Supersingular isogeny key exchange

Supersingular isogeny Diffie–Hellman key exchange (SIDH or SIKE) was an insecure proposal for a post-quantum cryptographic algorithm to establish a secret key between two parties over an untrusted communications channel. It is analogous to the Diffie–Hellman key exchange, but is based on walks in a supersingular isogeny graph and was designed to resist cryptanalytic attack by an adversary in possession of a quantum computer.

Source: Wikipedia — Supersingular isogeny key exchange (CC BY-SA 4.0)