Despite the fact that smart contracts are a relatively new feature that started to be actively integrated into blockchain ecosystems not so long ago, we can confidently say that smart contracts have become one of the main catalysts for the development of modern blockchain technologies. There are several reasons for this:
- SC is impossible to hack. A fraudster making changes to the smart contract code on their node will not lead to its correction since this copy will be rejected as incorrect on other nodes;
- The terms of the transaction after placing the contract on blockchain can be changed only if it is provided for by the code, and the consent of all interested parties is required.;
- the execution of smart contracts, ensuring complete security, does not require the participation of a third party;
- both common and proprietary programming languages can be used to create SC, which, on the one hand, simplifies the writing of scripts and on the other hand, expands the functionality of smart contracts.
It is not surprising that a significant part of active blockchain platforms either use or are planning to implement the use of smart contracts on their decentralized networks. Let’s look at the most famous platforms and consider their advantages, features, and disadvantages.
Ethereum
This blockchain is one of the pioneers of the use of smart contracts, and it is this circumstance, despite the imperfection of the methods used, that has provided active support from other developers.
Advantages:
Turing completeness
extensive developer-level support, one of the best smart contract support platforms by a combination of factors.
Disadvantages: limited capabilities of the programming language used. Compared to such popular programming languages as C++, Python, or C#, Solidity is not that well structured. As a result, if the written code is not efficient enough, the cost of implementing a smart contract on the Ethereum platform will be too high.
An EVM virtual machine is used to execute the smart contract code, while the terms of transactions are checked by each miner. The advantage of the Solidity language can be called Turing completeness compliance, but it had to pay for it with insufficient flexibility of the functionality. In particular, there are difficulties with the implementation of multidimensional arrays (they cannot be passed directly as parameters).
Smart contracts on this platform are limited in the number of supported parameters (maximum sixteen), which does not allow the implementation of sufficiently complex projects.
Quorum
A platform based on the Ethereum SC but offering transactions without charging fees.
Advantages: Turing completeness, a special function that provides support for transactions between many participants of the transaction, which makes the platform perfect for being used on corporate Apps.
Disadvantages: it is not very popular among developers, and this platform is characterized by all the disadvantages that the Ethereum network has.
The contract blockchain uses two databases: an open one for recording public transactions and a closed one, in which information on private transactions is recorded.
Wanchain
In essence, this platform is a branch of Ethereum, so the influence of the parent network is clearly obvious here.
Advantages: the developers supplemented the features with the ability to ensure the confidentiality of participants in transactions, and this allowed the implementation of smart contracts in cross-chain transactions.
The disadvantages are the same as those of the Ethereum platform.
Anonymity in Wanchain is ensured by using a one-time address and ring signature technology. Note the full compatibility of Wanchain smart contracts with Ethereum DApp.
Zen
A feature of this platform is the implementation of its own programming language for smart contracts.
Advantages: the proprietary F# language minimizes the error probability on the code due to the use of dependent typing. Having Turing completeness, F# provides the possibility of formalized verification of data types – constants, variables, and expressions.
If errors were made when writing code with typing, the compiler would crash. The contract code is placed separately on the local node, which allows for an increase in the speed of contract execution due to the parallelization of calculations, and this is better than an interpreted model. There is no support for a virtual machine, no traditional states – only functions embedded in the algorithm, which also has a positive effect on the speed of transaction processing.
Rootstock
A feature of the platform is the use of open source SC, while it still supports two-way communication with the Bitcoin network.
Advantages: Turing completeness, support for smart contracts based on BTC.
Using TCVM integrated into the Bitcoin network allows you to improve the scalability and speed of transaction processing, which is still the Achilles’ heel of the first cryptocurrency. It was Turing Complete VM that made it possible to expand the functionality of smart contracts when using the Solidity programming language.
The availability of rewards for miners is designed to actively involve them in the use of smart contracts, which should increase the attractiveness of the Bitcoin ecosystem.
Qtum
Another platform is based on Ethereum and designed to improve it by integrating an optimized blockchain algorithm and a new consensus algorithm.
Advantages: increased network scalability, simplified payment verification, reduced use of the formal transaction verification tools.
Disadvantages: the use of an EVM virtual machine and the Solidity language with all the disadvantages typical for the Ethereum platform.
It is believed that Qtum is the best choice in such niches as the Internet of Things and lightweight mobile Apps, and the intention to introduce an x86 BM will significantly expand the scope of the platform, although without improving the security parameters of the blockchain.
NXT
A platform that allows users to design smart contracts independently.
Advantages: templates that simplify the creation of SC.
Cons: lack of Turing completeness.
However, this disadvantage is compensated by the fact that ready-made NXT smart contract templates provide support for a complete Turing scenario, simplifying their creation and allowing support for most commercial Apps.
Cardano
The emphasis of this platform is to ensure maximum security when executing smart contracts.
Advantages: the use of a bunch of languages Solidity+Plutus, allowing to eliminate loopholes in the code of smart contracts.
The Cardano blockchain uses its own CC – CCL platform, which consists of two components: a formalized virtual machine based on the language structure described above and an official formalized language that simplifies the verification of the smart contract code.
Of course, the list of platforms supporting smart contracts is much wider. They also include the Decimal community, which allows you to use smart contracts to create your own tokens or NFT. We should also mention such well-known blockchains as æternity, Counterpart, RChain, Ark, EOS, Neo, Nem, Waves, Stratis, Stellar, HyperLedger Fabric, Corda, Neblio, Viacoin, Tezos, DFINITY, BOScoin, Agoras Tauchain, Burst, iOlite, ByteBall, Universa, Urban, Soil, Expanse, Ubiq, Ethereum Classic, Monax. Most of them are based on the Ethereum platform, but there are also original projects that use popular or proprietary programming languages and have a number of advantages and implementation features.
There is no doubt that the growing popularity of smart contracts will contribute to the further growth in the list of blockchains supporting this promising technology.