A comparison of pool reward types. You'll always see the reward distribution type listed either on the pool's homepage or in the pool's "About" section.
Most common:
Much less common:
- Prop. - Proportional. The most simple reward type, and the most common. When a block is found the reward is distributed among all workers proportionally to how many shares each miner has found.
- PPS - Pay Per Share. Each submitted share is worth certain amout of coins. Since finding a block requires <current difficulty> shares on average, a PPS method with 0% fee would be 3.0 ETH divided by <current difficulty>. It is risky for pool operators, hence the fee is typically higher.
- PPLNS - Pay Per Last N Shares. Similar to proportional, but instead of looking at the number of shares since the last block, it looks at the last N shares (an integer defined by the pool), regardless of when the last block was found.
Much less common:
- POT - Pay-On-Target. A high-variance PPS scheme that pays based upon the difficulty of work returned to the pool rather than the difficulty of work served by the pool.
- PPLNSG - Pay Per Last N Groups (or shifts). Similar to PPLNS however shares are grouped into "shifts" which are paid as a whole.
- SMPPS - Shared Maximum Pay Per Share. Similar to PPS, but never pays more than the pool earns.
- RSMPPS - Recent Shared Maximum Pay Per Share. Like SMPPS, but the system prioritizes the most recent miners first.
- Score - Score-based system: a Prop reward scheme, but weighed by time submitted. Shares submitted later in the round are worth more than shares found early in the round, incentivizing miners to stay through unlucky blocks. Rewards are calculated proportionally to scores as opposed to shares.
- FPPS - Full Pay Per Share. Similar to PPS but miners are also rewarded some of the transaction fees, minimally increasing the miners' earnings. A standard transaction fee within a certain time period is calculated and distributed according to shares.