Up to eight devices can be included in a single piconet. Many of the devices that participate in Bluetooth communications are small and intended to be portable. With one of the major considerations in portable device weight being power consumption, the system has been designed to operate using only small amounts of power. Up to three users can participate on a piconet at any one time. Data transport can operate in either symmetric or asymmetric modes.
Cost is an extremely important factor.
Given that the Bluetooth interface is intended to be included in many consumer devices, one of the keys to its success will be the fact that it is inexpensive. This has been a concerted effort on the part of several companies to develop a set of standards that can meet the needs of a broad range of users. One of the important lessons that the Bluetooth SIG has learned is that there's not much point in reinventing the wheel. The Bluetooth SIG has defined the specific protocols necessary to provide the link services, service discovery, and link management germane to the specific RF interface. The full suite of protocols included in the Bluetooth domain is shown in Figure 1 .