Oracles are an important component of the smart contract ecosystem. The limitation with smart contracts is that they cannot access external data, which might be required to control the execution of the business logic; for example, the stock price of a security product that is required by the contract to release the dividend payments. Oracles can be used to provide external data to smart contracts. An Oracle is an interface that delivers data from an external source to smart contracts.

Depending on the industry and requirements, Oracles can deliver different types of data ranging from weather reports, real-world news, and corporate actions to data coming from Internet of Things (IoT) devices. Oracles are trusted entities that use a ...

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