LINK is an ERC20 standardized token based on the Ethereum blockchain, used to pay Chainlink node operators for retrieving off-chain data, formatting it into a blockchain-readable format, off-chain computations, and ensuring uptime. As part of running a node, Chainlink tokens prevent malicious actors.

1. Project Introduction

The first decentralized oracle network that allows anyone to securely provide smart contracts with access to critical external data, off-chain payments, and any other API functions. Any user who has a data feed, off-chain service (such as local payments), or any other API can directly provide it to smart contracts in exchange for LINK tokens. The Chainlink network is a distributed network of Chainlink nodes that directly feed specific data, APIs, and various off-chain payment functionalities to smart contracts. Chainlinks network is comprised of two separate parts, on-chain and off-chain components, which must interact to provide services. It is built in such a way that it can be upgraded, so different components can be replaced when better technologies emerge. The on-chain component filters oracles via service-level agreements (SLAs) based on the metrics requested by one side of a smart contract. Using these metrics, Chainlink collects responses to SLA queries, sorts them using reputation and aggregation models, and provides the final set of Chainlink query results that can be implemented into smart contracts. The off-chain component consists of oracle nodes connected to the Ethereum network that independently collect responses to off-chain requests. These off-chain nodes can be located within any industry, such as a New York Stock Exchange-operated off-chain node providing real-time accurate trade information to the Chainlink network, or a Visa network off-chain node settling transactions through the Chainlink network with consumers and suppliers. Chainlink technology aims to integrate nodes from all these industries into a common network that acts as a (low-cost) intermediary, interpreting and correctly distributing data as needed. The Chainlink system ensures that the results obtained from oracles are accurate and allows oracles to remain independent of the data they provide. Anyone who provides data, payments, electronic signatures, or other API providers, along with individual developers, can easily join the Chainlink network by connecting their familiar APIs to the network. Once an API is connected to Chainlink, the user becomes a Chainlink node operator responsible for connecting that API to the Chainlink network. To incentivize operators to provide API information, they are compensated in LINK tokens for successfully completing online link requests. Currently, the project offers a fully distributed oracle network compatible with Bitcoin, Ethereum, and Hyperledger. Other blockchains are expected to be supported in the future, allowing cross-chain connections between smart contracts and any other public or private chains, enabling anyone in the world to use the Chainlink network regardless of their platform. All service providers will be able to securely provide smart contracts with access to critical external data and potentially even off-chain payments.

2. Commentary

Chainlink (LINK) is a decentralized network that provides information (oracles) to smart contracts. Chainlink was founded in 2017 by Sergey Nazarov and Steve Ellis to solve the problem of off-chain information procurement for the execution parameters of smart contracts. Smart contracts are designed to automatically execute when certain parameters are met; however, when these parameters exist off-chain, they rely on an information source (known as an oracle) to provide the necessary information. Off-chain oracles are often centralized and depend on third parties to provide critical information in a trustworthy and timely manner. ChainLink aims to break this dependency by providing information to smart contracts through a decentralized oracle network, where oracles work together on the Link blockchain to validate and forward key information to these contracts. The ChainLink network allows users with data feeds or information-bearing APIs to easily provide information to smart contracts in exchange for LINK tokens. Milestones
September 2017 - ChainLink ICO.
November 2018 - Acquisition of Town Crier (smart contract and data privacy project).
June 13, 2019 - Announced partnership with Google. Utility
The Link network provides timely and accurate information to smart contracts through a decentralized network of oracles (data sources and APIs). This information is crucial for the effective and accurate execution of smart contracts, as the required information exists off-chain and there needs to be a reliable method to obtain it on-chain. LINK tokens are used as payment for smart contracts that utilize the data provided by the Link Network, with oracles that provide accurate information being rewarded proportionally to the LINK they stake. Key Features
Partnerships with major industry players such as SWIFT and Google.
Integration with Ethereum sidechains like Harmony, Celer, and Matic.
Average block time n/a; total supply 1 billion LINK; Oracle consensus written to the Ethereum blockchain via threshold signatures. Related Links:
https://chain.link/
https://en.bitcoinwiki.org/wiki/ChainLink
https://everipedia.org/wiki/lang_en/chainlink-cryptocurrency
https://blog.chain.link/threshold-signatures-in-chainlink/
https://blockonomi.com/chainlink-guide/