Opportunistic Beacon Networks

Modern society is surrounded by an ample spectrum of personal mobile devices with short-range wireless communication support. This ubiquity creates an immense potential of new concepts for people-centric ad hoc networks that can be applied to every personal and social dimension of life. The last decade introduced the concept of Opportunistic Networks (OppNets) that facilitates delay-tolerant information sharing between mobile users anytime, anywhere, and every which way possible. OppNets constitute an appealing solution to provide connectivity in those situations where communication is desired, but situated network architectures fail to provide it effectively. Despite the mobile revolution that the world is relishing today, the support of modern wireless technology in smart mobile devices is quite limited to fulfill OppNet services. While having promising potentials, the current wireless standards (e.g. Wi-Fi, Bluetooth) have restricted or hidden support for ad hoc communications in mobile operating systems. So far, such limitations have stimulated little research efforts to devise an alternative solution for the realization of OppNets. Besides, these standards are designed to achieve ad hoc communications under stable connectivity, therefore cannot cope with the highly-dynamic characteristics of OppNets. Intrinsically, OppNets rely on mobility of users to extend the dimension of communications over large distances. By and large, the mobility assistance greatly needed by OppNets requires innovative design considerations for the networks of smart mobile devices. This thesis focuses on the design, implementation, and analysis of a novel OppNet architecture intended for smart mobile platforms. Named Cocoon (Community-oriented Context-aware Opportunistic Networking), this architecture assists the practical development of a wide range of OppNet applications offered for general public use. Cocoon integrates versatile and lightweight opportunistic communication methods with a new collection of applications which are freely accessible by any group of mobile users. The presented applications span a rich collection of applications, such as short message services in challenged environments, safety monitoring in vehicular environments, and data dissemination in several demanding scenarios. In order to carry out these applications, Cocoon introduces a versatile and lightweight connectivity scheme, called opportunistic beacons, that expedites rapid and energy-efficient information sharing between smart mobile devices without requiring connections and sophisticated configurations. The design of opportunistic beacons is generic, so that it is readily integrable on top of the commonly-used wireless interfaces such as Wi-Fi and Bluetooth. The Cocoon architecture employs opportunistic beacons in the design and management of networking and application services. As a networking service, Opportunistic Beacon Networking (OBN) is introduced. Within OBN, a forwarding protocol is proposed and validated with extensive real-world experiments. The protocol is mainly offered for data dissemination purposes, but its end-to-end multi-hop routing performance has been evaluated as well. Furthermore, several improvements are presented, implemented, and compared for this protocol. For application management, a new set of service requirements are defined in view of the ever-changing nature of OppNets. These requirements are used in a distributed decision-making algorithm running alongside with OBN. The basic aim of the algorithm is to provide a quality-of-service to participating users by scheduling applications on their affiliated devices. The OppNet applications presented in this thesis are quite promising considering their performance outcomes. To effortlessly and efficiently develop such applications, the Cocoon architecture can also be used as a development platform to realize opportunistic communications. To this respect, this thesis further provides an application programming interface guide on Android (Cocoon API) and a verified simulator on MATLAB/Octave that can be used to develop and analyze Cocoon-based networks.