Zend Guard 4

Zend Guard enables the protection and mass distribution of commercial PHP applications. Zend Guard provides independent software vendors and IT managers with the ability to safely distribute and manage the deployment of their PHP applications while protecting their source code. Zend Guard is comprised of two key components, Zend Guard's encoder and Zend Guard's license manager.

Supported operating systems:
o Linux x86
o Linux x86-64
o Windows® x86 2000 / XP / 2003
o Mac OS X 10.4

Product Home Page : http://www.zend.com/products/zend_guard