The Book of Bitcoin

Mining Pools

AntPool

The mining pool AntPool is a Chinese mining pool run by the Bitmain corporation. Although ostensibly a public mining pool, BitMain actually operates the vast majority of the pool's hashing power.

AntPool blocks carry a "Mined by AntPool" signature

BitMinter

BitMinter is a mining pool that has been operating since June of 2011.

BitMinter is operated by Geir Harald Hansen, and has a coinbase signature "BitMinter".

CKPool

CKPool is a Stratum based mining pool run by the developer of CGMiner, a popular ASIC mining software project. It started operation in September of 2014, using a coinbase signature "ckpool/Kano".

Eligius

Eligius, also known as Luke-Jr's Pool, is a registration-free, no-fee mining pool started in April of 2011 by the Core developer Luke-Jr, but has been run by Wizkid057 since October of 2012. Blocks are published using the signature "Eligius".

F2Pool

F2Pool, also known as Discus Fish, is a China based mining pool that has been in operation since May of 2013 and has servers in various Chinese cities as well as in the US. F2Pool publishes blocks using the coinbase signature 七彩神仙魚, the handle of one of their operators. Translated, the nickname means Discus Fish, hence the pool alias.

F2Pool also mines altcoins: Dogecoin, Ethereum, Huntercoin, Litecoin, and Namecoin are offered.

GHash.IO

The GHash.IO mining pool is the mining pool of the CEX.IO exchange. The pool has been operating since July of 2013, offering Bitcoin, Dogecoin, Litecoin and Namecoin pooled mining.

Double Spending

GHash has had a troubled history being a good mining citizen. In November of 2013, it was reported that GHash was deliberately executing double spend attacks to defraud a gambling site called BetCoin Dice.

Excessive Share

In June of 2014, GHash controlled a very large share of the network's hashing power, sparking fears of a potential fifty-one percent attack. While a miner has only a marginal chance of succeeding at a double spend with a minority hashing power stake in the network, with a fifty-one percent share a miner can execute a double spend with one hundred percent certainty.

Confidence was shaken in the network, Core Developer Peter Todd publicly announced that the problem was so serious he was liquidating half of his Bitcoin savings. In response GHash deliberately backed off from their majority share, although it's impossible to know if they simply redirected their hashing power at other pools.

Slush Pool

Slush Pool, also known as Bitcoin Pooled Mining, is a mining pool that was started November 27, 2010 and has been mining blocks since December 16, 2010.

On November 11, 2012 Slush's pool mined the two hundred and ten thousandth block, which is notable for being the first block of the first half point of the block subsidy. Instead of the original fifty coin reward, Slush's pool was rewarded twenty-five coins for the solution.

The mining pool uses a coinbase signature "/slush/", and it follows a philosophy of being responsive to individual hashers preferences.