Creating content in the digital era has never beenso easy. However, there exists no framework inwhich artists can share, cooperate and transferuniversal content. We refer to the termuniversalas that allowing our architecture to manage contentboth from the physical and digital world. Currentplatforms are either centralized and sector-specificsuch as Netflix and Spotify, or decentralized.On the one hand, the centralized platforms havecontrol over both the data and the identity of theirusers. On the other hand, decentralized platformslack scalability and an identity layer. Our architec-ture expands current decentralized solutions witha more scalable and generic framework. This so-lution allows users, and their verified identities, topossess control over their data; share and exchangecontent, both from the physical and digital world;and get attribution and royalties for their work inany digital coin.

Digital identity management has been established in a mainly centralized manner. In response to a lack of control in current identity management systems, the concept of Self-Sovereign Identity (SSI) was defined to enable decentralization. Recently, this concept gained traction, and several implementations have been proposed. The decentralized nature of blockchain technology was combined with the concept of SSI. However, no critical review on the privacy protection of this technology in combination with SSI currently exists. This research evaluates current blockchain-based SSI implementations in the lights of privacy protection. It proposes a model for determining the privacy protection that specific solutions can offer based on defined criteria. The technology to be able to satisfy these privacy criteria in blockchain-based SSI is available. However, the evaluation shows that most implementations do not satisfy all privacy criteria, of which some even score poorly on privacy protection.

Self-sovereign identity (SSI) provides users of the internet control over their own data by letting them store it on their own device or in a decentralized way, such as on a blockchain. The Super App is an SSI application currently under development by the Delft Blockchain Lab, but it still lacks one of the core features of SSI, which is interoperability. In SSI applications, the user will be in control over their identity when an issuer attests to it. Services can request confirmation about the identity of a user through a verifiable claim, to which the user can reply with this attestation. This research first focuses on building a claim portability framework, which means these verifiable claims and attestations can be communicated between the Super App and other applications. This framework is designed using a public key infrastructure, as that is already present in the Super App. Before sending a claim or attestation, it is signed by the sender and encrypted with the public key of the intended receiver for security purposes. The Super App currently lacks infrastructure to assign issuers of attestations, so a Trusted Issuer registry will have to be stored somewhere in the network. To contest the adoption problem that currently exists in many SSI solutions, the usability has been evaluated as it plays a significant part in adoption. For this, some mock-up user interfaces were created and evaluated by users through a survey and some suggestions were made for improvements.

Decentralized Finance (DeFi) is build on smart-contract supporting blockchains, with Ethereum being the largest ecosystem. A collection of smart-contracts aims to serve as decentralized implementations of financial systems. The philosophy of DeFi dictates automation and desintermediation through exploiting nascent distributed ledger technology and cryptoanarchist ideologies. Interest in DeFi has risen in the past year, with total value locked in Ethereum based decentralized applications having multiplied fiftyfold. Lending is one of the main building blocks of finance and DeFi protocols try to provide that service. Lending services offer liquidity in exchange for counterparty guarantee. Due to the pseudonymous nature of DeFi that guarantee is limited to collateral, which is expressed in overcollateralization as a result of cryptomarket volatility. A persistent, untamperable and uniquely identifiable credit history opens the door for counterparty guarantee without liquid collateral. Uncollateralized lending lowers a barrier of entry for mainstream adoption of Decentralized Finance. This paper proposes a novel solution to cryptographically secured loans in a decentralized system by presenting a credit history linked to a persistent self-sovereign identity.

As the amount of digital content being shared is increasing, the need for a privacy protecting and resilient method of file sharing grows. New copyright law proposals are suggesting that governments and corporations are attempting to claim control over the use of the internet. As these new laws may lead to restrictions in digital content sharing, as well as endangering the privacy of users, alternative methods of sharing files may be able to solve these issues. Peer-to-peer networks for file sharing, such as BitTorrent, are resilient networks due to their decentralised nature. Tribler combines the BitTorrent protocol with a Tor-like anonymity system to protect its users against governments and spooks. Due to its Tor-like onion routing protocol, exit nodes are important for a robust network. This project focuses on PlebNet, an autonomous self-replicating network of Tribler exit nodes. Using Cloudomate, PlebNet is able to purchase servers with Bitcoins acquired from selling Tribler’s bandwidth tokens and replicate itself to expand its network of exit nodes.