As a decentralized virtual currrency, Bitcoin has attracted many users since 2008.
Bitcoin is a fully distributed, peer to peer system. For this reason, there is no central server or point of control. Bitcoins are created through a process called mining, which involves looking for a solution to a difficult problem.
Any participant in the Bitcoin network may operate as a miner, using their computer’s processing power to attempt to find solutions to this problem. Every 10 minutes on average, a new solution is found by someone who then is able to validate the transactions of the past 10 minutes and is rewarded with new bitcoins.
Essentially, Bitcoin mining decentralizes functions of a central bank and replaces the need for any central bank. Miners need high computational power for hash processing.
The hashing rate and energy consumption of mining devices are the most important things to earn profit in Bitcoin mining.
Bitcoin mining fully relies on performing double SHA256 operation with structured input and many researchers thought about making hardware optimization for this process without considering specifies of Bitcoin mining.
Only a few researches have been made on SHA256 hashing algorithm optimization focusing on Bitcoin mining application. In this research, to speed up of SHA256 hashing algorithm, implementing the methods proposed in the recent research is aimed.
These techniques could provide important improvement on Bitcoin mining, but not for general SHA256 hashing algorithm. The proposed optimization methods have been implemented on the Xilinx Virtex-7 FPGA board, and we see that these improvement methods are applicable based on the obtained source and power consumption values.
The values collected from the implemented system show us that 7% increase in performance is achieved (the processing time of two SHA256 hash functions used for Bitcoin mining falls to approximately 1.8611 SHA256 time operation).
It is expected that around 7% decrease in electricity consumption, which is the most important restriction step in Bitcoin mining, is possible in 2016, $400 million was spent on electricity consumption for Bitcoin mining and according to this performance increase, $28 million electricity consumption can be saved.
