Re: firewall, reject: icmp vs. tcp

Ulrich Windl (Ulrich.Windl@rz.uni-regensburg.de)
Wed, 10 Apr 1996 14:10:48 +0100


On 9 Apr 96 at 14:59, Alan Cox wrote:

> > e.g. "ipfwadm -I -a reject -S <source> -D <dest> <port> -P tcp", then
> > on the host <source> requesting for that connection, ICMP packets
> > arrive telling something like "port unreachable".
> >
> > unfortunately, some tcp/ip stacks, at least win/NT and w95, do not understand
> > these icmp packets and continue to try to open a connection until a timeout
> > occurres.
>

#if YOU_LIKE_STANDARDS
It really makes me angry that big companies don't obey the standards
even when they complain to implement one. For eyample Win95 does NOT
implement DHCP correctly; as Alan indicates they didn't implement IP
correctly, too. But people buy these things and then they complain...
#endif

> I would suggest you refer the problem to microsoft. Using reject also upsets
> older HP/UX machines in fun ways. I'd refer that to HP (and get an up to
> date HP/UX.
>
> Alan