Looks like you can get about 75 MB / Sec write speed over the LAN unencrypted. You'll have to determine if that speed is within the design specs of your network and disk architecture. When you encrypt, you do add some CPU cycles, but normally that added CPU would not be a limiting factor since the algorithms are very efficient - especially with modern CPUs. I can only guess your machine may have a CPU bottleneck. Can you confirm what your CPU architecture is on the computer, whether the machine is physical or virtual, and if there are any other processes using significant CPU during the backup?
After digging around a bit more, I have some additional information. The current backup process does not multi-thread backups for individual files over a LAN (cloud backups are chunked and do no exhibit this issue). So, while the Thread Count option in Settings tells the product how many file processing (backup/compression/encryption) threads to run during a backup, if you are only backing up a single file over on the local network, that file will not be backed up with multiple threads. This is going to be remedied in a future release when the new backup format is introduced. But for now, when you enable encryption on your backup, you will introduce additional CPU Cycles on that one CPU Core processing that file. On many modern processors, this will not bottleneck the backup, but it may be causing a CPU bottleneck on your system. Can you tell me about your CPU (model) and your network card speed (100Mb, 1Gb).
I would also recommend you test with compression since the compression step occurs before encryption. You may find that if you get 70% compression, that the backup completes more quickly as there is far less data to encrypt and send across the network.
Thanks David. I appreciate the help. Not sure what more I can do. The campus really wants us to move to Veeam since we have a campus license agreement in place. I am against it but we will see.
Since we can't do a purchase order, it makes things more difficult in these times of budget cutbacks.