick@csosl.co.uk)   http://www.csosl.co.uk/~nick/