An oracle is a particular entity, such as a known API, machine or alternative blockchain, trusted by the participants in a blockchain to execute particular code.
Igor Lilic, Full Stack Software Engineer at ConsenSys, introduced PoPA:
“Today, we are debuting a main-net Oracle: Proof of Physical Address (PoPA). We are working hard to help define exactly what “Know Your Customer” (KYC) means on the blockchain and PoPA is a tangible example of an attestation Oracle that will help power our suite of blockchain KYC tools.
Each individual tool in our kit provides a base set of functionality which, admittedly, is not particularly revolutionary. The set of use cases where knowing that your counterparty has a physical location is limited (though with the advent of OpenBazaar and SafeMarket, the value add of PoPA is more tangible).”
PoPA is just the first KYC oracle planned by ConsenSys. The developer will create a “web of trust” through blockchain-based reputation by stacking sets of different KYC oracles, such as proof-of-photo-ID and proof-of-account-ownership. This stack of KYC oracles will form the crux of its blockchain identity solution, uPort.
PoPA utilizes a form that asks for a physical address. After submitting the form and paying the deposit of 0.62 ETH ($5 USD worth of Ether), ConsenSys will send the user a postcard to the address listed. This postcard will contain a unique identifier associated with the user’s address.
After receiving the postcard in the mail, the user needs to navigate to the Register page and enter the unique identifier as well as desired Ethereum address. Upon submission, the oracle will update its registry, and the provided Ethereum address will be registered on the blockchain for 365 days.
By starting to verify your identity early, you are joining a select group of pioneers — just imagine one year from now when opening a bank account just requires a single click.
We hope Proof Of Physical Address helps to convey a clear idea of blockchain-based oracles.