Security; Chapter 15 Security; Overview; What You Need To Know - ZyXEL Communications P-794H User Manual

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H A P T E R

15.1 Overview

This chapter shows you how to enable and configure the P-794H's security
settings such as firewall, NAT, and firewall policies.

15.1.1 What You Need to Know

DMZ
Demilitarized Zone (DMZ) allows one IP address to be exposed to the Internet.
This is useful for special-purpose services such as Internet gaming or video
conferencing. However, as any user on the Internet can access in/out data from
the DMZ host, care should be taken when using this feature to minimize security
issues.
Port Filter
A port filtering set is a list of inside (behind NAT on the LAN) servers, for example,
web or FTP, that you can make visible to the outside world even though NAT
makes your whole inside network appear as a single computer to the outside
world.
Tigger Port
Some services use a dedicated range of ports on the client side and a dedicated
range of ports on the server side. With regular port forwarding you set a
forwarding port in NAT to forward a service (coming in from the server on the
WAN) to the IP address of a computer on the client side (LAN). The problem is
that port forwarding only forwards a service to a single LAN IP address. In order to
use the same service on a different LAN computer, you have to manually replace
the LAN computer's IP address in the forwarding port with another LAN
computer's IP address.
Trigger port forwarding solves this problem by allowing computers on the LAN to
dynamically take turns using the service. The P-794H records the IP address of a
LAN computer that sends traffic to the WAN to request a service with a specific
P-794H User's Guide
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Security

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