handed off from the local network, through the 1xEV network, to the Internet." 3.7 MESH NETWORKS A mesh network is a network in which there are at least two pathways to each node. A fully meshed network means that every node has a direct connection to every other node, which is a very elaborate and expensive architecture. Most mesh networks are partially meshed and require traversing nodes to go from MESH NETWORKS WOO'E Figure 3-1 Mini Talker. each one to every other. Mesh networks provide redundancy by supplying multiple pathways to each node. Mesh networks are very well suited for use in vehicle monitoring systems, such as the one developed by MachineTalker The Goleta, California-based start-up has developed MiniTalker, a series of mesh-network-based modular wireless devices that automatically create ad hoc, peer-to-peer WLANs inside vehicles (Fig. 3-1). The devices, which feature built-in environmental sensors, are designed for use on a variety of vehicles-including aircraft, cars, trucks, and trains-and in shipping containers, to measure and report on conditions such as temperature, humidity, and vibration levels. The MiniTalkers will come in various forms for different applications, including stand-alone units that ride along in a vehicle, collecting data, and "tags"-dubbed TagTalkers-that can be attached to a vehicle or a component with Velcro. MiniTalkers are based on the company's MachineTalker a mesh network concept. Machine Talker's technology enhances the mesh network structure by eliminating the need for a powerful, power-hungry CPU. A microcontroller inside each MiniTalker allows the formation of a "local community," with each unit having the ability to freely share information and spot defective network nodes. The proprietary Simple Machine Management Protocol (SMMP) handles network functions. A central unit gathers the WLAN's data and links the information to an external network, such as the Internet or an intranet. CONNECTIONS IN THE AIR-WIRELESS TECHNOLOGIES MiniTalker is designed to give airline