Verifiable Delay Functions

@article{Boneh2018VerifiableDF,
  title={Verifiable Delay Functions},
  author={Dan Boneh and Joseph Bonneau and Benedikt B{\"u}nz and Ben Fisch},
  journal={IACR Cryptol. ePrint Arch.},
  year={2018},
  volume={2018},
  pages={601}
}
We study the problem of building a verifiable delay function (VDF). A \(\text {VDF}\)requires a specified number of sequential steps to evaluate, yet produces a unique output that can be efficiently and publicly verified. \(\text {VDF}\)s have many applications in decentralized systems, including public randomness beacons, leader election in consensus protocols, and proofs of replication. We formalize the requirements for \(\text {VDF}\)s and present new candidate constructions that are the… 
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TLDR
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This work constructs a verifiable delay function (VDF) based on groups of unknown order such as an RSA group, or the class group of an imaginary quadratic field, which is very short, and the verification of correctness is very efficient.
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