file encryption and integrity check

[Vladimir Doisan]

Yes, I did exactly the same for my encrypted backups, only I chose
Twofish due to speed advantage (TW256 - 16.2 mbps vs. AES256 - 12.6
mbps). With compression enabled - encryption speed was within 0.5 mbps
across all ciphers at around 12 mbps.
I did switch over to public key encryption last month.

Some benches
(this is on single Xeon 2.8 EM64T, 1 Gig RAM with RAID5 running Gentoo
in two separate 64 and 32 bit installs)
GnuPG 1.4.2 Benchmarks (symmetric encryption, no compress)

512 MB backup file
                          GnuPG-64         |         GnuPG-32
---------------------------------------------------------------------------
twofish (256)        33.5s (15.3 mbps)     |         32.2s (15.9 mbps)
aes (128)            33.3s (15.4 mbps)     |         34.5s (14.8 mbps)
aes192               35.0s (14.6 mbps)     |         33.8s (15.1 mbps)
aes256               37.5s (13.7 mbps)     |         36.8s (13.9 mbps)
blowfish             52.3s (9.8 mbps)      |         52.7s (9.7 mbps) 
CAST5                26.9s (19.0 mbps)     |         25.0s (20.5 mbps)
3DES                 48.3s (10.6 mbps)     |         47.0s (10.9 mbps)


4.0 Gig backup file
                          GnuPG-64        |           GnuPG-32
---------------------------------------------------------------------------
twofish (256)        253s (16.2 mbps)     |         257s (15.9 mbps)
aes (128)            310s (13.2 mbps)     |         278s (14.7 mbps)
aes192               318s (12.8 mbps)     |         288s (14.2 mbps)
aes256               325s (12.6 mbps)     |         311s(13.2 mbps)



OpenSSL 0.9.7-r2 Benchmarks (probably for another topic - it blows GnuPG
out of the water in terms of speed)

512MB backup file
                        OpenSSL-64         |         OpenSSL-32
-----------------------------------------------------------------------------
aes (128)            14.0s (36.6 mbps)     |         17.9s (28.6 mbps)
aes192               15.1s (33.9 mbps)     |         19.2s (26.7 mbps)
aes256               16.8s (30.5 mbps)     |         18.0s (28.4 mbps)
blowfish             13.3s (38.5 mbps)     |         13.0s (39.4 mbps) 
CAST5                20.5s (25.0 mbps)     |         16.8s (30.5 mbps)
3DES                 39.5s (13.0 mbps)     |         32.2s (15.9 mbps) 


4.0 Gig backup file
                       OpenSSL-64         |         OpenSSL-32
---------------------------------------------------------------------------
aes (128)            164s (25.0 mbps)     |         163s(25.1 mbps)
aes192               166s (33.9 mbps)     |         168s(24.4 mbps)
aes256               173s (23.5 mbps)     |         179s (22.9 mbps)