User's Manual

LinkTek WL11N Wireless Broadband Router User Guide

broadcast range. Often a wireless access point such as the AP embedded in the LinkTek

WL11N, will also provide a connection to a wired network - usually Ethernet - and ultimately an

Internet connection. The IEEE 802.11 standard precisely defines the encoding techniques used

to digitally used for data transmission. The embedded wireless access point can be used by

IEEE 802.11g, 802.11b and 802.11n devices. These standards are compatible but use different

algorithms for data transmission.

802.11g uses a method called Orthogonal Frequency Division Multiplexing (OFDM) for

transmitting data at higher data rates. OFDM is a more efficient encoding method than Direct

Sequence Spread Spectrum (DSSS) transmission, the method used by 802.11b devices.

However, in order to support different data transmission rates while also be compatible with

802.11b, 802.11g uses a combination of OFDM and DSSS when 802.11b devices are present.

Range

An access point will send and receive signals within a limited range. Also, be aware that the

radio signals are emitted in all directions giving the access point a spherical operating range.

The physical environment in which the AP is operating can have a huge impact on its

effectiveness. If you experience low signal strength or slow throughput, consider positioning the

router in a different location. See the discussion below concerning the wireless environment and

location of the AP (LinkTek WL11N).

SSID and Channel

Wireless networks use an SSID (Service Set Identifier) as means of identifying a group of

wireless devices, similar to a domain or subnet. This allows wireless devices to roam from one

AP to another and remain connected. Wireless devices that wish to communicate with each

other must use the same SSID. Several access points can be set up using the same SSID so

that wireless stations can move from one location to another without losing connection to the

wireless network.

The embedded wireless access point of the router operates in Infrastructure mode. It controls

network access on the wireless interface in its broadcast area. It will allow access to the wireless

network to devices using the correct SSID after a negotiation process takes place. By default,

the LinkTek WL11N broadcasts its SSID so that any wireless station in range can learn the SSID

and ask permission to associate with it. Many wireless adapters are able to survey or scan the

wireless environment for access points. An access point in Infrastructure mode allows wireless

devices to survey that network and select an access point with which to associate. You may

disable SSID broadcasting in the web manager’s wireless menu.

In addition, the AP can use different channels (frequency bands) to avoid unwanted overlap or

interfere between control zones of separate APs. Wireless nodes must use the same SSID and

the same channel as the AP with which it wishes to associate. However, because of the nature

of the CSMA/CA (carrier sense multiple access with collision avoidance) protocol, using the

same channel on two different APs can contribute significantly to wireless congestion. If you are

using multiple APs on your network and are experiencing low throughput or significant

transmission delay, carefully consider how channels are assigned to the different APs.

Wireless Security

Various security options are available on the LinkTek WL11N including open or WEP and WPA

(including WPA-PSK). Authentication may use an open system or a shared key. Read below for

more information on configuring security for the wireless interface.