ABSTRACT
Ubiquitous computing (ubicomp) strives at creating a completely new paradigm of computing environment in almost all of these respects. Ubicomp systems aim for a heterogeneous set of devices, including invisible computers embedded in everyday objects such as cars and furniture, mobile devices such as personal digital assistants (PDAs) and smart phones, personal devices such as laptops, and very large devices such as wall-sized displays and tabletop computers situated in the environments and buildings we inhabit. All these devices have dierent operating systems, networking interfaces, input capabilities, and displays. Some are designed for end user interaction-such as a public display in a cafeteria area-whereas other devices, such as sensors, are not used directly by end users. e interaction mode goes beyond the oneto-one model prevalent for PCs, to a many-to-many model where the same person uses multiple devices, and several persons may use the same device. Interaction may be implicit, invisible, or through sensing natural interactions such as speech, gesture, or presence: a wide range of sensors is required, both sensors built into the devices as well as sensors embedded in the environment. Location tracking devices, cameras, and three-dimensional (3-D) accelerometers can be used to detect who is in a place and deduce what they are doing. is information may be used to provide the user with information relevant in a specic location or help them adapt their device to a local environment or the local environment to them. Networking is oen wireless and ad hoc in the sense that many devices come in contact with each other spontaneously and communicate to establish services, when they depart, the network setup changes for both the device and the environment.
