📂 Concepts and Definitions

# Airnode

Table of Contents

Airnode is a serverless oracle node implemented with a "set and forget" philosophy.

Airnode is capable of serving one or more APIs to it's requesters which are smart contracts on chain who request the data server by the particular Airnode. Each Airnode has a unique mnemonic identifying its wallet. This mnemonic is kept in secret and Airnode is publicly identified using the default address derived from the mnemonic.

# airnodeAddress

An Airnode is identified by the default address of a BIP 44 wallet (with the path m/44'/60'/0'/0/0). This address is same for all chains on which Airnode operates. You specify the wallet mnemonic in the secrets.env file which you use when deploying the Airnode.

You can also use ethers.js to derive the airnodeAddress from the mnemonic for informational purposes.

// Get the default address of the airnode-wallet using its mnemonic.
airnodeHdNode = ethers.utils.HDNode.fromMnemonic(mnemonic);
airnodeAddress = airnodeHdNode.address;

# xpub

The Airnode owner announces their extended public key (xpub of the hardened derivation path m/44'/60'/0') off-chain for sponsors to be able to derive their sponsor wallets. This wallet will then be used by the Airnode to fulfill each request made by the requester contracts. The xpub that the owner has announced is not verified on-chain.

However, the sponsor can verify it off-chain. You can use the verify-xpub command from the admin CLI.

Last Updated: 3/7/2022, 8:32:47 AM