ZyXEL Communications Vantage Service Gateway VSG-1200 V2 User Manual

VSG-1200 V2 User’s Guide

Chapter 1 Getting to Know Your VSG

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The VSG allows you to maintain a subscriber database on the VSG without setting up an 
external RADIUS server. Subscriber accounting and authentication are done using the local 
subscriber database.

Accounting can be done using an external RADIUS server or the built-in accounting feature.

Once connected to the network, the VSG can redirect the subscriber to a specified web site and 
display advertising links. This can be a source of extra online advertising revenues and 
increased business exposure.

With the walled garden feature, subscribers are able to access predetermined web sites without 
logging in. The VSG blocks full Internet access until the subscribers log in.

The VSG is able to forward and retrieve e-mail messages when the subscriber’s default e-mail 
server is down or behind a firewall.

With DNS proxy, the VSG provides DNS redirection when a subscriber’s configured DNS 
server is behind a firewall or located in a private Intranet.

NAT (RFC 1631) is the translation of the IP address of a host in a packet, for example, the 
source address of an outgoing packet, used within one network to a different IP address known 
within another network. 

The VSG automatically performs NAT on the LAN. You can also set the VSG to perform 
NAT on the WAN for VPN (IPSec and PPTP) connections. 

Static routes tell the VSG how to forward IP traffic when you configure the TCP/IP 
parameters manually and disable NAT.