Veritaa - The Graph of Trust

Today the integrity of digital documents and the authenticity of their origin is often hard to verify. Existing Public Key Infrastructures (PKIs) are capable of certifying digital identities but do not provide solutions to immutably store signatures, and the process of certification is often not transparent. In this work we propose Veritaa, a Distributed Public Key Infrastructure and Signature Store (DPKISS). The major innovation of Veritaa is the Graph of Trust, a directed graph that uses relations between identity claims to certify the identities and stores signed relations to digital document identifiers. The distributed architecture of Veritaa and the Graph of Trust enables a transparent certification process. To ensure non-repudiation and immutability of all actions that have been signed on the Graph of Trust, an application specific Distributed Ledger Technology (DLT) is used as secure storage. In this work a reference implementation of the proposed architecture was designed and implemented. Furthermore, a testbed was created and used for the evaluation of Veritaa. The evaluation of Veritaa shows the benefits and the high performance of the proposed architecture.