In Paragon Hard Disk Manager and derivative solutions, Backup files/disks to NAS/DAS and file backup from NAS is performed the same way as transferring data from/to network location: using TCP/IP with data conversion through NFS (Network File System) or other protocol.
It’s not possible to back up disk/partition from NAS/DAS using Hard Disk Manager. To back up disk/partition, it’s required to have direct access to the disk’s controller through supported interface (USB/PATA/SATA), to read disk’s file system and geometry data.