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30:. Oracles provide trusted information based on the outside-world sources to the on-blockchain smart contracts. An oracle typically encapsulates the real-world complexity outside of the blockchain. This provides different engineering advantages, chiefly that critical errors and potential points of failure are easier to mitigate off-chain than on-chain.
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For example, in a contract to automatically purchase bitcoins at a predetermined price, the fulfillment condition is based on the current exchange rate for the bitcoin; an off-chain oracle can constantly monitor the price to provide the triggering condition to the contract.
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oracle handles the results of the smart contract (for example, paying a fee) by manipulating a real-world device (say, opening he door). It code can also be stored on-chain;
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oracle executes the code that is actually stored on-chain and provides the result (say, the bitcoin price matching the condition) as an input to the contract;
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is an aggregator of many oracles to determine the condition when the real-world oracles disagree.
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oracle that is built-in into a physical sensor (for example, the same traffic camera);
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181:"Mutual Recognition Mechanism Based on DVCS Oracle in the Blockchain Platform"
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Utilizing
Blockchain Technologies in Manufacturing and Logistics Management
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Kustov, Vladimir
Nikolaevich; Selanteva, Ekaterina Sergeevna (2022).
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Kustov and
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An off-blockchain source of input data for smart contracts
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