# Blockchain Technology and Its Potential to Benefit Public Services Provision: A Short Survey
## 1 Introduction  
Blockchain is a distributed ledger technology (DLT), which relies on the computing primitives of cryptography and digital signatures. Each user who participates in the blockchain is uniquely identified by an address derived from his/her public key. The distinctive element of this technology is the absence of a central authority, meaning that transactions are stored by all users connected to the network. As the name suggests, a blockchain can be thought of as a chain of blocks. Each block contains three types of information: data (about the transaction being carried out), a hash code, which uniquely identifies the transaction, and the hash code of the previous block. In order for a block to be added to the chain, it has to be approved by the majority of validator nodes, who must reach a consensus on the integrity of all transactions within the block. Due to the strong computational and mathematical backbone, blockchain technology stands out for being immutable (once a transaction is added to the blockchain it cannot be further modified), transparent (it has a distributed nature, meaning that each participant has a full copy of the ledger), traceable (it is possible to reconstruct the history of all transactions), efficient (it lacks a central authority as peers work together to validate transactions), and reliable (thanks to the encryption of transactional data). These distinctive features make blockchain technology suitable for use cases and applications that range across a variety of domains (see, e.g., [1,2] for an overview), including the ones where confidentiality of sensitive information is paramount. Ensuring the confidentiality of sensitive information within blockchain technology necessitates the deployment, as anticipated, of sophisticatedcryptographic methods and stringent access control protocols. Notably, the usage of asymmetric encryption, where each participant is equipped with a pair of cryptographic keys: a public key for general dissemination and a private key kept confidential. Transactions are encrypted using the recipient's public key, ensuring that only the corresponding private key can decrypt the data, thereby safeguarding unauthorized access. Hashing algorithms play a critical role in preserving data confidentiality by transforming sensitive information into fixed-size hash values, which are then stored on the blockchain. This ensures data integrity while making it infeasible to reverse-engineer the original information from the hash. Employing permissioned blockchains adds another layer of security by limiting network access to verified and trusted participants only, thus preventing unauthorized entities from joining. Public services provision is one of the main sectors that is likely to benefit from its adoption, as evidenced by the growing number of successful implementations. Blockchain could be used as a tool to ensure the integrity of procedures and administrative accessions, reducing fraud and errors while enhancing transparency, traceability, people's trust in processes, and improving public service delivery in terms of productivity and effectiveness, aspects which tend to alter the trust of citizens and stakeholders towards public services [3; 4]. In this survey, we are not interested in the cryptocurrency side of the blockchain, nor in its technological implementations, for which we refer the interested reader to landmark resources such as [5; 6]. Rather, we focus on blockchain technology as the main driver for the digital transformation of government infrastructure (both at the state and local levels) and discovering the applications and domains within the public services umbrella that can benefit from blockchain technology. We argue that the usage of blockchain technology within public services can foster the concept of servitization from a mere industrial perspective [7] to a more comprehensive public services perspective, where public administration is seen as a service provider to citizens.