The virtual device: expanding wireless communication services through service discovery and session mobility

We present a location-based, ubiquitous service architecture, based on the session initiation protocol (SIP) and a service discovery protocol that enables users to enhance the multimedia communications services available on their mobile devices by discovering other local devices, and including them in their active sessions, creating a "virtual device." We have implemented our concept based on Columbia University's multimedia environment and we show its feasibility by a performance analysis.