[OpenAFS] Why is speed of AFS loopback adapter set to 10 Mb, even if physical interface is Gb capable?

Simon Wilkinson sxw@inf.ed.ac.uk
Sun, 25 Apr 2010 21:44:24 +0100


On 25 Apr 2010, at 15:19, Holger Rauch wrote:
> So, my question is: Why is there almost no decrease when using SCP
> with a strong encryption algorithm (compared to plain DES that AFS
> uses) but there is *drastic* decrease in performance with only plain
> DES enabled compared to an unencrypted transfer?

Firstly, as I (and others) have mentioned, OpenAFS doesn't use DES, it =
uses an encryption algorithm called fcrypt, which is a DES derivative.

Secondly, your assumption that weaker encryption algorithms will be =
faster to compute is sadly false. Typical DES implementations are =
significantly slower than AES ones, for example - just compare the =
output from OpenSSL's speed tool.

Cheers,

Simon.