If you travel frequently, chances are you are quite familiar
with the existence of wireless networks. Most hotels, coffee shops,
airports, and libraries offer Wi-Fi or 802.11 networks. Many cities are
beginning to offer Wi-Fi connections also, offering low-cost Internet
access to residents. Eventually wireless networks may become so prevalent
that we’ll be able to connect to the Internet from just about anywhere.
With this in mind, Windows 7 makes creating and connecting to wireless
networks very easy. With Windows 7, Microsoft has taken the time to revamp
the wireless networking interface, making it considerably easy to create
and connect to wireless networks.The beauty of wireless networking correlates directly to the word
wireless. Wireless networks allow you the freedom to
move about, whether in your home or on the road, which can make your life
considerably easier when you need to connect to a network. With wireless
networking, you gain the complete functionality of a standard network
without the need for any cables to connect the computers or devices. This
eases the requirements and restrictions of regular networks, but it adds
some complexity and additional pitfalls to the networking process.
1. Wireless Network Technologies
The most common wireless network technologies fall under
the Institute of Electrical and Electronics Engineers (IEEE)
802.11 specification. Although other wireless technologies exist, they
are not as prevalent as 802.11 (Wi-Fi) networks. Wi-Fi networks transmit
radio waves between devices to allow network communications. Wi-Fi uses
the 2.4 GHz and 5 GHz spectrums. There are three major standards within
the Wi-Fi designation. See Table 1 for a listing of
the major standards and their specifications.
Table 1. Common wireless networking technologies
| Version | Transmission
frequency | Transmission
rate |
|---|
| 802.11a | 5 GHz | Up to 54
Mbps |
| 802.11b | 2.4 GHz | Up to 11
Mbps |
| 802.11g | 2.4 GHz | Up to 54
Mbps |
| 802.11n | 2.4 GHz, 5 GHz, or
both | Up to 540
Mbps |
The 802.11b specification was the first Wi-Fi technology
introduced to the market. It uses the 2.4 GHz spectrum to transmit data
at 11 Mbps. The 802.11b specification uses Complimentary Code Keying
(CCK) coding to transmit data. While 802.11b has enjoyed the most
widespread use, the lowering costs of faster technologies are rapidly
replacing it with newer technologies.
The 802.11a specification transmits in the 5 GHz spectrum at a
transmission rate of 54 Mbps. This specification uses Orthogonal
Frequency-Division Multiplexing (OFDM) to transmit data, which is
considerably better than the CCK coding standard. Additionally, 802.11a
has more usable channels than 802.11b. This, plus the fact that the 5
GHz spectrum typically has less interference than 2.4 GHz, gives 802.11a
a considerably faster transmission rate.
The 802.11g specification transmits in the 2.4 GHz spectrum at a
transmission rate of 54 Mbps. This specification also uses OFDM to
transmit data, and it enjoys the most widespread use of the newer
technologies.
The 802.11n specification transmits in the 2.4 GHz, 5 GHz, or both
spectrums. 802.11n offers up to 540 Mbps while using
Multiple-Input-Multiple-Output (MIMO) technology. Essentially this means
that the client computer and the wireless access point will use multiple
receivers and multiple transmitters to achieve improved performance.
Although multiple data streams can help your computer achieve higher
throughput, many standard 802.11n devices combine strong, weak, and
reflected signals into one data stream to maximize the range.
These technologies fall under the Wi-Fi designation, since devices
that use the 802.11 family of standards are typically certified for
interoperability by the Wi-Fi Alliance. Windows 7 supports each of these
wireless technologies and the devices used to make connections to these
types of networks.
New networking standards are also in the marketplace today. It
bears noting that early adoption of new technologies does not always
favor the consumer, because some products in the market may support
early adoption of a standard that is not yet finalized. Therefore, if
you purchase products too early, you may have to purchase additional
hardware to support the additional features defined in the final version
of the standard. Though this is not always true, be wary of purchasing
the latest and greatest wireless products. Take some time to research
the technology before buying equipment on impulse.
Not all 802.11 specifications are about transmission speed and
rate, however. The 802.11i specification offers enhanced security. The
802.11h specification offers frequency and power control management. The
802.11e specification offers quality of service enhancements.
