Smart contracts on the blockchain – A bibliometric analysis and review

Smart Contracts on the Blockchain – A Bibliometric Analysis and Review

Since Friedrich Kessler wrote “Contracts of Adhesion-Some Thoughts About Freedom of Contract” in 1943, condemning narrow adherence to the principle of “freedom to contract” in the face of large scale enterprises’ growing preference for standard form contracts, Courts have balanced their desire to uphold contracts while protecting weaker parties from adhesion. Today, they face similar challenges with the rise of code-driven smart contracts and blockchain governance. Similar to Kessler’s world, where standard-form contracts were a tool for “excluding or controlling the ‘irrational factor’ in litigation” such as uncertain outcomes of judicial interpretation, automated smart contracts aim to put themselves outside the control of both contractual parties and the courts, thus removing any ability to breach or tamper with the original terms. Smart contract advocates contend that removing the judiciary as the governing body over contract law and imposing contractual performance via decentralized blockchain governance improves efficiency and certainty.
 But, how much can one really write a contract that completely circumvents the potential for legal intervention or judicial enforcement? Will smart contracts finally achieve the complete separation between private and public law that advocates of “freedom to contract” originally claimed, or does the common law legal system’s deep-rooted belief in the rule of law and due process prevent the judiciary from being excluded from contract enforcement regardless the medium? And is there a risk that, as smart contract sceptics posit, smart contract platforms and blockchain governance create a new feudal order with a “potentially illegitimate exercise of power” and “normatively suspect” wealth distributions?
 The short answer, as this paper will demonstrate, is that as long as smart contracts meet the traditional requirements of a contract, they cannot fall outside the establish legal system’s purview. The only thing a smart contract truly adds to traditional contracts is automated execution that is enforced by the blockchain’s consensus mechanism; this may provide some efficiency to the legal system by streamlining basic performance but it cannot be the only form of governance over smart contracts. While there may be procedural challenges to undoing or enforcing specific performance under smart contracts because of their decentralized features, any substantive problems that could occur within a smart contract are imminently addressable with and must be subjected to the principles and remedies found in traditional contract law. Finally, I will conclude with current developments in smart contracts which point to a potential for them to become an integral part of our legal system going forward. Overall, I will argue that smart contracts, if carefully drafted to consider potential pitfalls and the future needs of contracting parties to amend or enforce, can hold the potential to provide efficiencies and greater legal certainty to contracting parties. This is achieved, not through circumventing the legal system, but by working with it to automate simple performance enforcement and deferring more complex contractual breakdowns to the judiciary.

Purpose – Smart contracts minimise transaction costs and boost efficiency. Smart contracts are costly, single-use, and inefficient. This study proposes a smart contract mechanism to address these issues. Design/methodology/approach – This study examines smart contract research history, models, and platforms to highlight their flaws. Based on typical contract content, a smart contracts model is built. Findings – This paper describes smart contract operation using several models. Decomposing smart contracts into sub-contracts facilitates global implementation. Then, smart contract benefits and deployment strategies are examined. Here's an illustration of how smart contracts will affect our lives. Originality/value – Smart contract is expanding. This article describes smart contract structure and functioning. Keywords: AI, 4th IR, Applicability, international law, Smart contracts.

