Is it possible to launch a DDoS attack using Ethereum’s blockchain ?

Ethereum transactions are recorded within the blockchain only on payment of fees by the sender which acts as a direct incentive for the miner to record the transaction accordingly within the Blockchain.

A DDoS attack on Ethereum Blockchain would imply that a person attempts to utilize all of the network’s resources in a way that the miners are unable to cater to or record any other transactions that are to be performed.

Given that Ethereum transactions require gas to be spent in the form of ether for every transaction and in the case of smart contracts, gas is spent at every iteration of a loop which ensures that there can be no infinite loop since all the gas in any designated account(wallet) is bound to get empty sooner or later. Whenever the wallet is indeed empty and the loop is terminated.

This ensures and protects the Ethereum Blockchain against DDoS attacks.

Ethereum has expressed plans to switch from proof of work to proof of stake at one point and whenever that does happen, the slightest chance of a DDoS occurring is eliminated as anybody that tries to perform such an attack would be required to hold a higher stake than all the ether issued.

Any person that does indeed hold a higher stake than the rest of the Ethereum Network has his percentage of shares being diluted every single minute and on him performing a DDoS attack, he’d be the person incurring the maximum amount of damage.

Unless there is a conflict of interest with the highest stakeholder it is highly improbable for a DDoS attack to occur and with his stake reducing every minute, it becomes nearly impossible for such an attack to take place in reality.

References:
Denial-of-service attack — Wikipedia
Account Types, Gas, and Transactions

Definition:
In computing, a denial-of-service attack (DoS attack) is a cyber-attack where the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a hostconnected to the Internet.

I hope this was helpful.

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