Home Tech Consensus and History in Blockchain Networks

Consensus and History in Blockchain Networks

by Maria L. Searle
consensus and history in blockchain networks

Nodes As a Mainstay of the Blockchain

Blockchain networks, like living organisms, cannot function without regulation of activity, energy flow, mainstay structure, memory, and security, and all these functions must be interconnected. Regulation of the network’s activities is ensured by established rules and consensus algorithms, and the movement of energy within it is ensured by transactions.

Regarding the mainstay structure, security, and memory, the principal performers of these functions are the nodes. The task of the nodes, which are engaged in checking, confirming, and transmitting transactions, as well as exchanging data between servers, is to ensure that their blockchain network contains only reliable information.

It follows from this that nodes are the mainstay points that ensure decentralization, stability, steadiness, and security of any blockchain network, which means that the more nodes in the network, the better.

Nodes are divided into several categories, of which the most ideal, not only for work but for analytics and auditing as well, are archive nodes. Archive nodes are the best keepers of memory and invaluable information.

They have only one drawback – they are quite voluminous, which means they are resource-intensive and expensive to maintain. However, users should not despair because instead, they, the trusted providers, can take over the service of archive nodes.

Consensus Mechanism

It is impossible to talk about the practical implementation of the requirements for decentralization and security of blockchain networks without mentioning the corresponding principles for achieving consensus. The consensus mechanism can be reviewed in the following simulated situation.

The practical implementation of blockchain technology begins with the fact that any of its participants can form transactions and send them to the network. There, blocks are created from transactions, which are spread among all participants in this blockchain network.

All this activity is regulated by a mechanism called consensus. Its job is to determine which transactions, which blocks, and which history of those blocks are correct. Since we are talking about decentralized blockchain networks, reaching consensus should also be carried out in a decentralized way.

In other words, the decision should not be made by one participant (node), but by a certain algorithmic approach, in which many nodes participate, and which is decentralized and anonymous.

Despite the fact that the approach to achieving consensus is not innovative in itself, it was this version that first appeared with the advent of the first blockchain network and has already proven its usefulness and effectiveness in practice.

To summarize all of the above, it can be stated that, in addition to other tasks, nodes in the blockchain network also perform actions to verify transactions and blocks along with their history. As a result of this check, nodes must either confirm the entry of new transactions and blocks into the block history or reject them as incorrect.

It is this final stage – accepting blocks with transactions into history or rejecting them – that completes the consensus task. After this, history cannot be reversed, and no changes can be made to it. In other words, a blockchain is a decentralized database into which information can only be added.

Verification Steps

Each network node begins to manage the correctness of actions by the initial check of transactions. This includes checking that the appropriate fields for the transaction data are filled in correctly. If there are errors or gaps in the filling, such a transaction will not be accepted.

Transactions that have passed the verification of the correctness of the data are ready for inclusion in the block, and at this stage, one more check is carried out in terms of the correctness of data activation. This check is carried out to ensure that the funds or assets included in the transaction are actually present.

Additionally, in some blockchain networks, for example, in Ethereum, the order of transactions entering the block is also checked at this stage. If the verification result is positive, the transaction is included in the block.

The block with the transactions included in it, having received the necessary cryptographic attributes in the form of a hash function, is ready to send to the network. At this stage, it must pass a new check, during which the network decides on its ability to form a transaction history, that is, the history of changes in the balance on user accounts.

In a decentralized network, there is a high probability that, at the same time, different nodes can release blocks with approximately the same transactions into the network. Obviously, some of these blocks will be perceived by the network as incorrect.

The method for identifying incorrect blocks is quite complex, but, in principle, it depends on the speed at which they enter the block history database. If the history shows the presence of an already processed block with similar transactions, then any subsequent resembling blocks will not be accepted by the network.

You may also like