Chapter 23 WAN Optimization, Web Cache, Explicit Proxy, and WCCP : The FortiGate explicit web proxy : Explicit web proxy configuration overview : Other explicit web proxy options
  
Other explicit web proxy options
You can change the following explicit web proxy options as required by your configuration.
HTTP port, HTTPS port, FTP port, PAC port
The TCP port that web browsers use to connect to the explicit proxy for HTTP, HTTPS, FTP and PAC services. The default port is 8080 for all services. By default HTTPS, FTP. and PAC use the same port as HTTP. You can change any of these ports as required. Users configuring their web browsers to use the explicit web proxy should add the same port numbers to their browser configurations.
Proxy FQDN
Enter the fully qualified domain name (FQDN) for the proxy server. This is the domain name to enter into browsers to access the proxy server.
Max HTTP request length
Enter the maximum length of an HTTP request in Kbytes. Larger requests will be rejected.
Max HTTP message length
Enter the maximum length of an HTTP message in Kbytes. Larger messages will be rejected.