Explicit Web proxy topologies
You can configure a FortiGate unit to be an explicit web proxy server for Internet web browsing of IPv4 and IPv6 web traffic. To use the explicit web proxy, users must add the IP address of the FortiGate interface configured for the explicit web proxy to their web browser proxy configuration.
Explicit web proxy topology
if the FortiGate unit supports web caching, you can also add web caching to the security policy that accepts explicit web proxy sessions The FortiGate unit then caches Internet web pages on a hard disk to improve web browsing performance.
Explicit web proxy with web caching topology