ionCube produces leading tools for PHP source code protection to secure your PHP software from prying eyes and to combat software piracy. Featuring an advanced compiled-code encoding engine that translates source to highly efficient bytecodes, ionCube encoding tools deliver the ideal combination of maximum source code protection without sacrificing performance, reliability or language compatibility.

Installing ionCube Loader:
1. Download the program and store it on your server using wget or FTP.

wget http://downloads2.ioncube.com/loader_downloads/ioncube_loaders_lin_x86.tar.gz
tar -xvf ioncube_loaders_lin_x86.tar.gz

Now lets move the iconcube directory to a permanent location
mv ioncube/ioncube_loader_lin_5.3.so /usr/lib/extensions/no-debug-non-zts-20090626/

The output should be something similar to:
#php -v
PHP 5.3.5 (litespeed) (built: Dec 8 2012 15:08:51)
Copyright (c) 1997-2004 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies
with the ionCube PHP Loader v4.2.2, Copyright (c) 2002-2012, by ionCube Ltd.

php.ini file /usr/local/lib/php.ini
zend_extension=”/usr/lib/extensions/no-debug-non-zts-20090626/ioncube_loader_lin_5.3.so”

7. Save the changes

8. Restart the web server to take effect
/etc/rc.d/init.d/httpd restart