to install it on ubuntu
$ sudo apt-get install zsync
Suppose u have the alpha version of karmic koala and kept it as karmic.iso in your home folder. For updating this image to the final release I typed the following command.
$ zsync -i karmic.iso http://releases.ubuntu.com/karmic/ubuntu-9.10-desktop-i386.iso.zsync
zsync fills a gap in the technology available for large-scale file distribution. Three key points explain why zsync provides a genuinely new technique for file distribution:
- Client-side rsync — zsync uses the rsync algorithm, but runs it on the client side, thus avoiding the high server load associated with rsync.
- Rsync over HTTP — zsync provides transfers that are nearly as efficient as rsync -z or cvsup, without the need to run a special server application. All that is needed is an HTTP/1.1-compliant web server. So it works through firewalls and on shared hosting accounts, and gives less security worries.
- Handling for compressed files — rsync is ineffective on compressed files, unless they are compressed with a patched version of gzip. zsync has special handling for gzipped files, which enables update transfers of files which are distributed in compressed form.