The $100 Laptop

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The $100 Laptop

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Mesh to Internet

Mesh Networking

Access to the Internet Is Just a Mesh Away.

One of the goals of the $100 Laptop program is to provide access to local networking and to the Internet for children across America and around the world. The children most likely to receive a $100 laptop will not have access to or be able to afford a direct connection to the Internet, and there will be no skilled network administrators in many areas. The solution to the connectivity issue lies in the emerging technology of mesh networks, which automates the creation of a resilient network. Even if no connection to the internet is available, the nodes in the mesh can communicate with each other, like an office LAN (local area network), without requiring any administrative set up or oversight. Joining the local mesh is no more complicated than turning on the computer.

Roughly following “Tech Target” and "Telecom Glossy 2K” definitions, we define a mesh network as follows: "A mesh network is a network that employs one of two connection arrangements, full mesh topology or partial mesh topology. In the full mesh topology, each node is connected directly to each of the others. In the partial mesh topology, nodes are connected to only some, not all, of the other nodes." Note that these definitions mention no dependency on any time parameter -- nothing is necessarily dynamic in a mesh. However, in recent years, and in connection with wireless networks, the term "mesh" is often used as a synonym for "ad hoc" or "mobile" network. So, when we speak of a wireless mesh network, we assume a network that handles many-to-many connections and is capable of dynamically updating and optimizing these connections.

To better understand the concept, think of our potential customers in Cambodia. If a school in Cambodia had a hardwired Internet connection (backhaul), they could use a WiFi signal to transmit a wireless connection outside of the school. As each logged on to the network, each students laptop would act as a node in the mesh network and add to the reliability of the overall system. The school could then minimize its costs of broadcasting its single by installing a minimal amount of radio towers around the school to provide access to all of the students. In a simplified example, the mesh network is self-healing, as it finds the best way to keep a user connected.

Simple Mesh

It is important to remember that the mesh network can be anchored by physical connections to the Internet. In the mesh network, they refer to these hard-wired connections as the backhaul. The mesh network can either support many users to a single backhaul, or provide multiple routes to multiple backhauls through the interconnection of the nodes in the mesh. Large mesh networks utilize mesh routers strategically located throughout the network. The routers send signals directly to the backhaul and reduce the number of “hops” any users has to make to get to the backhaul. The nodes or hops in the network help to create stability in the network, but too many hops will slow the response time down. In intelligent mesh networks, the network dynamically determines the best route through the nodes to connect two ends points or in our case two students. When a network break is detected, like a student turning off his or her computer, the network will dynamically determine a new route.

This type of “self-healing” routing is demonstrated in the following video clip showcasing how the Innovative Wireless Technologies mesh system functions. In the clip, you can see how the mini-grids form based on usage and nodes active in the mesh and how the system finds alternative routes when a user drops off.

To see a mesh network model in action, click on the following diagram:

Mesh Network Diagram

The open standard radio technology is creating a competitive environment driving down the costs of optimizing the performance of a mesh network.

The success of the $100 laptops will be compounded by its ability to provide cheap access to the Internet. High volume, open standard radio technology (802.11Wi-Fi, 802.16 WiMax, and future standards) offers the needed platform for the $100 Laptop to network and to gain access to the Internet. Industry coalescence around standards has enabled price, performance and functionality points such that Wi-Fi is now the world’s first global broadband unlicensed radio standard. With this global standard, devices ranging from laptops to PDA’s to cell phones will all provide the needed network to support the $100 laptop with the mesh network needed to get connected. As the number of $100 Laptop owners increase in a given area, the network will grow in strength and reliability, exhibitiing the virtuous circle of network effects.

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Five©2005 WEMBA 2006 Group 5 Fall 2005