Subject: Re: gsip sends byte-swapped vlan tags
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: Manuel Bouyer <>
List: tech-net
Date: 01/27/2006 21:15:20
On Thu, Jan 26, 2006 at 08:14:20PM -0500, der Mouse wrote:
> > The issue here is that the equipement can neither fragment nor return
> > a ICMP error message, because it's not an IP equipement.  The packet
> > is just dropped.
> Then it's the IP encapsulation layer that's broken, for trying to send
> a too-large packet over it.  The IP layer needs to know the MTU of the
> link, and deal with it.
> After all, this is how Ethernet works too: try to send a too-big packet
> and it simply won't make it.  It's the IP-over-Ethernet layer that
> handles fragmentation &c.  The same needs to happen here.
> Any provider that tries to sell a thing such as you describe as an IP
> transport should be prosecuted for fraud.

Why ? It's not really his fault. If I remplace the ADSL-ethernet bridge
with an ADSL-ATM, or a good (if this exists) integraded ADSL modem/router
then there's no MTU problem. The problem is on *my* equipement. And
I can't change it (where can I buy an ATMF25 sbus adapter, with documentation
to write a driver ?)

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference