Metaverse Pillars of Creation: PoS mining

Laurent Salou
Metaverse
Published in
6 min readJan 31, 2019

Metaverse Pillars of Creation (MPC) is the next major upgrade of Metaverse blockchain. This major upgrade is divided into 2 phases: double consensus PoW/PoS in phase 1 and triple consensus PoW/PoS/dPoS in phase 2.

Following the global crypto market, most of PoW blockchains are facing a drop of their mining difficulty, exposing them to 51% attacks or selfish mining. This risk was highlighted by the recent attack of ETC, leading to thousands of ETC lost for the impacted exchanges.

In order to face this issue, Metaverse is implementing a double consensus PoW/PoS in MPC phase 1, followed by a triple consensus PoW/PoS/dPoS in MPC phase 2. These changes will greatly improve the security of Metaverse by highly increasing the complexity and cost of such attacks.

Double and Triple consensus

After the release of MPC phase 1, the rates of each type of mining will be as below:

90% PoW
10% PoS

This ratio will change again after the release of MPC phase 2 which will include dPoS mining, but PoS mining will probably remain the less frequent type of mining. This is mostly due to the complexity of PoS mining for users: you need at least 2,000 ETP, you have to use the full node wallet and you need to keep your computer running and the wallet open while mining.

Those constraints make dPoS much more convenient to use: once you vote for a delegate, via the lightwallet for instance, you can turn off your computer and let the delegate handle the mining for you.

Then why do we need 3 consensus? The main reason is to avoid a 51% attack. Currently, an attacker could target most of the PoW blockchains for quite a low cost thanks to the current low difficulty of mining. He only needs to make a deposit on an exchange, prepare a chain of X blocks in a row, and once the deposit is credited on the exchange revert all the blocks that follow his deposit by publishing his own longer chain. Which is exactly what happened to ETC a few weeks ago.

With 3 consensus, the attacker would have to create the 3 kinds of blocks in order to create a chain long enough to be approved on an exchange and then revert it. In such a situation, the attacker will need a lot of computer power for the PoW blocks, be a delegate or bribe elected delegates for the dPoS blocks and finally own enough ETP for the PoS blocks. The triple consensus makes this type of attack extremely difficult and very costly to put in place.

How does it work?

But let’s focus on the PoS mining. First you will need to create an Avatar if you don’t already have one, since it is necessary for the different steps of PoS mining. Then you can start mining using the full node wallet (also called desktop wallet), in the Mining section.

The PoS mining page gives you information about the requirements

There are 2 requirements in order to be able to create a block:

1: Lock ETP
You need to lock at least 1,000 ETP, for at least 24,000 blocks (approximately 1 week). It’s important to note that these 1,000 ETP have to be locked in 1 time: doing several locks of 500 ETP will not validate this requirement. It requires 1 lock transaction of 1,000 ETP or more.
Also the last 1,000 blocks before the unlock are excluded. It means that if you lock your ETP for 24,000 blocks, you will only be able to mine during the 23,000 first blocks. If you lock for 48,000 blocks, you will be able to mine for 47,000 blocks etc…

You can lock your ETP here

Finally, the ETP previously locked via the deposit function do not validate this condition: those ETP were already rewarded by the deposit interests, and can’t be used for PoS mining. Only ETP locked via the new lock function introduced in MPC, without interests, can validate it.

2: Available ETP
Then your chances to mine a block are defined by the number of outputs you have that are more than 1,000 ETP, that we call “Votes”. Outputs are basically the ETP you receive, so if you receive 2 transactions of 500 ETP you will have 2 outputs available to spend. But in that case you will not have any votes, since none of the outputs reach the 1,000 ETP threshold. At the opposite, if you receive 1 transaction of 2,000 ETP, you will only have 1 vote whereas you could have 2 votes with this amount.

It’s also important to notice that 1 output of 2,000 ETP will give a bit more chances to find a block than 1 output of 1,000 ETP, but less than 2 outputs of 1,000 ETP . Indeed, the chances to mine a block vary according to the value of the output, but this calculation is not proportional and decreases rapidly. So the best chances to mine PoS are to keep as many outputs as possible just above 1,000 ETP.

This is what the “Optimize” option of the wallet will do for you. It will simply send your ETP to yourself but split into outputs of exactly 1,000 ETP, to guarantee the highest efficiency. It will show you the number of votes you currently have, and how many you can get by reorganizing your outputs.

How to optimize your PoS mining

You probably also noticed that there are “pending votes”. A pending vote is a vote that has been spent recently, in a range going from 500 to 1,000 blocks (from 4 to 8 hours). So if an output is spent, if you just received the transaction for instance, its aging will go to 0 and it will be displayed as a pending vote. After 500 to 1,000 blocks, it will become available to mine again. The exact aging requirement depends on the PoS difficulty: when there are more PoS miners it will increase till the maximum of 1,000 blocks, while when there are less PoS miners it will decrease to the minimum of 500 blocks.

It’s also important to note that optimizing your votes will send all your ETP to yourself, so this will set back the aging of all your votes to 0. You will then have to wait a few hours to be able to mine again. So try not to use this option too often, and keep this option for when it is really worth it.

The transaction created via the Optimize page, splitting the ETP into outputs of 1,000 ETP

Mining a PoS block will also bring back the aging of the vote used to 0, so after finding a block, this one vote will not be available for mining for the next few hours.

These 2 conditions bring the very minimum amount of ETP required to do PoS mining to 2,000 ETP: 1,000 locked and 1,000 available to have at least 1 vote.

Start mining

Once the requirements are reached, the description on the right will show you till which block the first requirement is fulfilled, and the number of votes you have. After clicking on Start mining, you will see the mining information of your Avatar. Don’t forget to select a MST to mine, it does not cost you anything and you will receive both ETP and the selected MST as a reward when you find a block.

Since finding a block creates a new transaction in your wallet, you will receive a new transaction notification each time you find a PoS block.

While 51% attacks are becoming a very serious threat to PoW blockchains, Metaverse Pillars of Creation will implement double and triple consensus in order to guarantee the security of Metaverse. The new PoS and future dPoS consensus will bring an additional level of complexity and highly increase the cost of an attack, while giving the opportunity to ETP holders to actively participate in the security of the blockchain.

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