How Does a ‘51% Attack’ Relate to Network Security?

A 51% attack occurs when a single entity or group gains control of more than half of the network's mining hash rate (PoW) or staked coins (PoS). This control allows them to potentially block new transactions, reverse confirmed transactions (double-spending), and prevent other miners/validators from completing blocks.

It fundamentally compromises the integrity of the blockchain.

What Is a 51% Attack and How Does It Compromise a Blockchain?
What Is Double-Spending and Why Is a 51% Attack Necessary to Execute It?
What Is the “51% Attack” and How Does It Relate to a Pool’s Size?
What Is a 51% Attack and How Does It Specifically Enable Double-Spending?
What Is ‘Double-Spending’ and Why Is It the Main Concern of a 51% Attack?
Explain the Concept of a “51% Attack” in the Context of Network Hash Rate
Why Is Double-Spending Easier on a Blockchain with Low Hash Rate?
How Does Double-Spending Fundamentally Undermine a Cryptocurrency’s Value Proposition?

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