[MLB-WIRELESS] meshing

[Jason Hecker]

>If person B is smack bang between persons A and C, they're going to do a lot
>of packet forwarding. If person M is between persons A-L on one side and N-Z
>on the other, they are going to be doing an *extreme* amount of packet
>forwarding.

But, if you have a central node that everyone in the region talks to then 
you will still get this problem but to a worse degree.  The central AP 
doesn't have magical hardware that can talk to everyone 
simultaneously.  The amount of collisions it will have to contend with is 
going to be a lot worse than B acting as a routing proxy for A and C.  With 
a strict central node only setup A, B and C must communicate only via the 
central node and I'd say it'll be really, really bad once things get busy 
(ie D and E and F etc talking as well) even if you had two or more cards at 
the central node and forced users A-L to use one frequency and M-Z to use 
another.  I noticed that Megalink who provide internet via 802.11b will 
offer a maximum particular rate but do not guarantee it whatsoever - I 
suspect because the central node topology they have will start getting 
swamped once traffic from more and more users gets onto it.  I'd like to 
know what provisioning they have to maintain a level of service as they get 
more customers (short of subdividing their zones which is a pain because 
all the aerials will be to be realigned).

>them. The routing issues will have to be sorted out a little more
>thoroughly, but it will give us more overall bandwidth to play with if we
>use a backbone-style topology.

I agree.  Some sort of access control may be needed as well to ensure the 
integrity of the Melbwireless VPN within the general 802.11b hubbub that is 
on 2.4GHz.

>IMHO we're going to end up with two main types of nodes: 1) leaf nodes and
>2) everything else.

Even the Seattlewireless document with it's talk of BSS and IBSS (which 
appears to not be available on all 802.11 hardware) concedes that to deal 
with the hidden node transmission everyone needs to be a router.  OSPF 
would hopefully obviate the need for BSS/IBSS compatability issues to solve 
the same problem.


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