Wireless Networking 102

Troubleshooting WLAN

Start

> Connect To

> Show all Connections

Disable - Enable - Check

Disable Local Area ConnectionEnable Wireless Network

Connection

Check WLAN (Radio) LED

status on the Front Panel Dashboard.

If LED is not Glowing Check Radio Issues.

Radio Issues

Select 'Wireless Network Connection' Properties (right-click)

Click Configure button to get 'Intel PRO / Wireless LAN ..... adapter' properties

Radio Issues (Contd..)

• Select Advanced Tab

• Remove the Tick mark for 'Wireless Device Off'

• Press OK

• Check your Front Panel Dashboard WLAN LED status. It should glow for the Laptop to Transmit / Receive data.

Connecting to a Hotspot (Cont’d)

•On older equipment, you have to find the SSID of the access point (usually a short word of 10 characters or less) as well as the channel number (an integer between 1 and 11) and type these two pieces of information in manually.

Networking Components Needed for WLAN

• Client for Microsoft Networks

• File and Printer Sharing for Microsoft Networks

• QoS Packet Scheduler• AEGIS Protocol (IEEE

802.1x) v 2.2.1.0• WLAN Transport• Internet Protocol

(TCP/IP)

De-select all others

Available / Preferred Networks

Select 'Wireless Networks' Tab

Select 'Use Windows to configure my wireless network settings' Check-box

Refresh to see the available networks. Wait for 1-2 minutes & Refresh again

Select 'Advanced' button

WiFi Security

•WiFi hotspots can be open or secure.

•If a hotspot is open, then anyone with a WiFi card can access the hotspot.

•If it is secure, then the user needs to know a WEP key to connect.

•WEP stands for Wired Equivalent Privacy

WiFi Security (Cont’d)

•WEP is an encryption system for the data that 802.11 sends through the air.

•

•Encryption systems prevent non-authorized parties from accessing data.

•

•Specifically, it is the process of encoding a bit stream in such a way that only the person (or computer) with the WEP key (a digital sequence) can decode it.

WEP

•WEP has two variations: 64-bit encryption and 128-bit encryption.

•40-bit encryption was the original standard but was found to be easily broken.

•128-bit encryption is more secure and is what most people use if they enable WEP.

•For a casual user, any hotspot that is using WEP is inaccessible unless you know the WEP key.

WEP (Cont’d)

•If you are setting up an access point in your home, you may want to use a 128-bit WEP key to prevent anyone from casually eavesdropping onto your network.

•Whether at home or on the road, you need to know the WEP key, and then enter it into the WiFi's software, to gain access to the network.

Setting up a Hotspot at Home•If you already have several computers hooked together on an Ethernet network and want to add a wireless hotspot to the mix, you can purchase a Wireless Access Point and plug it into the Ethernet network.

Wireless Access Point

Setup #1

Alternate Setup using a Wireless Router

•If you are setting up a network in your home for the first time, or if you are upgrading, you can buy a Wireless Access Point Router.

•This is a single box that contains: ▫1) a port to connect to your cable modem or DSL modem,

▫2) a router, ▫3) an Ethernet hub, ▫4) a firewall and ▫5) a wireless access point.

Alternate Setup using a Wireless Router

•You can connect the computers in your home to this box either with traditional Ethernet cables or with wireless cards.

Alternate Setup (Cont’d)

WiFi Range

•Regardless of which setup you use, once you turn your Wireless Access Point on, you will have a WiFi hotspot in your house.

•In a typical home, this hotspot will provide coverage for about 100 feet (30.5 meters) in all directions, although walls and floors do cut down on the range.

WiFi Range

•Even so, you should get good coverage throughout a typical home. For a large home, you can buy inexpensive signal boosters to increase the range of the Hotspot.

One Type of AmplifierOr a directionalantenna can beused to givebetter range in a particulardirection.

Another Way to Amplify WiFi Signals

A WiFi repeateris installed to extend coverage.

WirelessAccess Point

Configuring a Hotspot•Most wireless access points come with default values built-in.

•Once you plug them in, they start working with these default values.

•However, you may want to change these for security reasons.

•You normally get to set three things on your access point.

Things to Configure in a Hotspot•The SSID -- Service Set IDentifier is a sequence of characters that uniquely names a WLAN.▫It will normally default to the manufacturer's name (e.g. "Linksys" or "Netgear").

▫You can set it to any word or phrase you like.

Things to Configure in a Hotspot•The channel – the radio link used by access point/router to communicate to wireless devices.▫Normally it will default to channel 6. ▫However, if a nearby neighbor is also using an access point and it is set to channel 6, there can be interference. Choose any other channel between 1 and 11.

Things to Configure (Cont’d)•The WEP key -- Default is disabled .

▫If you want to turn it on, you have to enter a WEP key and turn on 128-bit encryption.

▫WEP can be in text format.

Access points come with simple instructions for changing these three values. Normally you do it with a Web browser. Once it is configured properly, you can use your new hotspot to access the Internet from anywhere in your home.

Infrastructure versus Ad Hoc•All the connections we have covered today require a connection from a device equipped with a wireless network interface card (NIC) to a wireless access point.

•Generally, all such connections are operating in what is known as the “infrastructure” mode. All wireless communication must be fed into a wired network somewhere.

Infrastructure versus Ad Hoc

•Wireless devices can also communicate directly with each other, i.e., it is not required that they communicate with an access point first. This is called Ad Hoc communication.

Infrastructure versus Ad Hoc

•When devices with NIC cards communicate directly with each other, the wireless network operates in ad hoc mode.

•Essentially peer-to-peer communication is enabled.

Ad Hoc Mode•Ad Hoc connections can be used to share information directly between devices. This mode is also useful for establishing a network where wireless infrastructure does not exist.

Ad Hoc Mode•Some possible uses include:

▫Synchronize data between devices.▫Retrieve multimedia files from one device and “play” them on another device.

▫Print from a computer to a printer without wires.

•There are many applications of ad hoc networking in military and other specialized networks.