17

HTTP Redirect

This chapter shows you how to configure HTTP redirection on your ZyWALL. See Section

5.4.19on page 121 for related information on these screens.

17.1HTTP Redirect Overview

HTTP redirect forwards the client’s HTTP request (except HTTP traffic destined for the ZyWALL) to a web proxy server.

17.1.1 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 firewall 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.

17.2 HTTP Redirect, Firewall and Policy Route

With HTTP redirect, the relevant packet flow for HTTP traffic is:

1Firewall

2Application Patrol

3HTTP Redirect

4Policy Route

Even if you set a policy route to the same incoming interface and service as a HTTP redirect rule, the ZyWALL checks the HTTP redirect rules first and forwards HTTP traffic to a proxy server if matched. You need to make sure there is no firewall rule(s) 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.

 

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