If you have read Graft white paper, you should remember that in Graft Network only full supernode is allowed to perform real time authorizations (instant approvals) which are issued by an authorization sample – a group of full supernodes that are selected by special algorithm. The main eligibility criteria for becoming a full supernode are combined PoW (Proof of Work) and PoS (Proof of Stake): the full supernode must have both a recently mined block and a stake wallet with a minimum balance of 500 GRF.
With that said, only full supernodes – authorization sample members receive transaction fees, while mining nodes receive block rewards only. But every mined block opens the door for the mining node to become a full supernode and earn even more on real time authorization and service broker hosting.
At the very beginning, right after the mainnet launch, the mining can be done using regular CPU. However, once miners start connecting their GPU cards and rigs, the hashrate will go up. We realize that at some point, sooner or letter, the miners will start consolidating into mining pools due to the raising hashrate. Such consolidation will reduce the overall number of “unique” mining supernodes, which may affect the number of supernode candidates that are eligible to become a full supernode.
In order to maintain the combined PoW/PoS scheme relevant while keeping up with constantly rising hashrate, we introduce superstake – a mechanism which allows a single mining supernode associated with mining pool to be linked to more than one stake wallet. Thus, a single mining wallet can be linked to multiple stake wallets, which allows a single miner to maintain multiple full supernodes, which will increase an income from transaction fees. However, only up to 3 full supernodes linked to the same mining wallet can participate in the same authorization sample. Also, the stake for extra full supernodes added to the same miner is doubled in order to compensate for the fact that a single miner controls a larger piece of the network (and receives extra portions of transaction fees).
The superstake approach does not change the existing requirement to have at least 500 GRF stake plus recently mined block in order to become a full supernode. However, the second full supernode connected to the same miner will increase the required stake amount to 1000 GRF each. The three supernodes will require a 2,000 GRF stake per each “sister” supernode, etc. Although there is no limit for a number of superstake supernodes, only up to three “sister” supernodes can participate in a single authorization sample. The superstake supernodes can be also used for hosting service brokers that cannot be hosted together with real time authorization for any reason (for example, elevated security or privacy requirements).