Hey MrXOR! First off, thanks for posting this link to HN! Second, the VDF used here leverages RSA groups, while the Chia implementation uses Class groups. These

Hey MrXOR! First off, thanks for posting this link to HN! Second, the VDF used here leverages RSA groups, while the Chia implementation uses Class groups. These two VDFs are compared here: https://crypto.stanford.edu/~dabo/pubs/papers/VDFsurvey.pdf https://crypto.stanford.edu/~dabo/pubs/papers/VDFsurvey.pdf. Both the VDFs are subject to hardware and algorithmic speedups which will not impact the security of their use as long as these are taken into account. If you are interested in learning more about VDFs I would recommend looking at this collaborative project by Ethereum and Filecoin: https://vdfresearch.org/ https://vdfresearch.org/.