which is a very important step in the growth of wireless. (Chapter 15 discusses the details of Bluetooth.) Another disadvantage of wireless HANs is that generally, depending on the type of wireless network or standard selected, there may be bandwidth limitations. But more importantly, wireless also has unresolved security issues, network infringe- ment issues, interference from other wireless sources, and various performance issues. (Chapter 13 discusses wireless behavior, and Chapter 15 describes the wire- less communication standards applicable to home area networking in more detail.) Control Networks Control networks are typically low-speed powerline networks (see Figure 12.14). The most widely used technologies for home automation and control purposes are based on three standards: LonWorks-Echelon Corporation's LonWorks (www.lonworks.com) is an open standard under EIA 709 that provides a solution to the many prob- lems of designing, building, installing, and maintaining control networks. LonWorks networks can range in size from 2 to 32,000 devices and can be used in everything from supermarkets to petroleum plants, aircraft to rail- way cars, fusion lasers to slot machines, single-family homes to skyscrap- ers. The trend now is to move away from proprietary control schemes and centralized systems to open, off-the-shelf chips, operating systems, and parts to build products. The LonWorks protocol is now embedded in sili- con neuron chips from Cypress Semiconductor (www.cypress.com), Toshiba America (www.toshiba.com), and other companies. Dozens of manufacturers are incorporating these chips into their modules for control- ling household electrical equipment, providing interoperability, robust technology, faster development, and scale economics. X10-As mentioned earlier in this chapter, X10 is a communications proto- col for remote control of electrical devices and communications over stan- Telephone Home Control Interface Burglar Alarm Responder for PC Interface Remote-Controlled Lamps and Appliances Command Si