Mesh-network
The OLPC XO-XS laptop-xtablet are equipped with wifi and the little ears are actually dual antenna's. With those the XO-XS can video call each other within a range of about 200 m, but they can also serve as a "bridge" or a "relay", between 2 XO's that are more than 200 m apart from each other. The middle XO or XO's will then function as a "bridge" or "relay" and allow the two users to video talk to each. But it doesn't stop at 2 or 3 XO's: when there is a regional deployment of XO's it may very well happen that kids live in each others neighborhood and the good news then is that they can continue collaborating because all of their XO's make and become part of a complete wireless network. This is what is referred to as a Mesh-network.
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