On Interaction Model for Network Spatial Proximity Services

In this paper, we present a connectionless interaction model for network spatial proximity services. In the network spatial proximity model, the reception of an identification or discovery frame of a nearby wireless node confirms proximity and delivers content at the same time. Current Bluetooth and Wi-Fi specifications and mobile platforms extend this one-way announcement with responses, addressed messages, scheduled group exchange, and relaying, which still do not require a connection. The proposed model describes such interaction independently of a concrete wireless technology. It is based on the roles of nearby nodes, the proximity message as the unit of interaction, twelve pattern properties, and six interaction patterns: announcement, mutual announcement, query-response, addressed exchange, scheduled group exchange, and relay. An exit rule defines when a service should move to a connection-based channel. We analyze how the patterns can be implemented on Android and iOS smartphones through native mechanisms, substitution, composition, embedded bridges, or a step-up to a connection, and we propose a pattern selection method for developers. The model generalizes the earlier network spatial proximity model and refines the interaction primitives of the proximity core. It is illustrated by existing services and systems and supported by published measurements and first-order estimates. - A Connectionless Interaction Model for Network Spatial Proximity Services