Data Feeds Architecture

Chainlink Data Feeds, Offchain Reporting (OCR), and the Chainlink Runtime Environment (CRE) are the current ways to bring data and computation to a smart contract.

Data Feeds

A Chainlink Data Feed aggregates answers from many independent oracle nodes. Your contract reads that one aggregated answer. The Decentralized Data Model describes how the feed is updated and how a consumer contract reads it.

Start with Data Feeds.

Offchain Reporting

Offchain Reporting (OCR) is how those nodes agree. Each node reports its observation and signs it. The nodes then submit one aggregate transaction. The report is checked onchain against the quorum signatures. Read Offchain Reporting for the protocol.

Chainlink Runtime Environment

CRE is the orchestration layer for new multi-step work. You write a workflow with the CRE SDK in Go or TypeScript. A workflow DON runs it. The workflow can call other DONs to fetch offchain data or to write onchain. Start with the CRE getting started guide.

Basic request model

The Basic Request Model is the old path: one contract, one oracle, and one request. That page stays at the same URL so existing contracts can still be read. It is not in the product navigation. Do not use it for a new project.