Interpretation of a legal agreement can be done by taking the internal and actual intention of the parties as a starting point (objective), or by taking the expression of those parties as a starting point (subjective). The legal systems under consideration here all pay attention to both objective and subjective criteria, yet differ in their details and nuances. In light of the fact that smart contracts might result in binding legal agreements, the impact of the technology on such interpretation regimes must be considered. First the nature of smart contracts must be considered. Smart contracts provide a take-it-or-leave-it offer to an offeree. Combined with the fact that the platform on which such smart contracts exist are pseudonymous, this means that the offeree is not a position to negotiate. For this reason, strong parallels can be drawn with standard form agreements. Standard form agreements are regulated on a European level in all legal systems in scope through the Unfair Contract Terms Directive. It is argued that the instruments contained in this Directive should be applied to smart contracts in situations in which a potential for a power discrepancy between the offeror and the offeree exists. In situations in which no such power discrepancy exists, the national rules on interpretation should apply. Whilst the previous chapter has shown that smart contracts might contain an expression of intent, and therefore might result in a binding legal agreement, this does create problems of interpretation. Unclear might be, for example, whether (and how) such regimes of interpretation should be applied to code, to natural language, or perhaps to both. Moreover, relevant questions are whether additional circumstances that are relevant in the interpretation of an agreement might surface on a smart contract platform and whether such circumstances can be considered when interpreting an agreement. This chapter presents a taxonomy of smart contracts that consists of four scenarios. In the first scenario the smart contract in and of itself is the legal agreement. In the second scenario there is a smart contract, but there is no accompanying legal agreement; the smart contract is mere code and the transfer is a mere transaction. The second scenario is unique in that there is no legal agreement whatsoever. In the third scenario the smart contract is accompanied by a legal agreement, but is separate thereof. In that case the smart contract is a tool to execute the legal agreement. Lastly, in the fourth scenario the smart contract and the accompanying legal agreement are merged.

As blockchain technology advances, so has the deployment of smart contracts on blockchain platforms, making it exceedingly challenging for users to explicitly identify application services. Unlike traditional contracts, smart contracts are not written in a natural language, making it difficult to determine their provenance. Automatic classification of smart contracts offers blockchain users keyword-based contract queries and a streamlined effective management of smart contracts. In addition, the advancement in smart contracts is accompanied by security challenges, which are generally caused by domain-specific security breaches in smart contract implementation. The development of secure and reliable smart contracts can be extremely challenging due to domain-specific vulnerabilities and constraints associated with various business logics. Accordingly, contract classification based on the application domain and the transaction context offers greater insight into the syntactic and semantic properties of that class. However, despite initial attempts at classifying Ethereum smart contracts, there has been no research on the identification of smart contracts deployed in transactive energy systems for energy exchange purposes. In this article, in response to the widely recognized prospects of blockchain-enabled smart contracts towards an economical and transparent energy sector, we propose a methodology for the detection and analysis of energy smart contracts. First, smart contracts are parsed by transforming code elements into vectors that encapsulate the semantic and syntactic characteristics of each term. This generates a corpus of annotated text as a balanced, representative collection of terms in energy contracts. The use of a domain corpus builder as an embedding layer to annotate energy smart contracts in conjunction with machine learning models results in a classification accuracy of 98.34%. Subsequently, a source code analysis scheme is applied to identified energy contracts to uncover patterns in code segment distribution, predominant adoption of certain functions, and recurring contracts across the Ethereum network.

Blockchain smart contracts formalization: Approaches and challenges to address vulnerabilities

Fabric is currently the most popular consortium chain platform with a modular architecture that provides high security, elasticity, flexibility and scalability. Smart contracts realize the automatic execution of transactions and the operation of reconciliation data. The Fabric platform supports general programming languages ​​to write smart contracts. However, in the development process of smart contracts, due to insufficient understanding of the underlying operating logic of smart contracts, developers are prone to introduce some risky operations, resulting in a mismatch between the execution logic of smart contracts and business logic, resulting in a lot of losses. The read-after-write risk is a relatively complex and common security risk in smart contracts. Currently, many detection tools cannot detect this risk. There is an urgent need for a solution that can quickly and accurately detect the read-after-write risk in smart contracts. This paper proposes a static analysis smart contract read-after-write risk detection method based on key methods and call chains. The scheme extracts key method patterns on the abstract syntax tree, identifies and locates key methods with risks, greatly reduces the interference of useless nodes on detection, and realizes rapid detection. By constructing the key method call chain, the real call scene is restored according to the call type and attribute of the key method. After experimental verification, compared with the current popular smart contract risk detection tool Revive^CC, the tool proposed in this paper has higher detection accuracy and can more accurately locate the read-after-write risk in smart contracts.

