Apparently it's "Commutative Supersingular Isogeny Diffie–Hellman," and the tl;dr is that it's a form of post-quantum DH, i.e. DH that is secure against the sor

Apparently it's "Commutative Supersingular Isogeny Diffie–Hellman," and the tl;dr is that it's a form of post-quantum DH, i.e. DH that is secure against the sort of quantum attacks that current DH systems (i.e. RSA and ECDH) are vulnerable to. More details: https://csidh.isogeny.org https://csidh.isogeny.org