djb and Tanja Lange
The world is finally catching on to the urgency
of deploying post-quantum cryptography:
cryptography designed to survive attacks by quantum computers.
NIST's post-quantum competition is in full swing,
and network protocols are exploring post-quantum extensions.
This talk will take the audience on a journey
through selected recent highlights
from the post-quantum world.
Post-quantum cryptography has become one of the most active
areas in cryptography,
trying to address important questions from potential users.
Is post-quantum cryptography secure?
In the first ten months of this year
we have seen several serious breaks
of submissions to the NIST competition.
At this point, out of the original 69 submissions,
13 are broken and 8 are partially broken.
Are the remaining 48 submissions all secure?
Or is this competition a denial-of-service attack
against the cryptanalysis community?
NIST will select fewer candidates for the 2nd round,
but it is not clear whether there is an adequate basis
for judging security.
Does post-quantum cryptography provide
the functionality we expect from cryptography?
For example,
the original Diffie-Hellman system
provides not just encryption
but also more advanced features
such as non-interactive key exchange
(not provided by any NIST submissions)
and blinding.
The era of post-NIST post-quantum cryptography has begun
with the exciting new CSIDH proposal,
which has non-interactive key exchange
and is smaller than any NIST submission,
but uses more CPU time and needs much more study.
Is post-quantum cryptography small enough?
Even for network protocols that rely purely on encryption,
integration remains a major problem
because of the bandwidth requirements of most post-quantum systems,
especially the post-quantum systems
with the strongest security track records.
Experiments with integration of post-quantum cryptography into TLS
have focused on encryption without post-quantum authentication.
A new generation of network protocols
has been designed from the ground up for full post-quantum security.
Is post-quantum cryptographic software fast enough,
and is it safe to use?
Adding post-quantum cryptography
to the cryptographic software ecosystem
has produced a giant step backwards in software quality.
Major areas of current activity include
software speedups,
benchmarking,
bug fixes,
formal verification,
patent avoidance, and
development of post-quantum software libraries
such as Open Quantum Safe and libpqcrypto.
The talk will be given as a joint presentation
by Daniel J. Bernstein and Tanja Lange.