The project A2Bit aims to analyse how fundamental principles and techniques of virtual currencies such as Bitcoin can successfully be applied to other problem domains which also demand a comparable level of security, for example identity management and public key exchange.
The Bitcoin protocol has shown that a decentralized Peer-to-Peer (P2P) currency is technically possible today. Such a cryptocurrency has to fulfil several security properties to mitigate all kinds of attacks like double spending, denial-of-service, malicious clients, man-in-the-middle and so forth. Bitcoin protects against these common attacks and offers an answer to the Byzantine Generals’ problem by providing a computational proof of the majority consensus in its distributed network. Since other internet protocols are facing similar threats, it is a logic consequence to investigate into methods to apply the successful mitigation strategies of Bitcoin to other problem domains. The A2Bit project aims to tackle this research challenge by generalising the Bitcoin protocol for trustworthy key-value stores. A distributed key-value store based on the Bitcoin protocol would have several applications which would considerably improve secure online communication. An entry in the distributed key-value store can be an arbitrary key-value pair. The value for example can be a mapping of a domain name to an IP address including a HTTPS certificate, a GPG/PGP public key or a small encrypted file including private passwords. Therefore, it could serve as a public key exchange, identity management platform, time-stamping service, twitter clone or alternative domain name system. Such an infrastructure would pose a significant security benefit, since it provides a way to securely distribute and publish small amounts of information. Although Bitcoin laid the groundwork for such an idea, there are still many open questions and obstacles to overcome. Current designs like Namecoin, which aims at a likewise direction, lack a consistent attacker-, mathematical- and scalability model. Additionally, the performance of the Bitcoin protocol as well as the structure of its P2P network is still topic of ongoing research.
The A2Bit project will substantially improve the knowledge on how to apply approaches from the domain of virtual currencies to other related areas which require comparable security properties. We focus on the generalized concept and design a trustworthy distributed key-value store. Thereby, we determine the potential as well as the limitations of this technology.
In detail we will (1) create consistent attacker models for a distributed key-value store (2) lay the mathematical groundwork to define the feasibility and scalability of such an approach, and (3) provide methods to construct optimized key-value stores depending on their use case.