The dynamic composition of networked appliances, or virtual devices, enables users to generate complex, strong, and specific systems. Current MANET-based composition schemes use service discovery mechanisms that depend on periodic service advertising by controlled broadcast, resulting in the unnecessary depletion of node resources. The assumption that, once generated, a virtual device is to remain static is false; the device should gracefully degrade and upgrade along with the conditions in the user's environment, particularly the network's current performance requirements. Presently, schemes for infrastructure-less virtual device composition and management do not consider this adaptation. We present a distributed constraint satisfaction problem (distCSP) for virtual device composition in MANETs that addresses these issues together with simulations that show its effectiveness and efficiency.

The proliferation of networked appliances or dedicated function consumer devices with embedded processors and network connection capabilities is driving the virtual device concept, whereby such appliances can be controlled, monitored, managed, and extended beyond what they were initially designed to do. The dynamic and ad hoc nature of the discovery and composition of such devices and the services they provide inevitably leads to capability differences, whereby the input of a service B is not compatible with the output of a service A; A and B needing to be composed. Moreover, current schemes for service composition in MANETs do not consider capability differences. We present a distributed constraint satisfaction problem for capability reconciliation in MANETs, and through simulation show its effectiveness and efficiency.

The dynamic composition of systems of networked appliances, or virtual devices, enables users to generate complex strong specific systems. Current prominent MANET-based composition schemes make use of service discovery mechanisms dependent on periodic service advertising by controlled broadcast, resulting in the unnecessary depletion of node resources (i.e. battery and processing power). Moreover, current schemes do not allow for the protection of private or security sensitive information in the process of composition. We present a distributed constraint satisfaction problem for virtual device composition in MANETs addressing these issues, and through simulation show its high efficiency and QoS-awareness.

The dynamic composition of systems of networked appliances, or virtual devices, in MANETs, enables users to generate, on-the-fly, complex strong specific systems. Current work in the development of service composition architectures in MANETs has yet to address QoS metrics for enhanced composition from a virtual device perspective. In this paper, we present an extension to a prominent dynamic broker-based distributed service composition protocol, embedding in a distributed manner, a QoS model providing compositions that form the best possible virtual device at the time of need. Simulation results show that our protocol extension provides a high increase in QoS at a low cost in terms of increased amounts of messages and composition time.

AmbiTalk is a ubiquitous system based on the session initiation protocol (SIP) and Bluetooth that allows a mobile device to automatically adapt the behavior of its communication services as its user moves from one location to another. The adaptation is policy-based and occurs both pre-call and mid-call. We present the AmbiTalk architecture and discuss how it allows a device to automatically adapt its communication properties to its current environment and other devices. We demonstrate the viability of the AmbiTalk approach with the implementation of a prototype