Çifte Harcama
Dijital parayı iki kez harcama riski.
Double-spending is the central problem that all digital currency systems must solve. Since digital information is infinitely reproducible, a user could theoretically 'copy and paste' a digital coin to spend it twice. Centralized systems solve this with a master ledger (bank). Decentralized systems like Bitcoin solve it using Consensus Mechanisms (Proof of Work) and a globally shared blockchain, where transactions are timestamped and verified by a network of nodes.
graph LR
Center["Çifte Harcama"]:::main
Pre_blockchain["blockchain"]:::pre --> Center
click Pre_blockchain "/terms/blockchain"
Pre_hashing["hashing"]:::pre --> Center
click Pre_hashing "/terms/hashing"
Pre_cryptography["cryptography"]:::pre --> Center
click Pre_cryptography "/terms/cryptography"
Rel_51_percent_attack["51-percent-attack"]:::related -.-> Center
click Rel_51_percent_attack "/terms/51-percent-attack"
Rel_consensus_algorithm["consensus-algorithm"]:::related -.-> Center
click Rel_consensus_algorithm "/terms/consensus-algorithm"
Rel_block_reorgs["block-reorgs"]:::related -.-> Center
click Rel_block_reorgs "/terms/block-reorgs"
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🧒 5 yaşındaki gibi açıkla
Gerçek dünyada, birine bir dolar verirseniz, o artık sizde değildir. Ancak dijital dosyalarda, kopya oluşturmak kolaydır. Blokzinciri, birinin dijital 'dolarını' kopyalamasını ve aynı anda iki farklı kişiye vermesini engeller.
🤓 Expert Deep Dive
The 'Byzantine Generals Problem' is the theoretical root of double-spending prevention. Bitcoin's Nakamoto Consensus used PoW to create a relative time-ordering of transactions. If a user tries to spend the same UTXO (Unspent Transaction Output) in two different blocks, the network only accepts the first one validated. 51% Attacks are essentially attempts to manually induce double-spending by rewriting the blockchain's history.