Pools were often hacked by hackers, because they knew that there was always a lot of money on their wallets. It happened that the pool administrators themselves showed bad faith (for example, they disappeared with the money and closed the server). To exclude such possibilities, a decentralized P2Pool was invented, the program code of which is open for review and modification. Each P2Pool node (node) is only one of the elements of the system. Participants should stay on one of the nodes to receive the maximum reward. It is not profitable to "jump" from one node to another here. P2pool has many advantages over the classic pool, first of all, it is anonymity - you do not need to enter your personal data, you only need valid wallet and email addresses to get started. The decentralized structure provides 100% protection against DDoS, and if one of the nodes "falls off", the results will be automatically picked up by another node. A commission is distributed among P2Pool miners, which further increases their income. Regular pool owners often keep commissions to themselves.
Merged mining - mining of several cryptocurrencies
Merged mining is the joint mining of several cryptocurrencies at once. Those hash solutions that were not useful when calculating the signature of a Bitcoin block are calculated for other cryptocurrencies configured for joint mining. Among the concurrently mined forks are Namecoin, Devcoin, IxCoin, I0Coin. All of them are of great complexity and low exchange rates. Some Bitcoin pools involve co-mining one or more forks, usually Namecoin. It gives miners 1-2% additional income. Therefore, when choosing a pool, pay attention to the possibility of using merged mining.
LTC & DOGE
Co-mining is supported by Litecoin and Dogikoin. Since both cryptocurrencies use the same Scrypt algorithm, there are no technical problems with this. Anyone who mines Litecoin receives an additional amount of Dogocoin and vice versa.
Multi-coin and multipools
There are pools not only for mining bitcoins, but also for other cryptocurrencies. Of the alternatives, Litecoin (Litecoin, LTC) is the most popular. Moreover, there is also specialized equipment (ASIC) for the Scrypt algorithm. In its classic form, the pool is a server for connecting devices that perform calculations according to one algorithm - for Bitcoin, this is double SHA256. But over time, multi-coin pools also appeared. Miners who want to mine several cryptocurrencies are connected to them, switching to mining the most profitable at the moment. The miner performs all switches manually. To switch to another altcoin, it is enough to change the TCP port in the settings of the mining program. In fact, a multi-coin pool differs from ordinary pools only in that the user does not need to create multiple accounts for each separate fork. All mined coins are transferred by a pool to one account, from where they are manually or automatically paid to the miner's wallets. The next development step was multipools. Their main advantage is that mining automatically switches to mining the currently most profitable cryptocurrency. This takes into account the complexity, the price of the coin on the exchanges and many other factors. On multipools, as a rule, altcoins can be mined using several common hashing algorithms: SHA256, Scrypt, Scrypt-N, X11-13-15, etc. It must be said that many modern cryptocurrencies - for example, Ethereum and DASH - use graphics processing units (GPUs) for mining. There are also Bitcoin forks that can only be mined on CPUs. But, regardless of the equipment used, the principle remains the same: mining in pools is replacing solo mining, which significantly reduces the potential for decentralization, since the pool actually disposes of the power of the connected miners at its discretion. This includes, for example, a pool operator can include in its blocks only the transactions it needs. The strategic goal of enthusiasts for decentralized currencies should be to improve the technology of distributed mining so that anyone can use it - as easy as connecting to one of the usual pools.