> For the complete documentation index, see [llms.txt](https://tokens-economy.gitbook.io/consensus/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://tokens-economy.gitbook.io/consensus/chain-based-pbft-and-bft-based-proof-of-stake/ouroboros.md).

# Ouroboros

A variation of Proof-of-stake(with rigorous security guarantees) used by Cardano.

## Used in

* Cardano

## Read more

* [Wikipedia](https://eprint.iacr.org/2016/889.pdf)
* [Ouroboros: A provably secure proof-of-stake blockchain protocol](https://pdfs.semanticscholar.org/1c14/549f7ba7d6a000d79a7d12255eb11113e6fa.pdf). Kiayias A, Russell A, David B, Oliynykov R. '16.