[Testing] first play with new XO 1.5 machines

Tomeu Vizoso tomeu at sugarlabs.org
Thu Oct 22 05:37:23 EDT 2009


On Thu, Oct 22, 2009 at 03:03, Daniel Drake <dsd at laptop.org> wrote:
> 2009/10/22 Martin Langhoff <martin.langhoff at gmail.com>:
>> They are -- but it's pretty awkward to activate. I am arguing that
>> ad-hoc networking with a preset ESSID, and Salut should be the
>> transparent fallback. Just like the mesh was on earlier releases.
>
> We already discussed this a lot in another thread. It should not be
> automatic. The thread is titled "[Sugar-devel] [Design] Ad-hoc
> networks - New Icons"
>
> The biggest headache about mesh is the cases where it sort-of-works,
> but not quite. Ad-hoc networking will be considerably less reliable
> than mesh was, for a few reasons:
>
> 1. In the mesh, everyone does their own beaconing. Sounds horrible but
> it actually works.
> In ad-hoc, there is just one beacon master. Due to cheap radios and
> interference etc, the beacon master will switch around frequently
> causing frequent network splits and communication failures.
>
>
> 2. This kind of situation will happen frequently:
>
> A <-----> B <-----> C
>
> B can see both users A and C on his network view. A can only see B,
> and C can only see B.
> B shares an activity. Both A and C join. However, anything done by A
> cannot be seen by C and vice-versa, because they are too far apart.
>
>
> 3. Another nasty situation
>
> A -------------------------- B
>
> A and B are outside of radio range, but are both setup to start an
> automatic network named "olpc"
> So they both setup their own ad-hoc networks, both becoming beacon masters.
>
> Another laptop "C" comes along
> A <--------> C <----------> B
> This laptop can see both of these independent laptops (each having its
> independent network). It can join one or the other. It cannot join
> both. Hence this XO can only communicate with A or B, but not both
> (even though the range is OK), and presenting this choice in the UI
> would be nasty.
>
>
> Ad-hoc will work well for the cases where the children get together in
> a small space and explicitly create a throwaway network. If it is
> created automatically, I predict we will just get an unreliable mess.

What would be more reliable in the under a tree use case: ad-hoc or
mesh with a max of 1 hop?

Thanks,

Tomeu

-- 
«Sugar Labs is anyone who participates in improving and using Sugar.
What Sugar Labs does is determined by the participants.» - David
Farning



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