[Cryptography] Some quantum computers might need more power than supercomputers

[Jason Cooper]

On Fri, Jan 09, 2026 at 08:15:26AM +0000, Peter Gutmann via cryptography wrote:
> Jon Callas <jon at callas.org> writes:
> 
> >Some quantum computers might need more power than supercomputers
> 
> The German government (via the BSI) wrote a report on this and estimated that
> it would take 100 days and €4M in electricity to recover a single 2048-bit key
> on a quantum computer that doesn’t exist.  That's one single key.  There are 7
> trillion keys negotiated each year just for TLS web connections.

To be fair, with an eye towards improving your presentation:

Those 7 trillion keys each have metadata associated with them.  Source and
destination IP addresses, timestamps, port numbers.

While there is indeed a virtual sea of keys to recover, there is sufficient
data to reduce it to connections of interest.


thx,


Jason.