card-sized 4 Kbit RSA Smartcard recommendation with 3 slots

Andrew Gallagher andrewg at
Thu Apr 4 17:43:10 CEST 2019

On 04/04/2019 16:10, Peter Lebbing wrote:
> I don't expect 4k RSA to be very snappy, though. You might want to
> reconsider your choice of algorithm and/or length.

On the v2.1 Zeitcontrol cards, 4096 bit RSA takes a couple of seconds
per operation. This is fine if you're just doing bits and pieces, but
when using it heavily, e.g. as an ssh auth method over ansible, it can
get *very* sluggish.

Andrew Gallagher

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