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RICOCHET I"iETWORK DESCRIPTION Ricochet TM is an innovative network that enables high speed, low cost, wide area access to on-line services, the Internet, LA~l\l applications, and peer devices. Ricochet networks employ trequency- hopping, spread spectrum, packet radios, installed geographically in a mesh topology. Through a unique combination of Ricochet's wireless cloud and its wired backbone, data packets travel through the network at high speeds within a cormnunity, across a city, and £rom city-to-city. Ricochet wirelessly enables high speed, low cost access to peer-to-peer communications, on-line services, LANs, and telephone modems. Ricochet packet radio repeaters [poletops] are shoe-box size and require low power levels; they can be simply deployed on utility pole-tops or roof-tops. These poletop radios support 100 kilobits per second (kbps) raw speed, typically provide between 10 to 45 (kbps) of continuous user-data throughput (depending upon soft....vare, hardware, and applications run), and are capable of burst user-data speeds to ïO kbps. Poletop radios are deployed in a cluster trom one-half mile to two miles apart in a mesh topology. This mesh topology makes Ricochet extremely flexible and expandable. Each poletop radio constantly knows the identity of, location of (longitude and latitude), and its ability to communicate with other poletop radios within its range. In addition, each serves as an entrance or an exit to the netwo:-k, so data packets can enter and exit the network at any poletop radio location. Once in the network, data packets can "hop" around busy or non-functioning radios. Expanding coverage, ir:creasing capacity, or achieving cormnunications in dead spots is simply a matter of installing one or more additional poletop radios. Clusters of poletop radios are interconnected with a high-speed data network running on a frame relay or a similar \vired ser-.;ce. Data packets move from poletop radios to this high speed wired network through a Wired Access Point [\VAP] that is located in the center of each cluster of poletop radios. A \V.-\P cO:1sists primarily of radios to handle traffic to and from the cluster; a packet switch conversion cO!":1puter to convert and route packets to and from wireline services; and a leased-line \vith èÜgh speed access to wireline packet s'Witch services. The network is designed so that a data packet should require no more than t\VO to three hops before reaching a \V AP. Packets can move from a W..ðJ> in one city to a W AP in another city through Network Interconnection Facilities [1\lFs], which control the movement of packets across Ricochet's wide- area-network. Data tram an application will hop from a subscriber device to the nearest poletop radio, and then will hop trom poletop radio-to-poletop radio, to W AP, to NlF until reaching its destination. Destinations may include another subscriber device, a public packet switched network (e.g., Internet on-ramp), on-line service, or LA.:.~. Ricochet's subscriber de~ice pro~ides the final piece of a seamless wireless data communications solution. Ricochet's subscriber device uses the Hayes™ AT command set and is compatible with most popular applications. The current generation of subscriber devices is a portable radio modem that connects ""ith a cable to the serial port of a computer or PDA Because the modem is functionally equivalent to poletop radio, portable modems can talk directly to each other without access to our mesh netv.·ork. Future generations of subscriber devices will include a PCMCIA card, combined ""ireline-wireless modems, and outdoor telemetry units. .. . . ~.. , ....... I