CacheGuard Appliance is an all-in-one OS appliance providing firewall, antivirus, caching, compression, bandwidth allocation, load balancing, reverse and forward proxy, high availability, Web application firewall, URL guarding, and more. It can be purchased as an OS to install on your server, as an OS to run in a virtual machine, or as a hardware appliance.
LibHTP is a security-aware parser for the HTTP protocol and the related bits and pieces. That can mean many things, but the only scenario in which LibHTP has been tested so far is the one when you need to parse a duplex HTTP stream that you have obtained by passively intercepting HTTP traffic. Just feed the raw TCP stream to LibHTP and it will do the rest.