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10 Jun 2011 By ABradney-George

Using The 7z File Format In 7-Zip

10 Jun

A Look At How 7-Zip's Unique File Format Can Be Used For Easier File Compression, Backup And Sharing Options.

7-Zip creator Igor Pavlov has gone beyond just creating a powerful free compression tool - he has also created an archive file format to go with it. Designed for best use within 7-Zip, the 7z format provides solid file compression with a powerful and competitive compression ratio.

Set to be just as good as the popular 7-Zip utility, this archive format is already supported by other programs including WinRAR and PowerArchiver. Some of the main features of 7z format are:

Strong AES-256 encryption
Ability of using any compression, conversion or encryption method
Supporting files with sizes of up to a thousand GB and beyone
Unicode file names
Compression of archive headers

One of the standout features for 7z is the strong AES-256 encryption which uses a 256-bit cipher key for advanced password security. This features, along with the versatility of file sizes puts 7z in a position to become one of the most useful archive types available.

The 7z Compression Format

The open architecture of 7z means that it can also support new compression methods to maintain it's power and functionality. Currently the default compression method used by 7z is LZMA, which is known for it's:

High compression ratio
High compression speed of about 1 MB/s on a 2 GHz CPU
High decompression speed of about 10-20 MB/s on 2 GHz CPU
Small memory requirements for decompressing

This gives people with basic and advanced file archiving needs a range of options. More advanced users can also still choose to use or develop another compression method more suited to their needs, so 7z is flexible for all users.

The only consideration for this file format is compatibility. If file sharing is a consideration, it is important to look at what programs may not support the 7z format. In cases where there is uncertainty about compatibility, it might be safer to choose a more widely used format such as ZIP. But for personal file archiving, this format may very well be the most efficient and convenient to use.