Slow Backup to Disk Performance on BE 3600 Appliance.

Hi,

I am using the BE3600 Appliance to backup Physical server size 189GB on Gigabit network. The whole backup to disk process used 9 hours to complete with the throughput rate at 2376MB/min (performed Client-side Dedupication).  But It only used 50 mins with throughput 5500 MB /min to complete the backup to tape (Used LTO6 tape).

Can anyone assist me on this issue?