Deploying Post Quantum Cryptography on Newspace Satellites

We describe and implement a new key exchange protocol combining both Post Quantum Cryptography (PQC) and Elliptic Curve Cryptography (ECC). The protocol is designed to allow for authenticated key exchanges with a single satellite. The Triple Key Encapsulation Mechanism (KEM) protocol is designed to be secure against both classical and quantum attackers and retains its full security even if one of the two cryptographic schemes is broken. The protocol was implemented on two generations of Berlin Space Technology (BST) On Board Computers (OBC) and tested on the AFR small satellite in low earth orbit using an In Orbit Demonstrator (IOD) board of the new BST OBC. We discuss some of the challenges PQC poses for low performance systems and satellites in general and outline some of the strategies employed to overcome them.