A Review on Generating Random Numbers in Decentralised Environments

Recent advances in blockchain gained significant social attention, mainly due to substantial price fluctuations of Bitcoin and Ethereum cryptocurrencies. By its design, blockchain is an open, distributed ledger that can record transactions between two parties efficiently and in a verifiable and permanent way, providing solutions for many complex tasks without third party involvement. To achieve that, they employ a set of Byzantine Fault-tolerant consensus algorithms that require the implemented logic to be deterministic. The lacking source of randomness is a consequential limitation since many application domains, like games, lotteries, or random elections, require random sources. Given the Byzantine Fault-tolerance, generating random numbers should also be publicly-verifiable and tamper-resistant, but still hold the premises of being unpredictable.In this paper, we will provide an overview of the current research surrounding pseudo-random number generation on a decentralized network that satisfies those requirements.