ZyXEL Communications ATP200, Руководство пользователя

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Chapter 13 Redirect Service
ZyWALL ATP Series User’s Guide
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Figure 233 SMTP Redirect Example
13.1.3 What You Can Do in this Chapter
Use the Redirect Service screens (see Section 13.2 on page 343 ) to display and edit the HTTP and SMTP
redirect rules.
13.1.4 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:
1
Security Policy
2
Application Patrol
3
HTTP Redirect
4
Policy Route