The proof-of-work system/protocol, was first used in the mid-1990’s for fighting spam emails. The idea never found a truly useful cause until 2009 when bitcoin was created. Bitcoin itself utilizes this protocol in its transaction blockchain and thanks to this we can witness the growth in bitcoin mining. The base idea of this lies in a challenge and proof (or response). The challenge is a transaction, which is a specific cryptographic puzzle. The proof is that a miners computer cracks the puzzle, so the transaction goes through. And that is proof of the miners’ work and him providing his hardware for the validation of transactions. The more hash power a miner can provide for validating transactions, the bigger his cryptocurrency coin reward for the service is. The problem with PoW is that mining has become so large that miners are investing into giant A.S.I.C. hardware which is highly energy consuming. Many mining farms are built around the globe as bitcoin has risen in value.
The proof-of-stake system works on a principle of validators of a block being chosen randomly. The validators can higher their chances by having the largest stake in each validation. The higher the money deposit in the block (or stake), the higher the chance of validating the block and later on receiving the transaction fees.
This particular system is more considerate to the environment as it doesn’t require large amounts of energy and hardware.
The proof-of-capacity protocol is the newest, being introduced in 2013. In this protocol, coins are distributed among miners over a long period of time. All that is needed is hard drive space in order to mine.
Proof – OF – Stake – TIME (PoST)
Proof of Stake-Time is a consensus algorithm which works on the basics of Proof of Stake but adds a stake-time feature which increases the odds of staking over time. This leads to more active staking and also strengthens the decentralization of the algorithm.
Delegated Proof of Stake (DPoS)
The idea of Delegated Proof of Stake is that the cryptocurrencies holders vote on a selection of 101 delegates who create new blocks in the blockchain and collect block rewards. Each round of consensus consists of 101 blocks with each delegate assigned one block forge. If a delegate is unable to forge their assigned block, the activity in that block is moved to the next block.
Because of the low number of block producers, DPoS protocol has slipped into losing its decentralization for throughput which is in a way losing the basic idea of cryptocurrencies.
Proof of Authority (PoA)
The Proof of Authority consensus algorithm uses the factor of one’s identity as a stake in the validating of blocks. This way it can determine easily if the block validator is sufficient enough for the task.
Trustless Proof of Stake (TPoS)
Trustless Proof of Stake introduces staking as a business where a merchant can stake coins of others in a goal of a block verification reward. This will allow your coins in cold storage to be actively staked.
Proof of Signature PoSign (PoSP)
Proof of Signature PoSign contains a feature of STATIC nodes which verify new blocks. In order to sign off a block, it has to validate a transaction. Any malicious nodes are automatically blacklisted.
Distributed Proof-of-Research (DPoR)
Proof of Reputation works on the basis of validating nodes being required to have a certain reputation in order to have power over validating new blocks and transactions. That means the participating block signer would face financial consequences in the case of him cheating the system. This ensures better security and is far more green than PoW and etc.
The Proof of Research algorithm uses the Proof of Stake algorithm in the process of “mining” for which miners need a wallet with the cryptocurrencies coins on it which act as a stake.
Gridcoin is both a PoS and PoR coin and by combining these two, PoS gives the coins its desired security and also its energy-saving features.
The Quantum Proof of Stake or QPoS consensus algorithm holds the same base core like a normal PoS algorithm, in which validators stake their share in the block creation which is carried out by the largest staker. The QPoS is also resistant to both classic and quantum computing attacks. Hopefully this combination will create an even safer and more energy saving algorithm which will be available to more cryptocurrencies than only QRL.
Proof of Devotion (PoD)
The Proof of Devotion algorithm is a combination of Delegated Proof of Stake and Proof of Identity. This can help to create an even more secure consensus algorithm.
Proof – OF – Cooperation (PoC)
Proof of Cooperation instead of competing works on the basis of cooperation. Each node works with each other to validate transactions and form new blocks for the blockchain. Creating blocks is effortless, that’s why the algorithm saves power and can be run on even smallest of devices.
Delayed Proof-of-Work (dPoW)
The Delayed Proof of Work consensus method was first used on Komodo, a cryptocurrency connected to Bitcoins blockchain and utilizing its hash rate. A dPoW blockchain can be attached to any PoW blockchain and can either use the Proof of Work or Proof of Stake consensus.
dPoW has two different types of nodes. Normal nodes and 64 notary nodes, which are voted in by the dPoW blockchains stakeholders. These notary nodes need a majority of 33 to sign a completed block into the Bitcoin blockchain.
When mining, notary nodes are allowed to mine at a lower difficulty of mining than normal nodes which adds on security and prevents mining wars.
dPoW reduces high energy usage by preventing mining with ASICs and uses a circulating right to mine method for notary nodes which decreases the competition between nodes, hence saving energy.
The Quantum Proof of Stake or QPoS consensus algorithm holds the same base core like a normal PoS algorithm, in which validators compete in who validates each block and the higher the money deposit in the block (or stake), the higher the chance of validating the block on the ledger and later on receiving the transaction fees, but will also be resistant to both classic and quantum computing attacks. Hopefully this combination will create a even safer and energy saving algorithm which will be available for more cryptocurrencies than only QRL.
Proof of Existence (PoE)
Proof of Existence is a service which wishes to help notaries with the process of authenticating timestamped documents via the bitcoin blockchain. It was first developed as an open source project in 2013.
Proof of Process (PoP)
The Proof of Process protocol uses the trust of all parties in a process, which can be a flow of information or an action. This will eventually help data handling in many directions.
Proof of Importance (PoI)
Proof of Importance was first developed for the NEM blockchain platform. Similarly like the PoS network, the nodes compete on who will verify the next block. This is determined with the “importance” of each node. The importance score contains factors like amount of the blockchains coins held, amount of transactions in the last month, and more. This provides a positive difference opposed from PoS where the argument could be it benefits mainly crypto hoarders.