The main purpose of this software is to encrypt and obfuscate your PHP scripts to prevent other people from accessing your source code, whether you've got a nosey host, you need extra security when selling code, or you're just plain selfish :-)
This software could allow a PHP contractor to add a whole new pricing scheme to their projects. For example: 50% of the agreed upon price will deliver a fully functional "demo" that renders itself useless after 7 days. A non-demo version will be delivered upon receipt of the other 50% and for an additional fee, full source (unencrypted) access.
No additional extensions need to be bundled into PHP to run encrypted files, and they'll run on any setup (except Apache 2) according to the site & help files. All you need for an encrypted file to run is a version of PHP >= 4, and the appropriate ixed file - the latest of which are available at the SourceGuardian website. Just bundle them with your distributions.
How secure is it? Well, practically the only way to reverse-engineer the code would require a partial rewrite and compilation of the core PHP engine, and very dedicated cracker. It's secure.
I've only used this software for a very short period of time and I have already found it to be very inspiring, it makes me anticipate future projects. I'm 100% for open-source technology, but unfortunately people will take advantage of you if you're not careful; SourceGuardian is the perfect solution. Having researched similar software by other companies, I'd have to say SourceGuardian is by far the most reasonable product for my needs.
Bundled with features such as IP restriction and timeout settings (which are a must in my opinion), this software is currently the cheapest on the market.
Easy & self-explanitory to use.
Can be run in command line mode (for super geeks).
Although it warns about making backups, because the files you encode are overwritten through a one-way (irreversable) encryption, there doesn't appear to be a backup option even though it hints that there is one available (somewhere?).
It doesn't appear you can edit or make last second changes to scripts directly through the software interface, at least in windows.
Check out the SourceGuardian website for more details and visual examples.
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