ZyXEL Communications LTE5121, User Manual

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Chapter 6 Home Networking
LTE-5121 User’s Guide
72
Subnet Mask
The subnet mask specifies the network number portion of an IP address. Your LTE Device will
compute the subnet mask automatically based on the IP address that you entered. You don't need
to change the subnet mask computed by the LTE Device unless you are instructed to do otherwise.
DHCP
DHCP (Dynamic Host Configuration Protocol) allows clients to obtain TCP/IP configuration at start-
up from a server. This LTE Device has a built-in DHCP server capability that assigns IP addresses
and DNS servers to systems that support DHCP client capability.
DNS
DNS (Domain Name System) maps 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
computer before you can access it. The DNS server addresses you enter when you set up DHCP are
passed to the client machines along with the assigned IP address and subnet mask.
6.1.2.2 About UPnP
How do I know if I'm using UPnP?
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.
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 LTE Device allows multicast messages on the LAN only.
All UPnP-enabled devices may communicate freely with each other without additional configuration.
Disable UPnP if this is not your intention.
UPnP and ZyXEL
ZyXEL has achieved UPnP certification from the Universal Plug and Play Forum UPnP™
Implementers Corp. (UIC). ZyXEL's UPnP implementation supports Internet Gateway Device (IGD)
1.0.
See Section 6.9 on page 86 for examples of installing and using UPnP.