Blockchain-based Certificate System

Existing Use Cases for certificates:

• wedding certificates
• movie tickets

How can it be built:

• store hash of a scanned document (been there, done that)
• create a real digital certificate (that's what we do!)

Existing standards we can build on:

• ERC721
  • data model
    • name: "ReDI-School Certificates"
    • symbol: "ReDI"
    • tokenURI: hashOf({ identity: hashOf(name of certificate holder,hashOf(date of birth)) date of issuance name of course skills learned how many hours how many session start date of course end date of course });

Frontend/Interface for

• minting/creating/issuing token
  • depends on governance system for minting token
  • input
    • all the data of the tokenURI-json
  • architectural decisions
    • users use metamask to authenticate themselves
• validating token
  • input
    • name of token holder
    • either
      • hashOf(date of birth of token holder), or
      • date of birth of token holder
  • output
    • PDF
      • content of tokenURI-json-file
      • name of token holder
    • html
  • architectural decisions
    • don't send name/dob of token holder (used as input for validation) to the backend but render the certificate on the frontend in the browser/app
• listing, managing token
  • school
    • to give statistics
    • prove how many students got certificates
    • which courses etc.
  • teachers & students
    • get a list of all their certificates
    • look at individual certificates (=validation interface)
    • transfer token to a new address

Backend

• Blockchain serves as certificate database -> jsonHash
• IPFS -> json-file
• Classic Server -> HTML, Javascript, Image Files (web assets)

Workflow/Governance

1. ReDI needs to install the ERC721 smart contract
2. ReDI needs a PKI ** backup private keys ** keep private keys secure ** hot wallet, cold wallet
3. Governance around minting of token ** Possibility 1: Head of ReDI-School mints token herself ** Possiblity 2: Head of ReDI-School can delegate minting right to en employee ** Possibility 3: Head of ReDI-School can delegate minting rights to a number of people where a quorum has to approve the minting of a new toke