Trusted decentralized applications based on distributed ledger technologies provide many potential opportunities to 5G applications and verticals, as well as in fifth generation mobile network (5G) enabling technologies, systems, and services. Apart from the tamper-proof exchange of transactions, distributed ledgers can provide a software environment for the trusted execution of smart contracts. In this article, we explore the security aspects of decentralized applications and, in particular, the security of smart contracts. Distributed ledger characteristics impose distinct requirements on smart contract design, implementation, deployment, and management. We briefly present the approach to the development of secure smart contracts, and highlight key smart contract vulnerabilities and the developer tools supporting smart contract security. We developed a secure, upgradeable modular multi-contract platform. It combines per-contract Smart Contract Tunnels and per-user-based access control to minimize vulnerabilities. The smart contract platform is comprised of service-agnostic, auxiliary, and service-specific smart contracts. It can be therefore easily adapted to different 5G application verticals. For illustration and evaluation, we elaborated on the proposed solution on a case of smart electric charging. During the design and development, state-of-the-art code analysis was applied. Finally, we propose an architecture for the integration of the secure multi-contract platform into a 5G architecture. The integration proposal utilizes hybrid private-public blockchain networks for possible security, scalability, performance, and transaction cost optimization.

Blockchain-based smart contracts are self-running computer programs that can automate a variety of commercial activities. Currently, the majority of these decentralized applications are developed using smart contract platforms like Polkadot, Cardano, and Ethereum. In addition to analyzing current technology developments and prospective future applications, this article provides a historical review of smart contract platforms. The study emphasizes the significance of smart contract platforms for supporting blockchain-based applications and enabling decentralized finance (DeFi). It also looks at the emergence of layer-2 scaling solutions, the introduction of non-fungible tokens (NFTs), and the growing need of interoperability among different smart contract platforms. The article also looks at the potential for multi-chain smart contracts, the effects of quantum computing, the integration of AI and ML technologies with smart contract platforms, and the potential for smart contract platforms to support decentralized autonomous organizations (DAOs). The difficulties of expanding smart contract platforms, the requirement for uniformity in the creation of smart contracts, and the potential for smart contract platforms to revolutionize sectors like healthcare, real estate, and supply chain management are also covered. The paper emphasizes the significance of ongoing innovation and development in smart contract platforms for the expansion of the blockchain ecosystem as it draws to a close.

The post-deployment challenges in developing and upgrading blockchain smart contracts necessitate a high level of accuracy in their development and business logic. However, current methodologies for verifying the business logic of smart contracts frequently fail to address their alignment with end-user business requirements. This paper introduces a two-step language transformation process to bridge this gap. Initially, we establish a transformation rule from the Business Process Model and Notation (BPMN) to Prolog, enabling the translation of business processes into a Prolog representation. This step not only validates the business process logic but also ensures it meets user specifications. Subsequently, we introduce a transformation rule from the BPMN to Go, which facilitates the transformation of the BPMN model, once validated, into a Go language smart contract. To enhance usability, we have engineered a dedicated tool that streamlines this transformation process. We present a case study involving a banking loan process to exemplify the utility of our tool in creating BPMN diagrams, conducting requirement and syntax validations, and effecting the transformation to Go smart contracts. The case study and empirical results suggest that our methodology and the accompanying tool mitigate the complexities inherent in smart contract development. They also ensure the fidelity of business logic to user demands, thereby promoting the broader adoption of blockchain smart contract technology.

Smart contracts are agreements between parties which, not only describe the ideal behaviour expected from those parties, but also automates such ideal performance. Blockchain, and similar distributed ledger technologies have enabled the realisation of smart contracts without the need of trusted parties—typically using computer programs which have access to digital assets to describe smart contracts, storing and executing them in a transparent and immutable manner on a blockchain. Many approaches have adopted fully fledged programming languages to describe smart contract, thus inheriting from software the challenge of correctness and verification—just as in software systems, in smart contracts mistakes happen easily, leading to unintended and undesirable behaviour. Such wrong behaviour may show accidentally, but as the contract code is public, malicious users can seek for vulnerabilities to exploit, causing severe damage. This is witnessed by the increasing number of real world incidents, many leading to huge financial losses. As in critical software, the formal verification of smart contracts is thus paramount. In this paper we argue for the use of deductive software verification as a way to increase confidence in the correctness of smart contracts. We describe challenges and opportunities, and a concrete research program, for deductive source code level verification, focussing on the most widely used smart contract platform and language, Ethereum and Solidity.

