ZyXEL ZyWALL ATP100 User Guide - Page 378

Chapter 13 Redirect Service Even if you set a policy route to the same incoming interface and service as a HTTP redirect rule, the Zyxel Device checks the HTTP redirect rules first and forwards HTTP traffic to a proxy server if matched. You need to make sure there is no security policy blocking the HTTP requests from the client to the proxy server. You also need to manually configure a policy route to forward the HTTP traffic from the proxy server to the Internet. To make the example in Figure 261 on page 376 work, make sure you have the following settings. For HTTP traffic between lan1 and dmz: • a from LAN1 to DMZ security policy (default) to allow HTTP requests from lan1 to dmz. Responses to this request are allowed automatically. • a application patrol rule to allow HTTP traffic between lan1 and dmz. • a HTTP redirect rule to forward HTTP traffic from lan1 to proxy server A. For HTTP traffic between dmz and wan1: • a from DMZ to WAN security policy (default) to allow HTTP requests from dmz to wan1. Responses to these requests are allowed automatically. • a application patrol rule to allow HTTP traffic between dmz and wan1. • a policy route to forward HTTP traffic from proxy server A to the Internet. SMTP Simple Mail Transfer Protocol (SMTP) is the Internet's message transport standard. It controls the sending of email messages between servers. Email clients (also called email applications) then use mail server protocols such as POP (Post Office Protocol) or IMAP (Internet Message Access Protocol) to retrieve email. Email clients also generally use SMTP to send messages to a mail server. The older POP2 requires SMTP for sending messages while the newer POP3 can be used with or without it. This is why many email applications require you to specify both the SMTP server and the POP or IMAP server (even though they may actually be the same server). SMTP Redirect, Firewall and Policy Route With SMTP redirect, the relevant packet flow for SMTP traffic is: 1 Firewall 2 SMTP Redirect 3 Policy Route Even if you set a policy route to the same incoming interface and service as a SMTP redirect rule, the Zyxel Device checks the SMTP redirect rules first and forwards SMTP traffic to a SMTP server if matched. You need to make sure there is no firewall rule(s) blocking the SMTP traffic from the client to the SMTP server. You also need to manually configure a policy route to forward the SMTP traffic from the SMTP server to the Internet. To make the example in Figure 262 on page 377 work, make sure you have the following settings. ZyWALL ATP Series User's Guide 378