Cex.io is a cloud mining provider, which contributes to the Bitcoin network with hashing power. Participants are rewarded with shares of the block rewards and transaction fees. A share is your percentage of the overall hashing power, so when a block is found by your cloud mining hashing power you receive mining payouts equivalent to your share of the overall hashing power.

If for any reason you fail to receive shares for your hashing power or the service suffers downtime we reward you with additional shares proportional to the downtime to compensate for the disruption in service.

This is how the process works:

A shift is a 10 minute period where hashing power is used to find a new block on the Bitcoin network. If the mining pool was down for 30 minutes, this is about 3 shifts, during which no shares were submitted from your account. If the pool or your account did not experience disruption, you would have received 3 shifts worth of shares. What happens is the shares you did not receive are added to the next shift. So, the following shift you will receive 4x shares, 1 for normal operation, and 3 additional for the disruption in service. Once a block is solved after the downtime and compensation are distributed, you will receive the same payment as if the downtime didn’t occur, due to our PPLNS or “Pay per last N shares” system which automatically compensates for downtime.
For example, if you have 2 normal shifts, 3 shifts of downtime, one shift of 4x shares as compensation followed by 4 more shifts of normal operation with PPLNS, it will be counted as 10 normal shifts, also called a full round. So, in the case of downtime you will receive normal payout proportional to your shares minus the usual maintenance cost.
We hope this answers your questions about downtime or service disruptions as our goal is to guarantee 100% utilization of the hashing power you own. Compensation is only offered for cloud mining obtained through Cex.io and not for personal hardware contributed separately to the Ghash.io pool. If you have any additional questions feel free to contact our support staff.

By Gavin Knight for CEX.IO