A Survey on the Security and Privacy of Blockchain Systems

Abstract

Since when bitcoin make an entry in cryptocurrency which is based on blockchain technology gets so much popularity just from initial phase itself, now most of the cryptocurrency are moving towards blockchain framework and using different hashing function. In this advancement most of the works are now using blockchain technology from cryptocurrency to smart online retails platforms which has been used by Walmart. since its going to be most used term and popular technology most of the attackers are targeting and just by using some loopholes and any other technical glitches or any other way they are attacking over this technology. since its going to be future and everyone is concerned for its security and privacy, here we did a good comparison of many attacks already did on this blockchain frameworks and we summarize this attacks and we tried to give our own opinion to make it more reliable and flexible. Key Words: Consensus, PoW, PoS, PoL, PoI, Bloch Chain,