On Sun, May 19, 2002 at 10:11:45PM -0400, Andrew Brown wrote:
> >> >Ping has long used a TTL of 255.  Why not do something similar for
> >> >traceroute?  To prevent one from seeing 200+ failure lines traceroute
> >> >could simply stop upping the ttl whenever the past N TTL settings
> >> >failed.  (Eg. if the past 5-10 traceroute TTL's didn't get a reply,
> >> >stop incrementing the TTL and exit.)
> >
> >I don't want to change the behaviour of traceroute (as this suggests),
> >only its defaults.  Behavioural changes like that are more likely to
> >have some sort of ripple effect god knows where.
> 
> ...like traceroute not bothering to actually reach the target due to
> too many hops in between dropping packets for some reason.

IIRC traceroute stops when it receives a 'port unreachable' resonse
from the intended target.
Maybe it should send out the udp packet with a TTL of 255 first.
If it gets a port unreachable response then it can increase the TTL
from one until that happens again, if it doesn't get one then
stopping after a number of non-replies.

	David

-- 
David Laight: david@l8s.co.uk