A full sector-based backup image includes all contents of a partition or a hard disk at the moment of its creation. If you roll back your system to the initial state on a regular basis, that’s exactly what you’re looking for. But if you want to have multiple backup archives of the same partition reflecting certain time stamps, unchanged data will inevitable be duplicated in all archives and take additional space on backup media. To tackle this issue there has been developed a supplementary technique called Differential Sector Backup.
A differential archive only contains data changed since the time of creating a full archive, which forms a base (or a parental image) in this case, thus considerably saving your system resources. It is realized by the exact bit-wise comparison of the previous partition’s data (saved in the parental image) with the current data (that is actually the partition itself). To restore this kind of backup you will require a full image and one of its differentials, what is very convenient.
This function is only available for single primary and logical partitions.
Incremental archive is a further way of optimizing the process of disk imaging. Unlike differentials, it may not only contain data changed since the time of creating a full sector-based archive, but one of its increments as well, thus allowing to save more time and the backup storage. The main principal here is the shorter the interval between increments, the less data is backed up. In general this type of backup is great except for one thing – when you restore an incremental archive there will be processed the initial full image and all increments between, which depending on the size of your backup chain, may take plenty of time. Anyway unlike backups, the restore operation is an emergency, which might not happen at all.
Paragon’s incremental sector-based archive employs an innovative technology that significantly improves the backup performance. Its core is in introduction of a special index file (.pfi) that keeps meta-information on the corresponding incremental image. It’s much smaller than the image itself and is used to calculate the difference between the current and previous state of a backup object. Thus, when you’re going to do an increment to a full archive of your system partition stored on the network, only its index file is processed over the net (a couple of megabytes at most), not the entire image, which minimizes both, the network traffic and backup time. Another new thing is change of a backup format – all increments are saved in .vhd (Virtual Hard Drive) containers.
Please note that the current version of the product has a number of limitations regarding sector-based increments:
A full file-based archive only contains files and folders. It is really efficient when backing up an e-mail database or particular documents, as no redundant data is processed. But if you care about maintaining a files history, you can benefit from one more supplementary technique called Incremental File Backup.
An incremental archive only contains data changed since the time of creating a full or incremental file-based archive. It is smaller and takes less time to create, but you will require the initial full image and all of its increments to restore the latest point of this kind of backup.
File Increment to a Sector Backup is a unique technology on the market so far that bridges two principally different approaches of the data backup: the file-based backup and the sector-based backup. With its help you can now create a sector-based backup of your system to get it back on track in minutes in case of a virus attack or a hardware malfunction and then just make file-based incremental images to the previously created sector-based backup to keep updated only information that is critical for you. Thus you will considerably save your system resources.
Our program supports several techniques of storing backup images. Let’s take a closer look at them all to understand what kind of storage is able to provide better security: