Wireless Networking
| Wireless Networking |
| Desktop Training - DSL |
Wireless Networking
Configuring a Wireless Access Connection
Configuring a wireless access point is similar regardless of the brand or version. This setup will focus on a 3 COM Office Connect Wireless 11g Cable/DSL Router.
Once you log in note the version of your wireless access point and be sure to update your firmware if an update becomes available.
The very first thing you should do once you log into your wireless access point is to create a new administrative password and get rid of the default account settings as that will just leave you open for attack.
This example demonstrates setting up DHCP as this is the option most selected. Enable the router as a DHCP Server and then decide how large of a pool of addresses you want to use. The example shows that the DHCP server will use IP Addresses from 2 to 220. If you wanted to limit connections to a handful it would limit the number of neighbors able to connect to your wireless network. Remember, your wireless network signal could carry 100 yards or more. You can also select the Auto Range to allow the system to make the decision.
One of the options you should watch on your wireless access point is how many DHCP clients are connected. In this example there are three units connected to the wireless router. Each has been assigned an IP Address by the access point. The MAC Address is listed for each of the clients connected. The IP Address may change but the MAC Address will not. The MAC Address is a unique identifier that is burned into each network interface. You should take note of these MAC Addresses as you will then know who is actually connecting to your wireless network. Also note that the access point lists these as having wired connections but in reality all were wireless connections. Also note that you can release or disconnect any wireless connections by choosing the release button.
The encryption is key to securing your network. This example shows two encryption methods, WPA and WEP. WEP is most common but WPA is actually more secure. The example shows WEP. Several settings for WEP are the encryption level, the key generation and the keys created for WEP. Choose the highest encryption levels you can as the higher the number the more secure they will be.
You must select the exact encryption level that is being used by the wireless unit that is attaching to the access point. Once you choose the encryption type you need to choose a method of creating a key, this is the encryption generation method. Manual Key Method – this method allows you to create the key manually. You will need to enter HEX code for each entry of the four keys. HEX uses letters A-F and numbers 0-9. Any combination of these characters is acceptable, but only these characters. 3COM Encryption String – this method allows you to type in a string of characters and the 3COM access point will then generate all of the HEX keys for you. ASCII - in this method you will need to type in 13 characters for each key. The access point will then generate the HE code. PASSPHRASE – this method permits you to type in a pass phrase that will then generate the HEX keys. Whatever method you choose, you will need to note two things. First, you must make note of the Active Transmit Key. This key, which can be any of the four is the key that you will need to enter into the laptop or computer if you will use encryption. The second thing is to make sure you do make the transfer to any units that you will use with encryption. This key will only work for the encryption on the access point it was setup on, not other access points. You will have to create multiple wireless setups on a laptop if you will be using different access points.
An additional security setting that you can use is the ability to limit the units that may be able to connect to your wireless access point. The setting above shows that all PCs, etc. can access this wireless router. If you choose the other option you can limit and select which PCs can connect. Below you see the MAC address of the one connection that is allowed to connect to this wireless access point.
If you have a web server, or other type of server, that you are allowing people on the Internet to access you will need to allow those connections in your wireless access router. The example below shows that all connections are blocked so that no Internet connections can be initiated by those on the Internet. In other words, there are not servers for people to access on your network.
Those services can be allowed by creating a connection which requires a static IP Address and the determination of what type of server people will connect to. The example shows a web server.
Not only can you limit the connections made from the Internet but you can also limit those computers that have access to the Internet from your internal network.
There may be times when you create a configuration for the wireless access point and you need to restart it. There is a button to do just that.
Backing up all of your settings or the access point is important for your own well being. If you have your settings saved you can always retrieve them. There is an interface for that.
Laptop, Desktop Wireless ConfigurationIntroductionWireless networks use radio waves to communicate. The first wireless network was designed and implemented by Norm Abramson a professor at the University of Hawaii in 1970. He was successful in setting up a wireless network called ALOHANET. Eventually the wireless standards were created to set up the 802.11 protocol Wi-Fi. A protocol is a language used to set a standard for communication. The 802.11 standard may function at 54 Mbps and was established by the Institute of Electrical Electronics Engineers (IEEE) in 1997. The 802.11 standard runs on the 2.4 Mhz band. The 802.11 standard requires a radio wave connection, antenna and for a Infrastructure Mode a Ethernet connection. The antennas are transducers that convert the radio frequencies to electromagnetic waves. There are two kinds of antennas. The integrated antenna is inside the card which is a the common standard. The Omni directional antenna is the other type which produces a 360 degree broadcast. ModesThere are two basic modes in the 802.11 standard. The Infrastructure mode