Application of NAT-traversal Techniques to Decentralized Cloud Storage

The Information-Communication Technolgies (ICT) world is heading towards an increasingly interconnected network of Internet of Things (IoT) devices. In this scenario is of particular importance to provide techniques which can simplify the direct communication of devices over a wide area network. These techniques include methods to traverse so-called Network Address Translators (NAT) since they restrict the end-to-end principle of the first Internet’s design. With this background, this work aims to collect all the state of the art techniques to connect devices directly and to describe each of them giving pro and cons. To better provide an example of how important these solutions are nowadays, some of them have also been implemented and described in a real- world project: Cubbit. Cubbit is a distributed cloud service which leverage on a swarm of interconnected IoT devices to provide a fast, reliable and secure cloud storage platform. To do so, the software splits, encrypts and spreads the files across the network to make them retrievable later. Because of its peer-to-peer nature, the project is also subject to the connectivity issues caused by NATs, and it has been a perfect playground to explore the described techniques practically.