## 2 Related Work
It lists several problems, such as duplication or errors related to paperwork, the possibility of fraud and failures in the existing system due to natural disasters. To avoid these problems, a blockchain-based solution is proposed that includes all the descriptors of the initial evaluation. The paper not only meets the requirements of the primary criteria but also covers one of the most important factors of the secondary criteria; more precisely, transaction costs are estimated on the Ethereum platform. The proposal uses three smart contracts and calculates the cost of each, followed by an estimate of the cost of launching the solution in Brazil, namely the amount of gas per student per year. However, this paper does not address two important aspects of the secondary criteria, namely data storage and latency. In the World State study, a model is proposed that predicts the performance and storage of executable contracts for the Ethereum Consortium Blockchain based on transaction \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & \multicolumn{2}{c}{**Theory-Based**} & & & \multicolumn{2}{c}{**Practical**} \\ \hline
**Blockchain Systems/Key Factors** & **Decentralization** & **Transparency** & **Immutability** & **Safety** & **Time** & **Data Volume** & **Transaction Cost** \\ \hline UZHBC & + & + & + & + & - & - & - \\ McRhys & + & + & + & + & - & - & - \\ ECVS & + & + & + & + & - & - & - \\ ERBC & + & + & + & + & + & + & - \\ Brazil proposal & + & + & + & + & - & - & + \\ World State & + & + & + & + & + & + & - \\ Ethna & + & + & + & + & + & - & - \\ UniverCert & + & + & + & + & + & + & + \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Solution category. volume [30]. This article focuses on the relationship between time consumption and data storage using formulas; then, an experiment is conducted to confirm the predicted data. Thus, the authors consider two estimated indicators, namely time consumption and storage. However, the cost of transactions is not taken into account. Ethna [31] provides a tool called the Ethereal network analyzer for research and analysis of the Ethereum blockchain P2P network. Although the main purpose of this paper is to describe a new method to accurately measure the degrees of Ethereum nodes, the authors also measure the transaction-propagation time, a secondary evaluation criterion. Our proposal differs from the above solutions. In particular, our previous study covers all aspects of the first evaluation criteria, whereas the present study discusses practical solutions in terms of latency, data storage and transaction costs, which are key factors of the secondary criteria. Further, our hypothesis is confirmed by the results of the experiment. In addition to the cost and quantity of transactions, we also take into account the speed of the network and execution of the transaction, thereby conducting an extended evaluation of the platform. Currently, Ethereum is the largest platform for running decentralized applications; however, it has certain limitations that cannot be solved now. First, these are low throughput and high gas fees. There are more optimized and younger second layer networks, such as Solana and Polygon. The main goals of these networks are to reduce the amount of time it takes for blockchain nodes to synchronize or reach a consensus. The Solana network uses its own Proof of History (PoH) algorithm along with the Proof of Stake (PoS) algorithm. PoH allows one to record an event that has occurred even before the information about the transaction is added to the blockchain. In this way, nodes on the Solana blockchain can create blocks without having to \"coordinate\" their actions with the entire network. This reduces the amount of transaction time. It takes 400 ms to generate one block in Solana. The maximum network throughput exceeds 50,000 TPS. However, there are only a few dozen decentralized applications (dapps) running on the network today, whereas Ethereum already has several thousand.