Standards, whether established by standards bodies or leading system suppliers as de facto standards, will play an increasing role in system development.

Many different formats for standards and specifications are emerging in home networking, including the following:

• IEEE 802.11 wireless LAN—The IEEE 802.11 standard defines the protocol for two types of networks: ad hoc and client/server networks. An ad hoc network is a simple network in which communications are established between multiple stations in a given coverage area without the use of an access point or server. The standard specifies the etiquette that each station must observe so that all stations have fair access to the wireless media. It provides methods for arbitrating requests to use the media to ensure that throughput is maximized for all users in the base service set. The client/server network uses an access point that controls the allocation of transmit time for all stations and allows mobile stations to roam from cell to cell. The access point is used to handle traffic from the mobile radio to the wired or wireless backbone of the client/server network. This arrangement allows for point coordination of all of the stations in the basic service area and ensures proper handling of the data traffic. The access point routes data between wireless stations or to and from the network server (http://www.wlana.com).

• a 2.4 GHz band using a relaxed IEEE 802.11 standard and digital European cordless telephone standard

• Bluetooth—Bluetooth radio technology provides a universal bridge to existing data networks, a peripheral interface, and a mechanism to form small private ad hoc groupings of connected devices away from fixed network infrastructures. Designed to operate in a noisy RF environment, the Bluetooth radio uses a fast-acknowledgment and frequency-hopping scheme to make the link robust. Bluetooth radio modules avoid interference from other signals by hopping to a new frequency after transmitting or receiving a packet (http://www.bluetooth.com).

• SWAP 1.0—The SWAP system can operate either as an ad hoc network or as a managed network under the control of a connection point. In an ad hoc network, where only data communication is supported, all stations are equal, and control of the network is distributed between the stations. For time-critical communications such as interactive voice, a connection point is required to coordinate the system. The connection point, which provides the gateway to the PSTN, can be connected to a PC via a standard interface such as universal serial bus (USB) that will enable enhanced voice and data services. The SWAP also can use the connection point to support power management for prolonged battery life by scheduling device wakeup and polling (http://www.homerf.com).

• X10—This is a communications protocol for remote control of electrical devices and communications over standard household AC powerline wiring (off, on, and dim functions).

• IEEE 1394—This is a serial interface for short-range, low-data-rate, infrared communications between entertainment and computer devices.

• Home Phoneline Networking Association (HomePNA)—Home phoneline–networking technologies must tolerate completely random and unspecified wiring topologies. They must also be designed to take into consideration the unknown but typically large degree of signal attenuation that occurs within the random tree network topology. A transmitted pulse is attenuated and scattered on the wires as it bounces around inside the wiring. The longer the pulse travels through the wire mesh inside the house, the more it attenuates and dissipates. Home phoneline–networking technologies require high and varying levels of signal noise and must tolerate dynamically changing transmission line characteristics, while coexisting with telephone service and complying with Federal Communications Commission (FCC) Part 68. Lastly, they must maximize data throughput given the above constraints and limitations (http://www.homepna.org).

• HWN SSERQ/AAWG—Superspread equilateral reservation queueing (SSERQ) protocol is optimized for wireless transport of voice, data, and multimedia services. Its packet-reservation scheme provides the high QoS and access priority required for voice and multimedia services. Wideband, common-channel signaling permits rapid setup and takedown of virtual private circuits for high-speed intranet traffic and Internet access. SSERQ supports IEEE–802.11 infrastructure-mode (client/server) networking via the air-to-air (air-squared) wireless gateway, which provides translation, supervision, and transport between 802.11 and SSERQ networks (http://www.homewireless.com).