- Wireless Networking
Wireless
networking is the new face of networking. Wireless networking have been
around for many years. Cell phones are also a type of wireless communication
and are popular today for people talking to each other worldwide.
Wireless networking are not only less expensive than more traditional wired networking but also much easier to install. An important goal of this site is to provide you adequate knowledge for installing a wireless network and get certified in wireless networks as well as.
Wireless networking are not only less expensive than more traditional wired networking but also much easier to install. An important goal of this site is to provide you adequate knowledge for installing a wireless network and get certified in wireless networks as well as.
Perhaps you
already useing wireless networking in your local coffee shop, at the airport, or
in hotel lobbies, and you want to set up a small office or home network. You
already know how great wireless networking is, so you want to enjoy the
benefits where you live and work. It is truly transformational to one's
lifestyle to decouple computing from the wires! If you are looking to set up a
wireless network, you've come to the right place. We will show you the best way
to set up wirless network easily. Many people are looking to find out how to
use wireless networking at home.
In this
wireless networking section we provides An Absolute Beginner's Guide in the
perfect format for easily learning what you need to know to get up to speed
with wireless network without wasting a lot of time.
The organization of this site, and the special elements that we have described in this section will help you get the information you need quickly, accurately, and with clarity. In this section you will find inspiration as well as practical information. we believe that Wireless networks is a modest technology that has the power to have a huge and positive impact. This is wonderful material, and it's lots of fun! So what are you waiting for? It's time to Go for wireless networking.
The organization of this site, and the special elements that we have described in this section will help you get the information you need quickly, accurately, and with clarity. In this section you will find inspiration as well as practical information. we believe that Wireless networks is a modest technology that has the power to have a huge and positive impact. This is wonderful material, and it's lots of fun! So what are you waiting for? It's time to Go for wireless networking.
Wireless Basic
Radio Frequency Transmission Factors
Radio
frequencies (RF) are generated by antennas that propagate the waves into the
air.
Antennas fall under two different categories:
Antennas fall under two different categories:
directional
and omni-directional.
Directional
antennas are commonly used in point-to-point configurations (connecting two
distant buildings), and sometimes point-to-multipoint (connecting two WLANs).
An example of a directional antenna is a Yagi antenna: this antenna allows you to adjust the direction and focus of the signal to intensify your range/reach.
An example of a directional antenna is a Yagi antenna: this antenna allows you to adjust the direction and focus of the signal to intensify your range/reach.
Omni-directional
antennas are used in point-to-multipoint configurations, where they distribute
the wireless signal to other computers or devices in your WLAN. An access point
would use an omni-directional antenna. These antennas can also be used for
point-to-point connections, but they lack the distance that directional
antennas supply
Three main factors influence signal distortion:
- Absorption Objects
that absorb the RF waves, such as walls, ceilings, and floors - Scattering Objects
that disperse the RF waves, such as rough plaster on a wall, carpet on the floor, or drop-down ceiling tiles - Reflection Objects
that reflect the RF waves, such as metal and glass
Responsible body
The
International Telecommunication Union-Radio Communication Sector (ITU-R) is
responsible for managing the radio frequency (RF) spectrum and satellite orbits
for wireless communications: its main purpose is to provide for cooperation and
coexistence of standards and implementations across country boundaries.
Two
standards bodies are primarily responsible for implementing WLANs:
- IEEE
defines the mechanical process of how WLANs are implemented in the 802.11 standards so that vendors can create compatible products. - The Wi-Fi Alliance
basically certifies companies by ensuring that their products follow the 802.11 standards, thus allowing customers to buy WLAN products from different vendors without having to be concerned about any compatibility issues.
Frequencies bands:
WLANs use
three unlicensed bands:
- 900 MHz Used by older cordless
phones
- 2.4 GHz Used by newer cordless
phones, WLANs, Bluetooth, microwaves, and other devices
- 5 GHz Used by the newest models
of cordless phones and WLAN devices
- 900 MHz and 2.4 GHz frequencies
are referred to as the Industrial, Scientific, and Medical (ISM) bands.
- 5 GHz frequency the Unlicensed
National Information Infrastructure (UNII) band.
- Unlicensed bands are still
regulated by governments, which might define restrictions in their usage.
A hertz (Hz)
is a unit of frequency that measures the change in a state or cycle in a wave
(sound or radio) or alternating current (electricity) during 1 second.
Transmission Method
Direct
Sequence Spread Spectrum (DSSS)
uses one channel to send data across all frequencies within that channel. Complementary Code Keying (CCK) is a method for encoding transmissions for higher data rates, such as 5.5 and 11 Mbps, but it still allows backward compatibility with the original 802.11 standard, which supports only 1 and 2 Mbps speeds. 802.11b and 802.11g support this transmission method.
uses one channel to send data across all frequencies within that channel. Complementary Code Keying (CCK) is a method for encoding transmissions for higher data rates, such as 5.5 and 11 Mbps, but it still allows backward compatibility with the original 802.11 standard, which supports only 1 and 2 Mbps speeds. 802.11b and 802.11g support this transmission method.
OFDM
(Orthogonal Frequency Division Multiplexing)
increases data rates by using a spread spectrum: modulation. 802.11a and 802.11g support this transmission method.
increases data rates by using a spread spectrum: modulation. 802.11a and 802.11g support this transmission method.
MIMO
(Multiple Input Multiple Output)
transmission, which uses DSSS and/or OFDM by spreading its signal across 14 overlapping channels at 5 MHz intervals. 802.11n uses it. Use of 802.11n requires multiple antennas.
transmission, which uses DSSS and/or OFDM by spreading its signal across 14 overlapping channels at 5 MHz intervals. 802.11n uses it. Use of 802.11n requires multiple antennas.
WLAN
Standards
Standards
|
802.11a
|
802.11b
|
802.11g
|
802.11n
|
Data Rate
|
54 Mbps
|
11 Mbps
|
54 Mbps
|
248 Mbps (with 2×2 antennas)
|
Throughput
|
23 Mbps
|
4.3 Mbps
|
19 Mbps
|
74 Mbps
|
Frequency
|
5 GHz
|
2.4 GHz
|
2.4 GHz
|
2.4 and/or 5 GHz
|
Compatibility
|
None
|
With 802.11g and the original
802.11
|
With 802.11b
|
802.11a, b, and g
|
Range (meters)
|
35–120
|
38–140
|
38–140
|
70–250
|
Number of Channels
|
3
|
Up to 23
|
3
|
14
|
Transmission
|
OFDM
|
DSSS
|
DSSS/OFDM
|
MIMO
|
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