The word blockchain is often used more as a buzzword than a specific description of a technology. This usually leads to incorrect applications of BCT to projects usually disconnected from the real BC capabilities. A formal and scientific understanding of BCT represents the primal step to correctly apply BCT on real-use cases. In this track, we methodically discuss the most relevant BCT from an academic perspective, highlighting how they should be applied in several industrial scenarios.

Furthermore, we investigate new blockchain protocols in order to tackle some of the most important open problems in the area: speed of transactions, security of transactions and privacy of the protocol. This will provide a better understanding of the current limitations of BCT, and possible techniques to overcome them.

Finally, we will investigate and develop new tools to overcome well-known limitations of current BCT such as transactions speed, transaction security and privacy, portability of the protocols. These new instruments will be integrated into ad-hoc blockchain protocols specifically designed (and developed) for real-world applications. Specific experiments will allow testing the improvements obtained by our newly implemented protocols.

We strongly recommend a high level of abstraction for those candidates applying to this ESR.

As blockchain technologies are more and more leveraged to build-up distributed applications, the belief spreads that they are going to become a building block for digital communication in the IoT. The blockchain has a number of properties, such as anonymity and non-modifiability of data, that can be exploited for malicious activities. Therefore, it is of paramount importance to investigate how such technologies can be used to deploy malicious code or to infect other nodes in the network as well as to design new defense techniques to mitigate them. However, not much is known with regard to the security of communications in the relative peer-to-peer networks. For example, nothing has been done to investigate the blockchain as an infection vector. The possibilities of attacks involving the blockchain are manifold. Firstly, the blockchain itself can be attacked in order to corrupt the data contained in it or to insert invalid data. This is the case of the well-known 51% attack, where an attacker is able to prevent new transactions or even to reverse old transactions inserted during the attack, thus allowing double-spending. Similar results can be obtained with the Eclipse attack, where an attacker misleads a node’s communications to bias its behavior and compromise the consensus system. Secondly, the blockchain can be used as a tool for carrying out attacks to other entities. A typical example is that of the blockchain used for the communications between the nodes of a botnet and their command-and-control (C&C) server, thus preventing the common countermeasures currently adopted. Finally, the blockchain can be used as a vector to infect the nodes participating in its own peer-to-peer network with some malicious code. This is a still unexplored field that needs special attention because of its great potential dangerousness. As such, there is the need of exploring the security aspects of blockchain-based networks, in order to understand if the existing monitoring and defense techniques are still applicable or not.

We strongly recommend strong programming skills for those candidates applying to this ESR.

In the last few years, different blockchain applications have been designed and developed. While the share some building blocks such as the broadcast peer-to-peer protocol or the transaction timestamping approach, they also have different schemes as regards the mining algorithm being used or the fault resiliency provided. With smart contracts, this became even worse as they allow the creation of customized virtual functions that are executed and validated by everybody in the network during the mining phase. This means that, depending on the network protocol, the smart contract developing language and the mining algorithm being used, similar blockchain might suffer from different security holes. As such, the design of ad-hoc auditing and monitoring systems might not work any longer in the blockchain ecosystem. This ESR will then design an advanced, automated and universal auditing system that can be used to verify the presence of known security holes within a blockchain-based application as well as to predict new vulnerabilities based on artificial intelligence and machine learning tools.

We strongly recommend strong programming skills for those candidates applying to this ESR.

Deployed blockchains are real-world systems. They encompass circumstances that go beyond the mere technical aspects of their architecture and foreseen use. These factors can be somewhat anticipated, based on the designer’s insights and expected stakeholder behavior, but only to a certain extent. Any deviation in real-world conditions (economic, legal, social, etc.) on which the system relies will have an impact on its behavior and properties, such as its security, its mass adoption, or its economic viability.
For instance, Bitcoin’s seminal distributed ledger mechanism encourages membership in the network by rewarding the participation in the distributed agreement protocol by “mining”. In turn, membership in increases the strength of the ledger against malicious subversion, but only so long as no single entity controls a too large fraction of the deployed computing power. The emergence of centralized mining operations and the hoarding by few users of most currency units to bank on future value gains were not foreseen in the original vision. Thus, an idealized view of a system where all the users were also miners and stakeholders soon collided with the reality of an oligopolistic system with few dominant players.
The consequences of economic considerations in distributed system design are stark.  In recent days, Bitcoin is being rendered unusable by exorbitant transaction fees and dismal transaction speed and rates. The root of the issue lies with blockchain block size: the original Bitcoin design consciously neglected to specify a firm growth schedule in block size, leaving the community and the software maintainers with the responsibility to agree on technical measures that would solve emerging issues. But growing adoption and enormous financial stakes in play turned consensus-building regarding software updates a huge political challenge where the majority mining stakeholders resist change. The resulting standstill easily backfires, undermining the viability of the system they would like to defend.
Our economic and legal analysis aims to model and capture and make sense of these external factors’ effect on the design of a real-world BCT by modeling the external constraints a BCT system is subject to.

We strongly recommend a high level of abstraction as well as an economic background  for those candidates applying to this ESR.