...
>So we backup 2 GB files in about 10 minutes, I think this is slow.
>My question is: why is the difference between - the elapsed processing time
>and the data transfer time - so big
>We are compressing on the client as you see!
...

Bert - You may have answered your own question.  It obviously takes
       considerable time to achieve the 64% compression you enjoyed
in that sample job, over 2 GB.  You may want to perform a comparative
test with compression turned off and/or do basic client tracing to
see where time is going in your job.  You should also get a benchmark
on your Ethernet link, using a large FTP job or other facilities,
to assure getting all the speed you expect from your datacomm link.

  Richard Sims, BU