## 4 Descriptors of the Second Criteria and Experimental Results
### Platform Performance in Terms of Speed and Volume of Transactions  
This section discusses performance in terms of transaction execution speed, the amount of information stored in the consortium blockchain and network latency. The UniverCert platform is built on the principle of the Ethereum blockchain consortium. Compared with the public Ethereum blockchain, the role of the transaction is important here mainly for execution of the contract, not for the transfer of ETH cryptocurrency. Therefore, this article focuses on the performance and storage of executing Ethereum contracts. In the Ethereum blockchain consortium, where authorized nodes are participants and smart contracts that can be assessed by the complexity of business logic are used, it is possible to calculate the necessary performance and storage volume to make technical decisions on network maintenance and node status. This is important because, with an increase in the volume of transactions, the performance of Ethereum decreases significantly, and a great deal of space is required for data storage. The authors of a measurement study proposed a method for predicting storage performance and growth by analyzing the relationship between transaction volume and the \"state of the world\" [34]. The \"state of the world\" is implemented using the \"modified Merkle Patricia tree (trie)\" (hereinafter MPT) [35]. The speed of transaction execution in Ethereum [36] is determined mainly by the operating time of the Ethereum Virtual Machine (EVM) and the modification of the \"state of the world.\" In addition, the data volume increment depends on the scale of the transaction and the magnitude of the increment in the MPT tree. Consequently, an estimate of performance and memory size can be obtained, provided that the relationship between the volume of transactions and the \"state of the world\" is clarified. Taking into account the relative stability of EVM operation time and the predictability of contracts, we propose a formula for predicting transaction execution time and storage occupancy through the cost of maintaining the \"state of the world.\" The MPT tree, or the \"state of the world\" of Ethereum, consists of two parts: the upper tree of the State Trie contracts and the lower Storage Trie, the root of which points to the contract. Therefore, the average time to modify the MPT is determined as follows:  
\[T_{mpt}(n)=\frac{t}{2}\log(an) \tag{1}\]  
where \(a\) is the number of contract deployments in the network, \(n\) is the transaction volume, \(t\) is the execution time for creating a node in the MTP tree (sha3() calculation and database access). Given the specifics of the LevelDB database used by Ethereum [37], the time \(t\) (access to the database) increases as the amount of data storage increases. However, the calculations use the average static value of \(t\). The next step is to calculate the average transaction execution time, as follows:  
\[T_{avg}(n)=T_{exec}+T_{mpt}(n) \tag{2}\]  
where \(T_{exec}\) is the time to execute the contract on the virtual machine. From the experimental results, we find that the average time of a database visit is t = 0.03 ms under the following conditions: one Ethereum node is used without a network, only one transaction is packed into a block and 1,000,000 transactions are randomly generated. The value of the Texec parameter for the blockchain consortium is relatively stable, and its impact on the total time can be neglected.