The post-quantum future: challenges and opportunities

Quantum computers pose a threat to modern cryptographic mechanisms, but the cryptographic community has designed new mechanisms to safeguard against this disruption. The most important security and privacy properties to protect in the face of a quantum computer are confidentiality and authentication. Changing the key exchange of the TLS handshake is simple; changing the authentication of TLS, in practice, is hard. Middleboxes and middleware in the network can be slow to upgrade, hindering the rollout of new protocols. The migration to post-quantum cryptography is not only about the technical changes but is dependent on how the Internet works as an interconnected community that needs coordination and collective willingness to change systems.