[Box Backup] Box-Backup slow: 0.1 MiB/sec

Magnus Homann boxbackup@fluffy.co.uk
Sun, 13 Aug 2006 18:58:44 +0200


Ben Summers wrote:
> 
> On 9 Aug 2006, at 18:13, Felix E. Klee wrote:
> 
>> At Wed, 9 Aug 2006 17:23:33 +0200,
>> Baltasar Cevc wrote:
>>> Try to check whether the IO on the machine is the problem. My old
>>> backup server (which is a machine with about 2 GHz) had serious
>>> trouble with the whole bunch of tiny files bbstored writes.
>>
>> Thanks for the hint.  I may indeed try that out.  However, first I'd
>> like to know whether it's possible to disable encryption of the
>> transmission channel and, if so, how.
> 
> It's not possible.
> 
>> Also, I'd like to know why the
>> transmission channel is encrypted: After all, the backups themselves are
>> encrypted.  So, additional encryption seems to be superfluous, something
>> for the paranoid.
> 
> The protocol around the backups isn't encrypted. Using SSL gives you
> 
> * Strong authentication
> 
> * Protection from man-in-the-middle attacks
> 
> * And obscures the stuff being transmitted, reducing the information 
> available to an eavesdropper to just quantity and timing.
> 
> The cost is a bit of public key crypto at the beginning of each session, 
> which would need to be done anyway for authentication, and symmetric 
> crypto for all data during the session. The latter is not very processor 
> intensive, and certainly shouldn't take up 95% of CPU time.

How about optionally being able to turn SSL off, and let the user have 
the possibility to use SSH tunneling instead? That is often more 
available at the remote end (at least for me :-). Now I  do the backup 
to a local disk, and then do a rsync over ssh to the far end. Probably 
more I/O efficient, but NOT disk efficient! :-)

I looked at the code, but didn't see an obvious way to modify it.

Magnus