What You Can Do In This Chapter; What You Need To Know - ZyXEL Communications USG40 User Manual

Figure 275 SMTP Redirect Example

14.1.3 What You Can Do in this Chapter

Use the Redirect Service screens (see
SMTP redirect rules.

14.1.4 What You Need to Know

Web Proxy Server
A proxy server helps client devices make indirect requests to access the Internet or outside network
resources/services. A proxy server can act as a security policy or an ALG (application layer
gateway) between the private network and the Internet or other networks. It also keeps hackers
from knowing internal IP addresses.
A client connects to a web proxy server each time he/she wants to access the Internet. The web
proxy provides caching service to allow quick access and reduce network usage. The proxy checks
its local cache for the requested web resource first. If it is not found, the proxy gets it from the
specified server and forwards the response to the client.
HTTP Redirect, Security Policy and Policy Route
With HTTP redirect, the relevant packet flow for HTTP traffic is:
Security Policy
1
Application Patrol
2
HTTP Redirect
3
Policy Route
4
Chapter 14 Redirect Service
Section 14.2 on page
ZyWALL/USG Series User's Guide
396
398) to display and edit the HTTP and