On 27/09/10 11:12, David Smith wrote: > Daniel Kahn Gillmor wrote: >> On 09/24/2010 09:54 AM, David Shaw wrote: >>> It won't work with the current generation of OpenPGP smartcards. It also >>> will be dreadfully slow if you (or someone you are communicating with) ever >>> uses the key on a small machine (think smart phone). If you are usually on >>> a "full power" computer, then they generally have the CPU to spare for this >>> sort of thing, and you'll rarely if ever notice a difference. >> >> i'm curious to see some quantitative data about what "dreadfully slow" >> means. > > Not truly "quantitative, but I notice a significant difference between > encrypting emails to people with 1024-bit keys vs people with 4096-bit > keys. I'd say that the difference is in the order 3-6 seconds. > > I'm running GnuPG 1.4.x on a Sun Ultra10 with a 500 MHz CPU and 1 GB > RAM. Yes, I know it's old. :-) > > We're forced to use 4096-bit keys because some of our customers require it. >
I did some quick tests on Nokia N900 (600 MHz ARM CPU), with gnupg 1.4.6, here is what I got: Encrypting and signing, 2048 bit RSA keys: real 0m 2.50s user 0m 0.50s sys 0m 0.02s Decrypting and verifying, 2048 bit RSA keys: real 0m 1.74s user 0m 0.41s sys 0m 0.04s Encrypting and signing, 4096 bit RSA keys: real 0m 3.58s user 0m 1.92s sys 0m 0.06s Decrypting and veryfying, 4096 bit RSA keys: real 0m 3.80s user 0m 1.89s sys 0m 0.03s Is one second considered a rule of thumb limit? That would mean that 4096 keys are not suitable for widespread use yet. _______________________________________________ Gnupg-users mailing list Gnupg-users@gnupg.org http://lists.gnupg.org/mailman/listinfo/gnupg-users
