Re: Traceroute *s with portmasters (fwd)

dan_hubbard@ismbc.com
Thu, 04 Jul 1996 09:54:40 -0700

New release of COMOS now supports Windowz tracert and pings :-)

At 05:53 PM 7/4/97 +0200, you wrote:
>> I don't think the client machines are configured wrong as I have tried every
>> combination I can think of. Is this a Windows bug or a portmaster bug?
>> Does anyone else get this problem?
>
>I asked this a while back, this I got from jstorms@livingston.com:
>
>> From what I've been able to gather, the problem with the win95 'tracert'
>> program is that it uses ICMP packets instead of UDP packets. The idea
>> behind traceroute is to send out a series of packets (UDP packets) with a
>> particular destination address. Each UDP increments the TTL (time to live)
>> by one. Then as the packet is forwarded from hop to hop the TTL is
>> decremented. When the TTL reaches zero an icmp time exceeded message is
>> generated and sent back to the originator which is where all the hops and
>> interesting data comes from. The problem is generating icmp time exceeded
>> messages for icmp packets (as used by microsoft's tracert) with a ttl of
>> zero is not a good idea (all kinds of terrible things can potentially
happen).
>
>So, yes, it is yet another micro$oft "feature" :-(
>
>--Steven.
>
>
------------
Dan Hubbard
Systems Analyst
ISMBC Inc.
dan_hubbard@ismbc.com
(604)451-2364