Ethereum: Understanding Transaction Numbers in Each Block

As a decentralized and open-source blockchain, the Ethereum network operates with a unique architecture that allows it to process transactions at incredible speeds. One of the key components that enables this efficiency is the block structure, which is made up of a collection of transactions. In this article, we’ll delve into how many transactions are included in a single block, who can decide how many transactions will be performed in a block, and what happens if multiple transactions are selected.

Block Structure and Transaction Count

An Ethereum block is essentially a temporary storage container that contains a collection of transactions. Each transaction consists of the sender’s account balance, the recipient’s address, and the amount to be transferred (in Ether or other cryptocurrencies). Typically, the block structure consists of:

• Header: Contains metadata about the block, such as its number, timestamp, nonce, and hash.

• Body: The main part of the block, which contains one or more transactions.

• Footer: Includes the Proof-of-Work (PoW) solution required to create a block.

In terms of the number of transactions, each block can contain anywhere from a few dozen to a few thousand transactions. This is because Ethereum uses a consensus mechanism called Proof-of-Stake (PoS), which incentivizes interested users to participate in the network by investing their ether as collateral.

Who decides the number of transactions in a block?

The decision on the number of transactions in a block is the responsibility of the Ethereum network protocol, specifically Beacon Chain and its future updates. Beacon Chain is an ongoing process that aims to increase the speed and scalability of the network by introducing new features such as Proof-of-Action (PoA), which validates validators with transaction fees based on their activity.

Beacon Chain’s PoA mechanism ensures that a large number of transactions are completed in each block, while also providing a more efficient and scalable system. The current consensus protocol, called Casper, introduces a new approach to selecting transactions in each block, known as proof of concept (PoC).

How ​​transactions are selected in a block

In the context of PoC, validators compete to create the smallest block by solving a mathematical puzzle that requires computing power and memory. This process is known as a “proof of capacity,” or PoC. The selected transactions are then included in the block.

When a validator submits a block for verification, they must prove that their proposed block meets the required criteria, including:

• Block size: The total block size must be less than a certain threshold.

• Hash: The hash of the block must be unique and not previously used.

• Number of transactions: The number of transactions in the block must meet certain criteria.

If a validator successfully submits a block that meets these requirements, their transactions will be selected for inclusion in the next block.

Priority and Fee Selection

Regarding fee selection, validators who submit blocks with a more complex transaction structure or higher priority (i.e., those that require more computing power to verify) are given a larger share of the transaction fees. This incentivizes validators to create high-quality blocks that not only meet but exceed the block validation criteria.

In summary:

• The Ethereum block structure allows for tens to thousands of transactions per block.

• Beacon Chain and subsequent upgrades such as Casper introduce mechanisms such as Proof of Action (PoA) and Proof of Capacity (PoC) to increase the number of transactions while maintaining efficiency.

• Transaction selection is based on criteria such as block size, hashrate, and number of transactions.