Serious problems with "rescan networks on wakeup" feature.

[Thomas Tuttle]

On Sun, 2 Mar 2008 22:37:22 -0500, "John Watlington" <wad at laptop.org>
said:
> 
> On Mar 2, 2008, at 7:49 PM, Thomas Tuttle wrote:
> 
> The problem we have is the following:
> 
> A student is using the laptop away from school/infrastructure, and is in
> simple mesh mode.   In this mode, all service discovery and collboration
> is multicast.    The student puts their computer to sleep (by closing  
> the lid)
> and goes to school.   Once they arrive at school, the last thing we want
> is for their laptop to try to use simple mesh --- it trashes spectrum  
> and makes
> the school network not work, plus they won't see any of their friends  
> that
> are (properly) connected through the school presence service.
> 
> If we naively followed your suggestion above, the laptop would of course
> discover that the previous network state (simple mesh) was fine, and it
> would never discover that there were centralized services available.
> 
> This reply is intended to spark discussion about better fixes.
> 
> For example, how about only rescan when the laptop was in simple mesh
> mode when put to sleep, or if an attempt to reestablish the existing  
> connection
> fails ?

That sounds good, actually.  Basically, if there's a better connection
available, use it, but if we have a known-best one (i.e., an AP), stick
with it.

I think this should be configurable, so deployments could decide the
best way to do it based on their coverage, and G1G1 users could put
their favorite (i.e. home/work/school) APs first.  Ooh, there's an idea
-- could there be a "preferred ESSID" list that is tried before mesh? 
My XO knows about my school network, but never uses it until it's tried
a mesh first.

Cheers,

Thomas Tuttle