[MLB-WIRELESS] So how does this routing bit work?

[vortex]

On Friday 29 March 2002 11:49 pm, Hamish Moffatt wrote:
> On Fri, Mar 29, 2002 at 10:41:31PM +0000, vortex wrote:
> > look. ethernet frames do not route. neither do 802.11b frames.
>
> Ethernet can be 'switched.'

Yes. But there are no global swithed ethernet segments - and for good reasons 
- the underlining distribution mechanism just doesn't scale well. it does 
well what it does best - and that is deliver efficiently in a local wired 
environments.

 The effect is the same as routing - delivery
> decisions are made based on the source/destination address.

No the effect is not the same. For instance - there is no global frame route 
distribution for MAC addresses. And if there were, it would be horribly 
inefficient. You think central Internet routers' BGP tables are large today! 
Just consider the unweidly size of a dynamic MAC routing protocol. Infeasible.

> > switching doesn't make sense in 802.11b.
>
> Why not? The network is not completely broadcast. There are different
> channels, and there are directional antennas. In this case, if routing
> is needed then switching could also be used.

802.11b has a diferent contention protocol. And I don't see simultaneous 
transmission on multiple wlan channels as switching - it's more like 
multiplexing lines (like MPPP for multiple modems to aggregate bandwidth). 


> I'm not saying that it should be used, only that it is technically
> possible.

Sure. And I agree with you in that it _could_ be used & *is* possible. I'm 
just saying that implementing this will have lasting (detrimental) 
consequences.

.vortex