Chainlink

Chainlink (LINK) is a decentralized oracle network that links smart contracts to data from beyond their own blockchain. A blockchain cannot look up outside information by itself, so the network carries checked data to the contracts that request it. The project came from Sergey Nazarov and Steve Ellis in 2017. The white paper was written together with Ari Juels.

The network relies on independent nodes that retrieve, validate and deliver data. It has a group of nodes gather figures for a request such as a stock price, then aggregate them into one agreed result. Its services are Data Feeds, CCIP, which handles messaging and token movement across chains, Automation, which sets contract actions in motion, and Proof of Reserve, which checks that assets are collateralized.

The LINK token compensates node operators for their work, tops up subscription accounts and backs network security through staking. It has node operators lock up LINK as collateral, which can be slashed when the data they deliver is inaccurate. The September 2017 ICO raised $32 million. Its tools for institutions include a runtime environment for tokenized assets, Confidential Compute and an Automated Compliance Engine.