Custom cloud storage solutions based on Nextcloud: a case study implementation

Nowadays, the world is characterized by a rising and relentless production and consumption of information, be it related to the private life of people or to aspects concerning businesses, industries, organizations, and Nations. Globalization demands information to be available always and anywhere. The constant availability of information is at the very core of a concept known as business-continuity which, however, can also be applied to the private dimension of our lives, since today most of the information we make use of is not really under our control, rather, it is stored somewhere around the world. Making data always available for people, independently from their geographic location, from the device they are using, and from many other parameters, is not a simple task. Most companies and organizations do not have the budget and the technical knowledge to fulfill such a task on their own, which is why they buy services from providers offering data storage solutions based on the `Cloud Paradigm`. Cloud storage services provided by vendors such as Dropbox, Google, Amazon, Microsoft, Apple, etc. are extremely popular among private users, companies, and organizations; however, they all have common problems: data security and data sovereignty. It is not always possible, in fact, to precisely determine where data are physically stored (i.e., even if the provider is GDPR-compliant); moreover, information about the cybersecurity policies and procedures adopted by providers are not usually very detailed. These issues concern anyone, but they are clearly more important for actors dealing with confidential data which might have an impact on the safety and security of people and other valuable assets. There exists, therefore, a space for designing and implementing cloud storage solutions that give customers and users a greater control over their data. The aim of this thesis is to investigate the design and development of cloud storage solutions capable of giving users a complete control of the data and of the underlying infrastructures including, for instance, how data are managed and protected. With respect to this goal, open-source cloud storage platforms represent an ideal starting point being inexpensive, highly customizable, and open to anybody's contribution for improvement. The open-source cloud storage platform chosen for this thesis is Nextcloud, which is probably the most popular solution in its category. Starting from an implementation based on a very simple infrastructure, this thesis investigates the deployment of Nextcloud according to multiple strategies, such as purely on-premise, purely remote, and hybrid ones. Issues such as confidentiality, integrity, authentication, authorization, and physical control of data have been taken into account during the analysis, also considering the native features provided by Nextcloud. In conclusion, this thesis discusses the possibility of implementing a secure, highly-customized cloud storage platform based on open-source software that is capable of competing with, and even surpassing, commercial solutions available on the market.