Does it make a difference?

Data you can encrypt using some directives and that takes place on client.  If looking for really good solution and encrypt traffic only between points like client and storage node (without encryption on backup target like tape or disk) then I would suggest to check network encryption modules (hardware).

Can you tell me more about these directives and how to implement them?

Go to NetWorker documentation and you will find explanation inside.  Bare in mind that such approach will mess up your de-dupe and compression stats on backup end plus it will take couple CPU cycles from the client.

helghareeb wrote: Does it make a difference?

Yes.  If you have task of securing both, you must encrypt network traffic between points plus data on backup storage.  If you need metadata only, then you do not worry about backup target.  Depending on requirements, you design solution. Normally, if there is real requirement for this, you rely on hardware products designed for this solely purpose.

about data

In the documentation (How to encrypt data in NetWorker?)it comes to encrypting files, and if you want to encrypt the transmission VMware\hyper-V images? This directive will work?

Thank you so much for the clarification. Truly appreciate that.

I do not think this applies to hypervisors and backup using their API.  I never had to consider such case, but I would suspect if you use hypervisor API based backups things are a bit different, but I do not have answer on that.