ZyXEL Communications PMG2006-T20A User Manual page 50

DHCP
A DHCP (Dynamic Host Configuration Protocol) server can assign your PMG2006-T20A an IP address,
subnet mask, DNS and other routing information when it's turned on.
DNS
DNS (Domain Name System) is for mapping a domain name to its corresponding IP address and vice
versa. The DNS server is extremely important because without it, you must know the IP address of a
networking device before you can access it.
RADVD (Router Advertisement Daemon)
When an IPv6 host sends a Router Solicitation (RS) request to discover the available routers, RADVD with
Router Advertisement (RA) messages in response to the request. It specifies the minimum and maximum
intervals of RA broadcasts. RA messages containing the address prefix. IPv6 hosts can be generated
with the IPv6 prefix an IPv6 address.
7.1.2.2 About UPnP
Identifying UPnP Devices
UPnP hardware is identified as an icon in the Network Connections folder (Windows XP). Each UPnP
compatible device installed on your network will appear as a separate icon. Selecting the icon of a
UPnP device will allow you to access the information and properties of that device.
NAT Traversal
UPnP NAT traversal automates the process of allowing an application to operate through NAT. UPnP
network devices can automatically configure network addressing, announce their presence in the
network to other UPnP devices and enable exchange of simple product and service descriptions. NAT
traversal allows the following:
• Dynamic port mapping
• Learning public IP addresses
• Assigning lease times to mappings
Windows Messenger is an example of an application that supports NAT traversal and UPnP.
See the Chapter 9 on page 70
Cautions with UPnP
The automated nature of NAT traversal applications in establishing their own services and opening
firewall ports may present network security issues. Network information and configuration may also be
obtained and modified by users in some network environments.
When a UPnP device joins a network, it announces its presence with a multicast message. For security
reasons, the PMG2006-T20A allows multicast messages on the LAN only.
Chapter 7 Home Networking
for more information on NAT.
PMG2006-T20A User's Guide
50