Open BAK File

Backup Compression and Encryption

Compression is an important method to cut backup solution costs. Compressed data takes much less space and as a result more data could be stored on the same hardware. Many vendors deliver compression as part of their hardware and software backup products.

The main problem that every backup vendor needs to solve is to achieve optimal compression to performance ratio. Compression algorithms require forward data analysis to achieve optimal compression but analyzing significant amount of data may take quite a lot of processing power. And on large amounts of data this could seriously affect speed of the backup process. That is why frequently tape backup vendors implement compression inside a hardware to make it as performant as possible. Also, they limit forward data analysis to a certain amount to achieve performance and compression ration optimal for different types of data. It is worth to notice that not every type of information could be compressed efficiently. Already compressed images and videos won’t be compressed by backup hardware and software algorithms but text and structured information could be significantly compressed.

Since backup compression is typically tuned for a broad range of data it may be more efficient to use software compression specifically tuned to certain kind of files. For example, structured and text data could be very efficiently compressed by RAR, 7Z or ZIP archivers. Images may be stored in JPG or HEIC formats. Video could be compressed using MPEG-4 or HEVC compression algorithms.

It may be wise in certain cases to encrypt sensitive backup data. Many tape drive vendors provide hardware AES 256-bit encryption which ensures secure data storage. Encryption may not be advisable in every case though since it ads certain computational overhead and performance degradation. It is also important to check if hardware that you plan to use supports encryption and compression simultaneously. If encryption is performed first by hardware, then compression won’t be effective. But it will work great the opposite way.