ZyXEL Communications P-2602H User Manual

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 Chapter 1 Introducing the ZyXEL Device
P-2602H(W)(L)-DxA User’s Guide
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• Back up the configuration (and make sure you know how to restore it). Restoring an 
earlier working configuration may be useful if the device becomes unstable or even 
crashes. If you forget your password, you will have to reset the ZyXEL Device to its 
factory default settings. If you backed up an earlier configuration file, you would not have 
to totally re-configure the ZyXEL Device. You could simply restore your last 
configuration.
1.4  Applications for the ZyXEL Device
Here are some example uses for which the ZyXEL Device is well suited.
1.4.1  Internet Access
Your device is the ideal high-speed Internet access solution. It supports the TCP/IP protocol, 
which the Internet uses exclusively. It is compatible with all major ADSL DSLAM (Digital 
Subscriber Line Access Multiplexer) providers.  A DSLAM is a rack of ADSL line cards with 
data multiplexed into a backbone network interface/connection (for example, T1, OC3, DS3, 
ATM or Frame Relay). Think of it as the equivalent of a modem rack for ADSL. In addition, 
your device allows wireless clients access to your network resources and the Internet. A 
typical Internet access application is shown below.
Figure 1   Internet Access Application
1.4.1.1  Internet Single User Account
For a SOHO (Small Office/Home Office) environment, your device offers the Single User 
Account (SUA) feature that allows multiple users on the LAN (Local Area Network) to access 
the Internet concurrently for the cost of a single IP address
1.4.2  Making Calls via Internet Telephony Service Provider
In a home or small office environment, you can use your device to make and receive VoIP 
telephone calls through an Internet Telephony Service Provider (ITSP). 
The following figure shows a basic example of how you would make a VoIP call through an 
ITSP. You use your analog phone (A in the figure) and your device (B) changes the call into 
VoIP. Your device then sends your call to the Internet and the ITSP’s SIP server (C). The 
VoIP call server forwards calls to PSTN phones (E) through a trunking gateway (D) to the 
PSTN network. The VoIP call server forwards calls to IP phones (F) through the Internet.