Staking

Begin your staking journey with Polimec by delegating your PLMC to the collator(s) of your choice. To delegate your PLMC, visit Polimec's staking dashboard.

Staking Metrics

• Block Time: ~12 seconds

• Minimum Delegation: 50 PLMC*

• First Rewards Payout Delay: ~12 hours (3,600 blocks or 2 rounds)

• Round Duration/Rewards Payout Frequency: ~6 hours (1,800 blocks or 1 round)

• Rewards Payout: 90% to delegators and 10% to collators

• Unstaking Period: ~168 hours/7 days (50,400 blocks or 28 rounds)

• Maximum Delegators per Collator: 300

*The minimum delegation of 50 PLMC may vary depending on the number of delegators per collator. This is subject to delegator exhaustion, with a current cap of 300 delegators per collator.

Staking on Polimec

Parachains like Polimec can benefit from Polkadot’s security architecture by introducing collators. Akin to validators on the Relay Chain, in parachain networks, collators play a critical role in maintaining the parachain’s functionality by aggregating transactions from users on the parachain and generating for Relay Chain validators.

For this purpose, collators maintain a full node for the Relay Chain and another one for the corresponding parachain. This enables collators to retain all necessary information to author new blocks and execute transactions. In the normal course of operations, transactions are collated and executed to produce an unsealed block, which is furnished, along with a proof-of-validity (PoV), to one or multiple validators responsible for proposing a parachain block.

Similar to nominated proof-of-stake (NPoS), where DOT holders can participate as nominators, Polimec’s delegated proof-of-stake (DPoS) mechanism enables PLMC holders to act as delegators. By delegating PLMC to collators, delegators are eligible to receive rewards in PLMC in return. This process, referred to as staking, closely mirrors the procedure for DOT holders on the Relay Chain. During staking PLMC, a staking lock is activated, restricting transfers, evaluations, and participation in projects using the staked PLMC.

Staking Rewards

Staking rewards for collators and their delegators are paid out in PLMC on a round-by-round basis. The effective staking rewards rate is determined by the amount of PLMC staked in relation to the total supply. The more PLMC staked, the less staking rewards per staked PLMC.

Each round, collator candidates are selected to join the active set, which is capped at 10 collators. If there are 10 or fewer collators, a selected candidate of the active set needs only a minimum self stake of 20,000 PLMC. Conversely, if more than 10 collators compete for the active set, only the 10 collators with a self stake of minimum 20,000 PLMC and with the highest total delegation (self stake plus delegator stake) become the selected candidates of the active set.

Each round consists of 1,800 blocks, distributed equally among the active collators using round-robin scheduling. Every block produced by a collator earns them 20 points for the round, with a maximum of per round. A collator’s share of the PLMC distributed each round is determined by dividing their score by the total points.

Calculation Example - Staking

Let’s assume that 750 PLMC is distributed for a round on Polimec. Recall that 90% is paid out to delegators and 10% to collators. Thus, is distributed to collators. Since the blocks are distributed equally among the active collators, and there were 10 active collators, each had the opportunity to create a maximum of during this round. However, collators can create more than 180 blocks in a round, particularly when other collators in the active set miss their blocks.

Collator	Generated Blocks	Missed Blocks
Collator 1	145	35
Collator 2	179	1
Collator 3	175	5
Collator 4	189	0
Collator 5	170	10
Collator 6	189	0
Collator 7	189	0
Collator 8	188	0
Collator 9	188	0
Collator 10	188	0

A total of 51 blocks - and thus 1,020 points - were reassigned. The Rewards Payout per Collator is calculated as:

${\text{(1) Rewards Payout per Collator}}=\frac{\text{Round Points of Collator}}{\text{Total Round Points}} \times ({\text{Total Round Allocation (PLMC)} \times {\text{0.1}}})$

${\text{e.g. Collator 1}}=\frac{\text{2,900}}{\text{36,000}} \times ({\text{750 PLMC} \times {\text{0.1}}})={\text{6.04 PLMC}}$

To calculate the Rewards Payout per Collator, one must divide the points earned by each collator in that round by the total round points. Then, multiply this figure by the 10% allocation designated for collators, i.e. 75 PLMC. This means that a collator’s PLMC payout depends solely on their performance - specifically, on not missing any blocks - and is not determined by their total PLMC delegations once they have joined the active set.

