Obviously there will be growing pains with the networking topology and yes there are trade-offs when one goes with a mesh network.
The thing is though, your solution always requires an additional piece of hardware, a power source for that hardware, and someone to maintain it. Since the OLPC is being marketed at areas where all of those items are in limited supply you might be surprised to find that your first-world solutions aren't always going to be practical.
(BTW - a solution that requires you to go outside of your design restrictions is not a valid solution.)
The best of ZDNet, delivered
ZDNet Newsletters
Get the best of ZDNet delivered straight to your inbox
