Overcoming Zip 2.04g limitations (4Gb/65535) for backing up big volumes of data


09-May-2008	Home \| Overcoming Zip 2.04g restrictions

Overcoming Zip 2.04g limitations (4Gb/65535) for backing up big volumes of data

The Native Zip compression implemented in D_back software is based on the InfoZip Official Freeware Zip/Unzip source code. According to the strict interpretation of the PKZIP 2.04g zip specification, the maximum size of a single zip file is 4Gb and the maximum number of files is 65535 per archive.
To overcome this restrictions for backing up big volumes of data we offer original zip slicing technology.

The main idea of this method is quite simple. All input files are grouped and packed into the separated zip files - slices. Each slice is the completed zip file, which can be unzipped independently. The maximum size of each zip slice is customized in backup profile - this is the general parameter.
The slicing algorithm tries to group and pack files into different slices in such a way, that the size of each slice (zip) file would not exceed the customized value.

It is obvious, that this cool feature gives you important benefits:

You can backup practically unlimited volumes of data in the several zip files.
Good compatibility. Each slice is a completed zip 2.04g compatible file and can be processed (unzipped) independently by a lot of zip compressors.
This is a good method for preparing data for burning to DVD or CD.