WAN Optimization, Web Cache, Explicit Proxy, and WCCP
You can use FortiGate WAN optimization and web caching to improve performance and security of traffic passing between locations on your wide area network (WAN) or from the Internet to your web servers. You can also use the FortiGate unit as an explicit FTP and web proxy server.
If your FortiGate unit supports web caching, you can also add web caching to any HTTP sessions including WAN optimization, explicit web proxy and other HTTP sessions.
This document describes how FortiGate WAN optimization, web caching, explicit web proxy, explicit FTP proxy and WCCP work and also describes how to configure these features.