throughput of GnuPG symmetric ciphers

Ryan Malayter malayter at
Wed Aug 3 19:07:59 CEST 2005

On 8/3/05, Henry Hertz Hobbit <hhhobbit7 at> wrote:
> Given the size of the files that you are encrypting, I would strongly
> advise going with the Eden chip rather than a software based solution...

I actually found an open-source tool, 7-zip, that includes AES-256
encryption functionality. For whatever reason, it runs several times
faster than GnuPG in software.

Fast enough, in fact, that the removable hard disk devices have become
the limiting factor in the system (the 7-zip process only uses 70% CPU
on a 2.4 GHz P4). The code is open-source, and it uses a salted +
iterated SHA256 hash to produce the AES key from a pass phrase. The
AES implementation is Gladman's well-known and fast C++ code.

Looking at the source, I haven't figured out whether it uses ECB or
CFB mode yet; the 7-zip code is rather light on comments. I am
assuming ECB, which should be fine for my application.

See for more details.

Thanks for all the help.

All problems can be solved by diplomacy, but violence and treachery
are equally effective, and more fun.

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