NOTE
The 802.1x specification is not part of the 802.11 family of
protocols. It works with wireless and wired network protocols and
provides a framework for authenticating users and controlling their
access to a protected network.
Another emerging wireless technology is Worldwide Interoperability
for Microwave Access (WiMax). WiMax is not really a technology, but a
stamp of approval for use with the 802.16 specification in broadband
wireless deployments in metropolitan areas. WiMax-certified equipment
usually uses the 2.5 GHz spectrum, but the 3.5 GHz, 2.3 GHz, and 5 GHz
spectrums are available in some regions. Currently, a movement exists to
use the 700 MHz spectrum for future WiMax deployments.
2. Wireless Network Devices
Wireless devices come in different shapes and sizes. A
wireless device is the network adapter used to make the connection to
wireless networks. A wireless network adapter is the actual hardware
device you install into a slot or port in your computer. You must have a
wireless network adapter to create a wireless network connection, which
in turn allows you to connect to a wireless network.
Most new portable computers offer integrated wireless networking
adapters. Older cards are available for older laptops that go into the
PC Card or PCMCIA slot, but these are increasingly less common to find.
PCI cards exist for the desktop and workstation. USB adapters are now
more prevalent in the market, and they will work in all computers with a
USB slot (although computers without USB 2.0 slots may experience
performance or compatibility problems).
You can find wireless network adapters at just about any store
that carries electronics. Most office supply, electronics, and retail
stores offer you the ability to purchase wireless adapters for your
computer. Make sure that you purchase the correct card for the type of
wireless technology you are using. If you are in doubt, you might want
to buy an 802.11g adapter, since it can use both 802.11g and 802.11b
technologies to communicate. Although likely more expensive, an 802.11n
adapter can use 802.11a, 802.11b, and 802.11g, as well as
802.11n.
The device to which your wireless adapter connects is a wireless
router or a wireless access point. At the office or out on the town, you
may be able to use someone else’s wireless router or wireless access
point to access the Internet. At home, however, you must purchase the
necessary wireless router or a wireless access point. Several
manufacturers produce wired/wireless router combinations. A
wired/wireless router, such as the Linksys Wireless N Broadband router,
has ports for network cables that use wired communications as well as
receivers for receiving wireless communications.
3. Installing and Configuring a Wireless Adapter
You must have a wireless adapter or chip in your computer
in order to create a wireless connection. You can see the devices
installed in your computer using Device Manager. Device Manager allows you to manage the
different devices in your system from a single console. You have the
ability to enable or disable devices, update or roll back the device
drivers, and uninstall devices.
You can open the Computer Management console to use Device Manager by
following these steps:
Click Start, right-click Computer, and then select
Manage.
In the Computer Management console, click Device Manager in
the left pane.
Your computer’s wired and wireless adapters should be listed
under the Network Adapters node. Expand this node by double-clicking
it.
If you have a
PC Card, ExpressCard, or a USB adapter, slide the card into the
appropriate slot in your computer. Once you have installed the PC Card,
ExpressCard, or USB adapter into your computer, Windows 7 should
automatically see the device and install a driver for the adapter or ask
you to install a driver for the adapter.
If you are using an integrated wireless network card in your
computer and this card is not enabled in firmware, reboot the computer
into the firmware. (Most OEM manufacturers use the Delete key, but some
use F2 or Esc. Press the Delete, F2, or Esc key every second or so after
the reboot to enter the main firmware screen.) Usually, you can find the
network card settings under Integrated Devices. Once you have found the
wireless network card settings in your firmware, select and enable the
device. After you have enabled the device, save the changes in the
firmware and reboot your computer into the operating system.
When you have completed the setup process, you will need to open
Device Manager to verify that the installation of the wireless adapter
finished correctly. In Device Manager, right-click on the adapter you
previously installed or enabled and select Properties from the context
menu. On the Driver tab, verify that the details for the Driver Provider
listing are correct. If you see Microsoft listed as the driver vendor,
you should go to your network adapter manufacturer’s website and
download the latest driver for your network card. This allows you to use
the entire functionality of the card. Microsoft drivers usually allow
you only the lowest common features of the card.
If you do not see a network adapter listed in the Device Manager
screen under Network Adapters, you should verify that the device does
not show up under Other Devices as a network controller. If this
happens, you should go to your network adapter manufacturer’s website
and download the latest driver for your network card.
