XCELLENCE IN NETWORKING
by Alexander Standridge MSc Candidate California State University, Northridge astandridge@gmail.com Calvin Ho MSc Candidate California State University, Northridge calvin.ho.67@my.csun.edu Shahnam Mirzaei Assistant Professor California State University, Northridge shahnam.mirzaei@csun.edu Ramin Roosta Professor California State University, Northridge ramin.roosta@csun.edu
The integration of programmable logic with a processor subsystem in one device allows for the development of an adaptable and affordable Bitcoin miner. itcoin is a virtual currency that has become increasingly popular over the past few years. As a result, Bitcoin followers have invested some of their assets in support of this currency by either purchasing or “mining” Bitcoins. Mining is the process of implementing mathematical calculations for the Bitcoin Network using computer hardware. In return for their services, Bitcoin miners receive a lump-sum reward, currently 25 Bitcoins, and any included transaction fees. Mining is extremely competitive, since network rewards are divided up according to how much calculation all miners have done. Bitcoin mining began as a software process on cost-inefficient hardware such as CPUs and GPUs. But as Bitcoin’s popularity has grown, the mining process has made dramatic shifts. Early-stage miners had to invest in power-hungry processors in order to obtain decent hash rates, as mining rates are called. Although CPU/GPU mining is very inefficient, it is flexible enough to accommodate changes in the Bitcoin protocol. Over the years, mining operations have slowly gravitated toward dedicated or semi-dedicated ASIC hardware for optimized and efficient hash rates. This shift to hardware has generated greater efficiency in mining, but at the cost of lower flexibility in responding to changes in the mining protocol. An ASIC is dedicated hardware that is used in a specific application to perform certain specified tasks efficiently. So although ASIC Bitcoin miners are relatively inexpensive and produce excellent hash rates, the trade-off is their inflexibility to protocol changes. Like an ASIC, an FPGA is also an efficient miner and is relatively inexpensive. In addition, FPGAs are more flexible than ASICs and can adjust to Bitcoin protocol changes. The current problem is to design a completely efficient and fairly flexible mining system that does not rely on a PC host or relay device to connect with the Bitcoin Network. Our team accomplished this task using a Xilinx® Zynq®-7000 All Programmable SoC.
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THE BIG PICTURE To accomplish our goal of implementing a complete mining system, including a working Bitcoin node and a miner that is both efficient and flexible, we needed a powerful FPGA chip not only for flexibility, but also for performance. In addition to the FPGA, we also needed to use a processing engine for efficiency. Third Quarter 2013
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