What Is the Role of the Blockchain’s Consensus Mechanism in Preventing Double-Spending?

The consensus mechanism, such as Proof-of-Work (PoW) in Bitcoin, ensures all network participants agree on the validity and order of transactions. Once a transaction is included in a block and that block is confirmed by subsequent blocks, it is virtually irreversible.

The longest chain rule dictates that the network accepts the history that required the most computational work, making it prohibitively expensive to reverse and double-spend.

What Role Does the ‘Delivery Mechanism’ Play in Preventing Market Abuse?
Explain the Role of a Nonce in Preventing Double-Spending
How Does the Concept of ‘Consensus Mechanism’ Relate to the Underlying Blockchain Technology?
What Role Does the “Hashing Power” Play in the Security of the PoW Component of PoA?
What Is the Primary Role of Proof-of-Work (PoW) in Securing the Bitcoin Network?
Compare and Contrast the Security Implications of Proof-of-Work (PoW) versus Proof-of-Stake (PoS)
How Does the PoW Process Prevent a “Double-Spend” Attack?
What Is the Role of a Consensus Mechanism in a Private Blockchain?

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