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Data feeds

Smart contracts crucially need off-chain data to build real-world applications, such as DeFi applications. Data feeds are the main mechanisms that meet this need. A data feed is essentially a bridge between a chain and the real-world that actively serves the latest off-chain data.

Nodary uses the Beacon framework to build data feeds, which is a modular type of data feed that was developed by API3 to make data feed deployment efficient.

How does it work?​

Beacons follow a set of update rules to update on-chain data with Airnode. Once an update rule is satisfied, on-chain data is updated as soon as possible with the latest data provided by the Nodary API.

Update rules​

Beacons are updated based on 3 conditions. Heartbeat interval, deviation threshold, and amount in the corresponding sponsor wallet. With an adjustable period, the deviation between Beacon data and the corresponding off-chain data is calculated. If the deviation exceeds a predetermined threshold, which is 1%, and the sponsor wallet has enough currency, the Beacon is updated. If there is no deviation between beacon data and off-chain data, every 86400 seconds (equals to 1 day), the Beacon is updated, of course, if the corresponding sponsor wallet is funded. See Sponsors section for each data feed in here.

Optimized update rules provide,

  • 📈 Less and meaningful updates
  • 🚦 Less data traffic on network
  • 👛 Decreased gas costs