kernel driver removals

[Dan Williams]

On Thu, 2007-01-25 at 20:49 +0800, David Woodhouse wrote: 
> On Thu, 2007-01-25 at 07:50 -0500, Dan Williams wrote:
> > I believe we're going to need NAT for the mesh portal stuff; where the
> > laptop automatically becomes a mesh portal by attaching to an
> > infrastructure AP and bridging traffic between eth0 and msh0.
> 
> Are you imagining that we'll be running Legacy IP on the mesh? I thought
> it was only going to be IPv6?

You're correct of course, it should be IPv6 only.

Just thinking off the top of my head, but we may need to NAT because the
AP isn't going to understand the 4-address 802.11s frame format the mesh
uses, which is why we have to NAT.  We can't just pass 802.11s frames
from msh0 to eth0 because the headers on msh0 are 4-address and the
headers on eth0 must be only 3-address for compatibility reasons [1].

Even if the AP did support WDS (ie it has some understanding of
4-address headers), you usually have to manually configure the WDS nodes
that the AP will accept the 4-address frames from, which clearly won't
work here.

The way to take all NAT and the double-bridging out of the picture is to
have all APs be mesh portals and bridge between the mesh and an ethernet
link on the AP.  But that will only be possible where there is OLPC
hardware installed that understands the mesh, and certainly isn't enough
for testing.

I may be completely wrong here; Javier?

Dan

http://madwifi.org/wiki/AboutWDS

[1] Unless an AP explicitly supports 4-address frames and/or WDS, it
usually only pays attention to 3 addresses, hence the problem.