Double-spending prevention is the fundamental security challenge addressed by blockchain technology, ensuring that a single unit of digital currency cannot be spent more than once. In traditional finance, central authorities prevent this by verifying transactions against a central ledger. Decentralized systems require a different approach to maintain trust.
Consensus
Consensus mechanisms achieve prevention in a decentralized environment by ensuring all network nodes agree on the order of transactions and the state of the ledger. Proof-of-Work and Proof-of-Stake protocols make it computationally prohibitive for an attacker to reverse a confirmed transaction. The network’s collective agreement makes it nearly impossible to alter past transaction history.
Integrity
The integrity of the network is maintained by requiring a significant amount of computational work or staked capital to alter past transaction history. Once a transaction is included in a block and added to the blockchain, it is considered final and irreversible. This integrity allows for the secure settlement of financial derivatives and other complex smart contract operations.