Many popular blockchain platforms support smart contracts for building decentralized applications. However, the vulnerabilities within smart contracts have demonstrated to lead to serious financial loss to their end users. In particular, the smart contracts on EOSIO smart contract platform have resulted in the loss of around 380K EOS tokens, which was around 1.9 million worth of USD at the time of attack. The EOSIO smart contract platform is based on the Wasm VM, which is also the underlying system supporting other smart contract platforms as well as Web application. In this work, we present WANA, an extensible smart contract vulnerability detection tool based on the symbolic execution for Wasm bytecode. WANA proposes a set of algorithms to detect the vulnerabilities in EOSIO smart contracts based on Wasm bytecode analysis. Our experimental analysis shows that WANA can effectively and efficiently detect vulnerabilities in EOSIO smart contracts. Furthermore, our case study also demonstrates that WANA can be extended to effectively detect vulnerabilities in Ethereum smart contracts.

Blockchain, or distributed ledger, provides a way to build various decentralized systems without relying on any single trusted party. This is especially attractive for smart contracts, that different parties do not need to trust each other to have a contract, and the distributed ledger can guarantee correct execution of the contract. Most existing distributed ledger based smart contract systems process smart contracts in a serial manner, i.e., all users have to run a contract before its result can be accepted by the system. Although this approach is easy to implement and manage, it is not scalable and greatly limits the system's capability of handling a large number of smart contracts. In order to address this problem, we propose a scalable smart contract execution scheme that can run multiple smart contract in parallel to improve throughput of the system. Our scheme relies on two key techniques: a fair contract partition algorithm leveraging integer linear programming to partition a set of smart contracts into multiple subsets, and a random assignment protocol assigning subsets randomly to a subgroup of users. We prove that, our scheme is secure as long as more than $50\%$ of the computational power is possessed by honest nodes. We then conduct experiments with data from existing smart contract system to evaluate the efficiency of our scheme. The results demonstrate that our approach is scalable and much more efficient than the existing smart contract platform.

Smart contracts are set of instructions which are stored on a blockchain. These instructions will be executed automatically without middle-man interaction. Smart contracts in the blockchain allows the transactions and contracts to be executed across undesignated nodes without an interaction of central system or external enforcement. The transactions are transparent, traceable and irreversible. In blockchain all the data stored are secure and immutable. So blockchain would be the suitable environment for smart contracts. Smart contract data is encrypted and placed in a distributed ledger, which means the information stored in the blocks cannot be deleted or modified. There are many blockchain platforms supporting smart contracts. This paper explores the information about various smart contract platforms and its features.

Blockchain technology has rapidly emerged with a multitude of applications, among which smart contracts have garnered considerable attention. Smart contracts represent a promising solution for streamlining trade and business transactions between untrusted parties without intermediaries. These self-executing pieces of code automatically execute predefined actions when specific conditions are met. Despite the growing enthusiasm for blockchain and smart contracts, researchers believe this powerful combination has not yet reached its full potential. Hence, a systematic study is conducted to explore the various facets of blockchain-based smart contracts comprehensively. The research follows the PRISMA framework and employs two primary approaches: bibliometric analysis and systematic literature review. The process was initiated by formulating targeted search queries within the Scopus database, identifying a total of 1,949 publications spanning from January 2019 to August 2023. Subsequently, a bibliometric analysis was conducted on these publications using VOSviewer and Biblioshiny. Further, the full text of these publications was meticulously screened to isolate those with a significant focus on smart contracts. This led to the identification of 48 publications, each offering unique insights into various smart contract applications. Upon further examination, it was observed that the majority of these publications held rankings within the China Computer Federation, which refers to the qualitative research work in this domain. The study concludes with the current state of blockchain-based smart contracts, their platforms, applications, and challenges and reveals the substantial potential in handling tasks with predefined conditions and security requirements.