Proof of Stake was implemented and Proof of Auction or Discretionary Mining was implemented by modifying PoS.
Key Features:
- A client node can send request to ICO for partial mining.
- ICO will broadcast it to available miners with fee limit and computation requirement.
- Miners will bid back their preferred fee.
- ICO will choose selected miners based on lowest fee and fastest time.
- Miners will do PoW of IOTA and the fastest one will add the block and get the fee.