BizGuardian is based on the FreeBSD UNIX kernel. We have hardened this and spent thousands of development hours on the GUI, administration, installation and reporting tools to make it a simple product to install, configure and administer for the bulk of PC network users. As the kernel is open source we are not charging for R&D on this component of BizGuardian. Other solutions are either more expensive in R&D because they are based on proprietary Operating Systems such as Win NT, or they are often based on free operating systems such as Linux, but choose not to reflect this in their pricing structure.