is used to connect to an access point while the ad-hoc mode is a peer-to-peer connection between individual computers. Infrastructure Mode – connects to a wireless access point using radio waves while the wireless access point is connected to a wired network. This is a typical connection allowing a computer to access the Internet using the bandwidth of a wired network. This setup is a Basic Service Set or BBS. The Extended Service Set or ESS is a setup that allows multiple access points on the same network. The Infrastructure device acts as a master in a master slave relationship by controlling the devices that are connected to it. The access point will have a Service Set Identifier (SSID) which is broadcast on the network to allow connections to the access point. Clients use the SSID to make connections to the access point. Ad-hoc Mode - is a basic client-to-client connection that allows two clients to connect using radio waves. In order to make this connection work you must use the same SSID and both be set to ad-hoc mode. Choosing a Wireless CardThere are many confusing choices for wireless cards and it is sometimes difficult to know which ones will work with DSL. Here is a list of cards that have been reported to work with DSL. Over time probably all cards will work with DSL but it makes sense to save yourself the hassle and buy the one that works out of the box. Most Compatible With DSL Accton WN 3101J Atheros 802.11b/g (IBM OEM Mini PCI in T41,42) Avaya Wireless Silver Card 802.11b PCMCIA (Orinoco Silver) Belkin F5D7000 54G PCI Cisco Aironet 350 D-Link DWL-G650 v.C2 Lucent Orinoco Gold Netgear MA311 (all versions) Netgear MA401 (all versions) Orinoco Gold v8.72 Proxim RangeLAN-DS (with 0.83 firmware) SMC 2453
SMC2632Wv2 WaveBuddy 11WP-611AL 802.11b PC Card PenDragon USB Pendrive (128Mb) with Wireless (Prism3);also bootable AT&T Plug&Share 6700g Lucent Techologies Orinoco Silver PC24E-H-FC Dell True Mobile 1150 (Prism 2 Agere systems Use the Prism2 GUI to Configure These Cards D-Link DWL-122 USB DSE (Dick Smith Electronics) W-Lan card XH7918 Linksys WPC11 (all but v.4.0) Microsoft MN-510 USB Microsoft MN-520 (works better than with windows!) Netgear USB MA111 (v1 and v2) Cards That Work With Some Configuration Airlink+ model #WLH3010 802.11g PCI (Broadcom chipset) Belkin F5D7000 Belkin F5D7010 (Broadcom BCM94306: bcmwl5.inf - from driver CD, E-Machines, etc.) Belkin F5D6020 v2 (see this) Blitzz Net Wave Point PC 802.11b PCMCIA Edimax EW-7126 (RTL-8180 chip) Gigafast 741-UIC usb / Zydas 1201 chipset II 2216 PCMCIA Intel Pro Wireless 2100 (ndiswrapper. See this) Linksys G54 Linksys WCP11 V4.0 Linksys WPC51AB Linksys WPC54G ver 2 PCMCIA (works with ndiswrapper) Linksys WPC54G ver 3 PCMCIA (see above) Motorola WN825G (Certain drivers will freeze on modprobe. Update Driver version 1.1 works.) SMC 2635W pcmcia / ADMtek Syntax USB 400 / Prism 3 US Robotics 2210 PCI US Robotics 5416 VCTnet AirXpress PC11BR (with driver compiled from www.realtek.com) Xterasys XN-2422g Netgear WG511U Atheros chipset setup with modprobe in bootlocal.sh Zaapa wlan usb 802.11.b y 2003 driver atmel link NdiswrapperOne way to load wireless drivers is to use Ndiswrapper. Click the DSLpanel and you will see several options. The Ndiswrapper button is here, click and a small window will open for you to loacate the location of the .inf file that the Windows operating system uses. Ndiswrapper allows you to use drivers intended for Windows in a Linux environment. Often when you are setting up wireless for Linux you will have a hard time with drivers so this provides an easy way to get things up and running. One thing you will need is the Windows driver of course. When you purchase a laptop or wireless network card for a desktop you will receive the driver for that card. You will need the CD that the driver comes on so you can load it even though it is for Windows.
The default location on DSL for the inf file is: /mnt/hda1/windows/netcard.inf Of course this will not work you will have to find the inf file for your particular wireless card. You are looking for an .inf file. Here is an example: When installing DSL on a HP laptop with Centrino wirelsss, the wireless card is a Broadcom BCM94306 802.11g NIC. The inf file may be located in one of two ways. If you have a CDROM that has all of the installation files just browse to the folder for the wireless card and locate the inf file. It may have some trial and error involved as sometimes there may be several versions on the same CD. The other way to locate the inf file is if you download the Windows drivers for the wireless card. Download the program place it on a Windows machine and inflate the program so that folders are available. Now go through the folders to located the inf file. Once you have the inf file move it to a location on the hard drive. For example on the HP the inf file was named bcmwl5.inf and was moved to the /home/dsl directory. That would mean that the path you would change the small window to would be to change from: /mnt/hda1/windows/netcard.inf to /home/dsl/bcmwl5.inf Actually you could do this just to make it easier, use a wildcard: /home/dsl/*.inf The program will setup your network card and ways you go. For initial testing the ESSID should be “Any” and no encryption just to make sure you can get a connection. Verify TheConnectionYou may still need to setup a mail account or configure your web browser, but these can also indicate that the connection is working. In order to determine if you have established a basic connection you can ping the wireless access point. Become root with: sudo su Then use the ping command to check connections. ping Testing Network Connections.
Purpose of pingThis program will help determine if a computer is online by sending a ICMP ECHO_REQUEST. The expected response is in the form of ICMP ECHO_RESPONSE. In other words, there should be a return response from the machine that was contacted. Syntaxping [options] destination Example: ping 192.168.4.35 Stopping the ping CommandTurn off the pings using ctrl+c
ping is often used to establish that a network connection is actually up. ping 192.168.5.222 PING 192.168.5.222 (192.168.5.222) 56(84) bytes of data. --- 192.168.5.222 ping statistics --- You should see a return that indicates that a connection is in effect. |
