New technologies usually go through two phases. First, people look for reliability; once that is achieved, they buy convenience. Often, years separate these two stages. Device networking is so complex that it requires the two to develop in tandem. This is one technology in which convenience is reliability.Today the first phase is being attacked by a number of middleware programs that might be thought of as operating systems for device networks. These address such issues as scalability, connectivity and maintenance. (Their sector name is mesh computing.) They come in three general flavors:proprietary (MillennialNet, SensiMesh), open-source (TinyOS) and ZigBee, the product of an industry consortium of the same name numbering nearly 200 companies. ZigBee 1.0, which was announced in June 2005, is optimized for allowing a large number\u2014thousands\u2014of extremely low-power devices to communicate wirelessly. Sample applications that might run on ZigBee include room-by-room sensing of utility consumption to allocate costs more precisely and improve conservation, and use of wireless monitors to define security perimeters as needed.Convenience programs run on top of these standards. These programs, for instance, might be tools that sort devices into functional groups, so that all devices that perform one type of task can be addressed with a single command (\u201cTurn off all the valves!\u201d), or compression algorithms that decipher sensor data locally and transmit just the necessary bits, thus avoiding the need to pump huge amounts of trash over the network. (Especially useful in the case of cameras.) Until recently, most user companies wrote their own convenience programs, but today vendors are beginning to enter what appears to be a growing market.