Both EDGE and 1xRTT are 3G standards, as defined by the ITU, but are usually marketed as 2.9G due to their comparatively low speeds and high delays when compared to true 3G technologies. Typical 2G standards include GSM and IS-95 with extensions via GPRS, EDGE and 1xRTT, providing Internet access to users of originally voice centric 2G networks. Originally 2G networks were voice centric or even voice only digital cellular systems (as opposed to the analog 1G networks). Cellular network technologies are often split into 2nd generation 2G, 3G and 4G networks. One typical characteristic of WLANs is that they are mostly very local, without the capability of seamless movement from one network to another.Ĭellular networks or WAN are designed for citywide/national/global coverage areas and seamless mobility from one access point (often defined as a base station) to another allowing seamless coverage for very wide areas. These however are no longer in widespread use. Older systems that provide WLAN functionality include DECT and HIPERLAN. Typically a WLAN offers much better speeds and delays within the local network than an average consumer's Internet access. These systems are used to provide wireless access to other systems on the local network such as other computers, shared printers, and other such devices or even the internet. WLANs are often known by their commercial product name Wi-Fi. An example of a WSAN would be a collection of sensors arranged throughout an agricultural facility to monitor soil moisture levels, report the data back to a computer in the main office for analysis and trend modeling, and maybe turn on automatic watering spigots if the level is too low.įor wider area communications, wireless local area network (WLAN) is used. While most individual nodes in a WSAN are expected to have limited range ( Bluetooth, ZigBee, 6LoWPAN, etc.), particular nodes may be capable of more expansive communications ( Wi-Fi, Cellular networks, etc.) and any individual WSAN can span a wide geographical range. Nodes typically connect in a star or mesh topology. Wireless Sensor Networks (WSN / WSAN) are, generically, networks of low-power, low-cost devices that interconnect wirelessly to collect, exchange, and sometimes act-on data collected from their physical environments - "sensor networks". Some of these technologies include standards such as ANT UWB, Bluetooth, ZigBee, and Wireless USB. Some examples include wireless headsets for mobile phones or wireless heart rate sensors communicating with a wrist watch. Personal area network (PAN) systems are intended for short range communication between devices typically controlled by a single person. Standards can be grouped as follows in increasing range order: Wireless technologies can be evaluated by a variety of different metrics of which some are described in this entry. A wide variety of different wireless data technologies exist, some in direct competition with one another, others designed for specific applications.