Infrastructure-less Group Data Sharing using Smart Devices

Abstract

Advances in pervasive communication technology have enabled many unconventional applications that facilitate and improve the safety and quality of life in modern societies. Among emerging applications is situational awareness where individuals and first-responders receive timely alerts about serious events. Another example is exchanging road conditions between vehicles in a peer-to-peer fashion. The increasing popularity of smart devices and their support for multiple device-to-device (D2D) communication standards have made them an attractive choice for realizing these emerging applications. However, most existing protocols for data sharing among smart devices either require an internet connection, which may not be available, could incur extra costs, or suffer from the device?s operating system limitations. Moreover, there is no existing solution that allows a set of devices to start sharing data dynamically without forcing users to apply an elaborate procedure for setting up a group. These shortcomings render existing solutions unsuitable for emergency cases and highly dynamic applications. In this dissertation, we fill such a technical gap and present a framework for enabling an infrastructure-less data exchange in a cost-effective and timely manner through the establishment of peer-to-peer links among smart devices. In addition, our framework opts to minimize the required user interaction for setting up a connection. Our framework consists of a suite of protocols for data exchange using Wi-Fi Direct. First we present a protocol for Alert Dissemination using Service discovery (ADS) in Wi-Fi Direct that is suitable for short messages. ADS uses the service discovery feature of Wi-Fi Direct for distributing its data in a connectionless manner, thus avoiding the setup delay in creating Wi-Fi Direct groups. In addition, we present an Efficient and Lightweight protocol for peer-to-peer Networking of smart devices over Wi-Fi Direct (ELN) that is suitable for sharing large amounts of data between a group of users. ELN mainly provides a group management solution that allows dynamic memberships and adapts for topology changes. Finally, we present an Efficient Multi-group formation and Communication (EMC) protocol for Wi-Fi Direct that is suitable for sharing data between many users distributed along a wide area, which cannot be covered by one group. EMC allows potential group owners to be qualified based on certain criteria and enable dynamic formation of groups. Moreover, EMC allows data exchange between different Wi-Fi Direct groups. To support the implementation of EMC in Android, we have developed an IP Subnet Negotiation Protocol for Seamless Multi-Group Communications (ISNP). ISNP overcomes a limitation of Android?s Wi-Fi Direct implementation that forces all the formed groups to share the same range of IP addresses. All the proposed protocols have been validated through implementation on actual Android devices. In addition, the performance of our framework in large setups is studied through simulation, where a library for Wi-Fi Direct and our protocols has been developed and added to OMNet++. To the best of our knowledge, our framework is the first comprehensive peer-to-peer solution for mobile devices that takes advantage of the capabilities of Wi-Fi Direct.