Chapter 7 Wireless LAN

7.11.2 Additional Wireless Terms

The following table describes some wireless network terms and acronyms used in the P-2812HNU-51c’s Web Configurator.

Table 48 Additional Wireless Terms

TERM

DESCRIPTION

RTS/CTS Threshold

In a wireless network which covers a large area, wireless devices

 

are sometimes not aware of each other’s presence. This may cause

 

them to send information to the AP at the same time and result in

 

information colliding and not getting through.

 

By setting this value lower than the default value, the wireless

 

devices must sometimes get permission to send information to the

 

P-2812HNU-51c. The lower the value, the more often the devices

 

must get permission.

 

If this value is greater than the fragmentation threshold value (see

 

below), then wireless devices never have to get permission to send

 

information to the P-2812HNU-51c.

 

 

Preamble

A preamble affects the timing in your wireless network. There are

 

two preamble modes: long and short. If a device uses a different

 

preamble mode than the P-2812HNU-51c does, it cannot

 

communicate with the P-2812HNU-51c.

 

 

Authentication

The process of verifying whether a wireless device is allowed to use

 

the wireless network.

 

 

Fragmentation

A small fragmentation threshold is recommended for busy networks,

Threshold

while a larger threshold provides faster performance if the network

 

is not very busy.

 

 

7.11.3 Wireless Security Overview

The following sections introduce different types of wireless security you can set up in the wireless network.

7.11.3.1 SSID

Normally, the P-2812HNU-51c acts like a beacon and regularly broadcasts the SSID in the area. You can hide the SSID instead, in which case the P-2812HNU- 51c does not broadcast the SSID. In addition, you should change the default SSID to something that is difficult to guess.

This type of security is fairly weak, however, because there are ways for unauthorized wireless devices to get the SSID. In addition, unauthorized wireless devices can still see the information that is sent in the wireless network.

7.11.3.2 MAC Address Filter

Every device that can use a wireless network has a unique identification number, called a MAC address.1 A MAC address is usually written using twelve hexadecimal

 

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P-2812HNU-51c User’s Guide