Overview

The need for digital randomness is paramount in multiple digital applications ([e]voting, lottery, cryptographic parameters, embedded devices bootstrapping randomness, blockchain systems etc) as well in non-digital such as statistical sampling (used for example to check results of an election), assigning court cases to random judges, random financial audits, etc. However, constructing a secure source of randomness is anything but easy: there are countless examples of attacks where the randomness generation was the culprit (static keys, non-uniform distribution, biased output, etc). drand aims to fix that gap by providing a Randomness-as-a-Service network (similar to NTP servers for time, or Certificate Authority servers for CAs verification), providing continuous source of randomness which is:

• Decentralized: drand is a software ran by a diverse set of reputable entities on the Internet and a threshold of them is needed to generate randomness, there is no central point of failure.
• Publicly verifiable & unbiased: drand periodically delivers publicly verifiable and unbiased randomness. Any third party can fetch and verify the authenticity of the randomness and by that making sure it hasn't been tampered with.
• And "private" as well: drand nodes can also deliver encrypted randomness to be used in a local applications, for example to seed the OS's PRNG.

A drand network is operated by a group of organizations around the world that includes Cloudflare, EPFL, Kudelski Security, Protocol Labs, Celo, UCL, and UIUC. You can learn more by visiting the League of Entropy website, where you can also see the random values being generated by the network in real time.