However, the Rewards Payout for Delegators has not been considered yet. Since they constitute 90%, 675 PLMC is distributed to delegators. The Rewards Payout to Delegators is calculated as:

${\text{Rewards Payout to Delegators}}=({\text{Total Round Allocation (PLMC)} \times {\text{0.9}}})$

${\text{e.g. Rewards Payout to Delegators}}=(\text{750 PLMC} \times {\text{0.9}})={\text{675 PLMC}}$

To calculate the Rewards Payout to Delegators, one must multiply the total round PLMC allocation by the 90% allocation designated for delegators, i.e. 675 PLMC.

In a next step, the Rewards Payout per Delegator is calculated and distributed pro rata among all delegators of that collator:

${\text{Rewards Payout per Delegator}}=\frac{\text{Round Points of Collator}}{\text{Total Round Points}} \times ({\text{Total Round Allocation (PLMC)} \times {\text{0.9}}}) \times \frac{\text{Delegator Stake per Collator (PLMC)}}{\text{Total Stake per Collator (PLMC)}}$

For simplicity, let's assume that Collator 1 has only 2 delegators - Delegator 1 and Delegator 2 - each of whom delegated an equal amount of 15,000 PLMC. Therefore, calculating the Rewards Payout per Delegator would involve:

${\text{e.g. Rewards Payout Delegator 1}}=\frac{\text{2,900}}{\text{36,000}} \times {\text{675 PLMC}} \times \frac{\text{15,000 PLMC}}{\text{50,000 PLMC}}={\text{16.31 PLMC}}$

It is important to note that the collators have a self stake of, i.e. 20,000 PLMC in the delegator allocation, and thus in Rewards Payout to Delegators. However, this portion of the rewards belongs to the collator. Therefore, considering the ratio of self stake to delegator stake, the Final Rewards Payout per Collator is calculated as:

${\text{Final Rewards Payout per Collator}}=\frac{\text{Round Points of Collator}}{\text{Total Round Points}} \times ({\text{Total Round Allocation (PLMC)} \times {\text{0.9}}}) \times \frac{\text{Self Stake (PLMC)}}{\text{Total Stake per Collator (PLMC)}}+{\text{(1)Rewards Payout per Collator}}$

${\text{Final Rewards Payout Collator 1}}=\frac{\text{2,900}}{\text{36,000}} \times {\text{675 PLMC}} \times \frac{\text{20,000}}{\text{50,000}}+{\text{6.04 PLMC}}={\text{21.75 PLMC}}+{\text{6.04 PLMC}}={\text{27.79 PLMC}}$

The following table provides these calculations, with the delegator stakes being assumptions.

Collator	Self Stake	Delegators Stake	Total Stake per Collator	Rewards Payout Collator	Rewards Payout Delegators
Collator 1	20,000 PLMC	30,000 PLMC	50,000 PLMC
Collator 2	20,000 PLMC	20,000 PLMC	40,000 PLMC
Collator 3	20,000 PLMC	0 PLMC	20,000 PLMC
Collator 4	20,000 PLMC	0 PLMC	20,000 PLMC
Collator 5	20,000 PLMC	0 PLMC	20,000 PLMC
Collator 6	20,000 PLMC	30,000 PLMC	50,000 PLMC
Collator 7	20,000 PLMC	10,000 PLMC	30,000 PLMC
Collator 8	20,000 PLMC	0 PLMC	20,000 PLMC
Collator 9	20,000 PLMC	0 PLMC	20,000 PLMC
Collator 10	20,000 PLMC	100,000 PLMC	120,000 PLMC

When all the numbers are added up, the following final rewards payout for collators and delegators emerge:

Collator	Final Rewards Payout per Collator	Rewards Payout Delegators	Total Rewards Payout
Collator 1		32.63 PLMC	60.42 PLMC
Collator 2		33.56 PLMC	74.58 PLMC
Collator 3		0 PLMC	72.92 PLMC
Collator 4		0 PLMC	78.76 PLMC
Collator 5		0 PLMC	70.83 PLMC
Collator 6		42.52 PLMC	78.75 PLMC
Collator 7		23.62 PLMC	78.75 PLMC
Collator 8		0 PLMC	78.33 PLMC
Collator 9		0 PLMC	78.33 PLMC
Collator 10		58.75 PLMC	78.33 PLMC

If a collator fails to perform their required functions, no rewards will be distributed, including for their respective delegators. If a parachain block is invalid, validators will reject it, and the affected collators will lose further validator backing. This differs from validators and their nominators on the Polkadot Relay Chain, as they face slashing risks for erroneous or malicious behavior. Hence, there is no slashing for collators on Polimec.

Relationship between the Polimec parachain and the Polkadot Relay Chain: