On Sat, 2008-05-24 at 19:29 +0200, Juliusz Chroboczek wrote:
> > According to my understanding 802.11s is more like a switching technology
> 
> I'm not sure what you mean.  Switching is not fundamentally different
> from routing, it just works at a different protocol layer.

Exactly. But the term "routing" usually applies to layer 3 and not layer
2. And to rule out confusion, I strongly propose to use "routing" for a
layer 3 gateway (and only for that) and "switching" and/or "bridging"
for a layer 2 gateway (in OSI speak[0]).

> Contrary to what some people seem to believe, modern switches do use
> a proper routing protocol.  Ethernet switches (IEEE 802.1D) use the
> Spanning Tree Protocol, and Token Ring switches use a form of source
> routing with path reversal.

And I'm told that Cicso switches have there own proprietary protocol to
detect loops on layer 2.

> So in some sense IEEE 802.11s is a standard for switches, except that
> it uses a much more refined routing protocol.
> 
> > Since swithces broadcast they cannot be used between two different
> > network like olsr can.

Switches also broadcast. But most are unicast (unless you run lots of
Win* hosts - they seem to be pretty fond of broadcasting).

> This is wrong.  IEEE 802.11s has provisions for integrating non-mesh
> links.  But your basic intuition is right, the mechanism is much more
> involved than the ones that can be used at layer 3.  (Basically
> 802.11s uses a degenerate form of source routing in that case.)
>
> Obviously, this will only work if the non-mesh networks use the
> IEEE 802.2 frame format (Ethernet will work, but PPP won't, at least
> not without some extra effort).

I would use OLSR (or any other routing protocol) at most to route in
between different 802.11s clouds. But perhaps I'm only old-fashioned and
there will be good reason for other uses;-)

	Bernd

[0]: For the curios, layer 1 gateways are usually called "repeater" (or
     "amplifer" in the analog world). Layer 7 gateways are "proxies" and
     similar.     
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