Enabling off-the-grid communication for existing applications: A case study of email access

Most of today's applications require an Internet connection to reach cloud servers essential for their functioning. However, in many scenarios, such connectivity is unavailable, such as when a user is in a remote location with no cellular coverage or during a natural disaster. In these situations, nearby devices can still connect to each other, and the applications running on each device can have data useful to each other; however, the applications are unable to exchange data directly between themselves. In this paper, we describe mechanisms to enable off-the- grid communication for existing applications, allowing them to directly exchange data between themselves. To achieve this goal, an application should be capable of discovering, fetching, and verifying data without the help of a server. We believe that Named Data Networking (NDN) can provide an application with these abilities. We utilize email access as a study case and propose mailSync, a framework to the goal of app-to-app communication for this application via NDN. Meanwhile, we identify the various differences between TCP/IP and NDN applications, and we generalize several steps to «NDNize» an existing application, including protocol translation, application layer framing, naming, data discovery and security management. We implemented a prototype of mailSync in Java on laptop and Android as a proof of concept.