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Wireless
Networking- 
A wireless
network is a
communication facility that uses radio as their carrier or physical
layer. The basic network consists of multiple stations communicating in
a frequency range of 2.4GHz and 4.9GHz. Wireless networking is the
state-of-art technology and an alternative to such networks, which is
hard, wired by physical copper or fiber optic cables. Such a network
has its advantages and disadvantages, compared to a wired network. The
major advantage in having a wireless network is its mobility and
elimination of cabling. Potential disadvantage is interferences due to
weather, other wireless devices, or obstructions, like walls. It is
gaining much demand in both home and business applications.
The
two-way
radio
communication works on High Frequency (HF), Very High
Frequency (VHF) and Ultra High Frequency (UHF) bands. The HF band
ranges from 3 to 30 MHz, with VHF at 30 MHz to 300MHz band, while UHF
belongs to a bandwidth of 300 MHz and 3.0 GHz.
Wireless Local Area Network (WLAN) is a wireless
connectivity limited
to local area networking. It utilizes the same functions as that of a
wired system, such as the Local Area Network (LAN). WLAN uses the
spread spectrum technology on radio waves for communication between
devices within a limited area. This facilitates the user to move around
within the broad coverage area, and still remain connected.
Mobile communication implies communication through
radio
network. The
most obvious example is establishing a wireless connectivity between a
mobile network and the mobile handset or mobile terminals. The
connection between the base stations to the core network of a mobile
phone operator, in surprisingly high numbers, is realized through radio
links. More-over, Wireless Local area Networks (WLAN) is gaining a
major growth in the market today, with radio networking in office, at
home and for public access. The base of Fixed Wireless Broadband is
formed by the combination of radio link and WLAN technologies, being a
move from proprietary into standard solutions. A further example could
be set, when realizing that the vendors have come up with a variety of
solutions, where more computers can utilize a single Internet
connection. This all have one thing in common - the computers need to
be networked.
We presently see the advent of seamless wireless data
and
voice
communication. The key capability of the next generation wireless
communication would be Voice over Internet Protocol (VoIP), which forms
a part of WLAN. The Quality-of-Service (QoS) is one of the planning
issues in VoIP over WLAN. These issues are mainly, call control,
network capacity, provisioning, architecture and others. For optimization of this
networking, the issues need to be looked into on a
WLAN-by-WLAN basis. To meet the requirements of three main market
segments is a challenge by itself in deployment parameters of WLANs.
These market segments are:
1.
Residential,
small
office and
home office applications.
2. Private networking on VoIP WLAN.
3. VoIP over WLAN interfacing the public telephone network.
Following are the benefits
of WLAN technology:
- There
are
situations where, wired connectivity between stations becomes costly,
inconvenient or impossible. For example, cable-lay becomes a very
costly proposition in a large building, where the stations are situated.
- In order to connect two buildings, separated by
some physical, legal or financial hindrance, you can either ask your
telecommunication authority to supply you with necessary links, or you
can use WLAN application for the connectivity.
- WLAN can be used as a temporary measure for
communication, which is in place for a specific time only. For example,
such a network is suitable for trade shows or a convention, where
laying cables for an Ethernet network becomes superfluous.
- In certain buildings, governed by building codes,
laying cable becomes illegal. WLAN finds a perfect application in that
situation.
- The WLAN technology is very attractive to
homeowners with several computers. A network could be set up without
drilling holes in the wall and laying the cables for connectivity.
- A mobile laptop owner can always remain connected
to the network, whether he is in the hallway, lobbies, cafeterias,
classrooms or in a meeting.
- An easy way to remain connected to the Internet at
public places. Etc
-
If you are in the middle
of a public place, like, the airport, coffee
shop, library or hotel, the chances are that you are already connected
by wireless network. Increasing number of cities are using WiFi or
802.11 networking technology to provide low cost Internet service to
the residents. A time is coming when wireless networking will enable
you to access Internet just about anywhere anytime, without the use of
wires. The mobile operators have started to provide such a wireless
Internet service, through a wireless network card, which goes in your
notebook. This renders you mobile to any place you go and even to
places in the world with a roaming account.
Security in
wireless network can be divided
into
two
parts:
Authentication and Encryption. While authentication mechanisms
can be
used to identify a client in the network and the other-way-round,
encryption makes it sure that it is not possible to intercept and
decode data being transmitted.
There are two major primary security issues
in
wireless
networking:
1. Access -
Provide adequate access grants to the selected
people who
can use the network, without which, anyone in the vicinity could gain
access into your network.
2. Privacy
- Making
sure that your network is not visible
to anyone
else. If this is not taken care of, anyone in the vicinity can watch
everything you do on the network.
The total network is secured by administrator
password,
which is
required to log into the devices, networked. The routers and access
points in the network cannot be accessed without such secured
passwords. As soon as a WLAN is set up the first thing you want to do
is to change the default password to something of your own. Without
such a password the only way to access the network is to reset the
total hardware to its factory default settings.
WLAN continuously and automatically
broadcasts the
network
name, or the
Service set Identifier (SSID). SSID is the name given to your WLAN, and
all devices in the WLAN network uses this name to communicate to each
other. This process makes setting up of wireless clients in the network
extremely easy by locating your WLAN, and on the other hand. this makes
your network to be visible to anyone operating within the range of your
transmission. Turning off the SSID broadcast would make your network
invisible to others.
To enable a secured network, disable the
option of
remote
administration. Most of WLAN routers can be remotely administered, via
Internet. This feature should only be used, if the network lets you
define a specific IP address or a range of addresses, which would be
allowed to access the network administration. It is advisable to keep
the remote administration option turned off.
It won't be right to say that
your
network is
completely
secured. It is
always possible for 'snoopers' to get into your traffic. Some wireless networks
have been built and managed with more security built into it, but, for
both LAN and WLAN, we often ask ourselves - how secured are we?
Contributing writer to level343
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