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Multicast

IP packets are transmitted in either one of two ways - Unicast (1 sender - 1 recipient) or Broadcast

(1 sender - everybody on the network). Multicast delivers IP packets to a group of hosts on the

network - not everybody and not just 1.

Internet Group Multicast Protocol (IGMP) is a network-layer protocol used to establish membership

in a Multicast group - it is not used to carry user data. IGMP version 2 (RFC 2236) is an

improvement over version 1 (RFC 1112) but IGMP version 1 is still in wide use. If you would like to

read more detailed information about interoperability between IGMP version 2 and version 1, please

see sections 4 and 5 of RFC 2236. The class D IP address is used to identify host groups and can be

in the range 224.0.0.0 to 239.255.255.255. The address 224.0.0.0 is not assigned to any group

and is used by IP multicast computers. The address 224.0.0.1 is used for query messages and is

assigned to the permanent group of all IP hosts (including gateways). All hosts must join the

224.0.0.1 group in order to participate in IGMP. The address 224.0.0.2 is assigned to the multicast

routers group.

At start up, the Device queries all directly connected networks to gather group membership. After

that, the Device periodically updates this information.

DNS Server Address Assignment

Use Domain Name System (DNS) to map a domain name to its corresponding IP address and vice

versa, for instance, the IP address of www.zyxel.com is 204.217.0.2. The DNS server is extremely

important because without it, you must know the IP address of a computer before you can access

it.

The Device can get the DNS server addresses in the following ways.

1

The ISP tells you the DNS server addresses, usually in the form of an information sheet, when you

sign up. If your ISP gives you DNS server addresses, manually enter them in the DNS server fields.

2

If your ISP dynamically assigns the DNS server IP addresses (along with the Device’s WAN IP

address), set the DNS server fields to get the DNS server address from the ISP.

IPv6 Addressing

The 128-bit IPv6 address is written as eight 16-bit hexadecimal blocks separated by colons (:). This

is an example IPv6 address

2001:0db8:1a2b:0015:0000:0000:1a2f:0000

.

IPv6 addresses can be abbreviated in two ways:

•

Leading zeros in a block can be omitted. So

2001:0db8:1a2b:0015:0000:0000:1a2f:0000

can

be written as

2001:db8:1a2b:15:0:0:1a2f:0

.

•

Any number of consecutive blocks of zeros can be replaced by a double colon. A double colon can

only appear once in an IPv6 address. So

2001:0db8:0000:0000:1a2f:0000:0000:0015

can be

written as

2001:0db8::1a2f:0000:0000:0015

,

2001:0db8:0000:0000:1a2f::0015

,

2001:db8::1a2f:0:0:15

or

2001:db8:0:0:1a2f::15

.

IPv6 Prefix and Prefix Length

Similar to an IPv4 subnet mask, IPv6 uses an address prefix to represent the network address. An

IPv6 prefix length specifies how many most significant bits (start from the left) in the address

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compose the network address. The prefix length is written as “/x” where x is a number. For

example,

2001:db8:1a2b:15::1a2f:0/32

means that the first 32 bits (

2001:db8

) is the subnet prefix.

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C

HAPTER

5

Wireless

5.1

Overview

This chapter describes the Device’s

Network Setting > Wireless

screens. Use these screens to

set up your Device’s wireless connection.

5.1.1

What You Can Do in this Chapter

This section describes the Device’s

Wireless

screens. Use these screens to set up your Device’s

wireless connection.

•

Use the

General

screen to enable the Wireless LAN, enter the SSID and select the wireless

security mode (

Section 5.2 on page 70

).

•

Use the

More AP

screen to set up multiple wireless networks on your Device (

Section 5.3 on

page 77

).

•

Use the

MAC Authentication

screen to allow or deny wireless clients based on their MAC

addresses from connecting to the Device (

Section 5.4 on page 81

).

•

Use the

WPS

screen to enable or disable WPS, view or generate a security PIN (Personal

Identification Number) (

Section 5.5 on page 82

).

•

Use the

WMM

screen

to enable Wi-Fi MultiMedia (WMM) to ensure quality of service in wireless

networks for multimedia applications (

Section 5.6 on page 83

).

•

Use the

WDS

screen to set up a Wireless Distribution System, in which the Device acts as a

bridge with other ZyXEL access points (

Section 5.7 on page 84

).

•

Use the

Others

screen to configure wireless advanced features, such as the RTS/CTS Threshold

(

Section 5.8 on page 86

).

•

Use the

Channel Status

screen to scan wireless LAN channel noises and view the results

(

Section 5.9 on page 89

).

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5.1.2

What You Need to Know

Wireless Basics

“Wireless” is essentially radio communication. In the same way that walkie-talkie radios send and

receive information over the airwaves, wireless networking devices exchange information with one

another. A wireless networking device is just like a radio that lets your computer exchange

information with radios attached to other computers. Like walkie-talkies, most wireless networking

devices operate at radio frequency bands that are open to the public and do not require a license to

use. However, wireless networking is different from that of most traditional radio communications in

that there a number of wireless networking standards available with different methods of data

encryption.

Finding Out More

See

Section 5.10 on page 89

for advanced technical information on wireless networks.

5.2

The General Screen

Use this screen to enable the Wireless LAN, enter the SSID and select the wireless security mode.

Note: If you are configuring the Device from a computer connected to the wireless LAN

and you change the Device’s SSID, channel or security settings, you will lose your

wireless connection when you press

Apply

to confirm. You must then change the

wireless settings of your computer to match the Device’s new settings.