Wi-Fi is a network technology that uses radio waves to link multiple computers. It grew out of proprietary technologies developed by Lucent, and was standardised by the IEEE under the inspiring and memorable name of 802.11.
The most common Wi-Fi standard is 802.11b, which specifies a maximum data
rate of 11 Mbps on each of 13 channels around 2.4 GHz. Due to protocol over-
head, the maximum available throughput on 802.11b is approximately 5.5
Mbps.
Wi-Fi is a data transmission system designed to provide location
independent network, access between computing devices by using radio
waves rather than cable infrastructure. It provides users, wireless access to
the services of the corporate network across a building or a campus.
The Institute of Electrical and Electronics Engineers (IEEE) has
ratified 802.11 specifications as a standard for WLANs. This version of
802.11 provides 1 Mbps and 2Mbps data transfer rates. Like all other 802
standards, 802.11 focuses on the bottom two levels of the OSI model,
physical layer and the data link layer. Network users can access LAN almost
from anywhere, without restrictions.
The IEEE standards development process can be broken down into
seven basic steps, as follows:
1) Securing Sponsorship: An IEEE-approved organization must sponsor
a standard. A sponsoring organization is in charge of coordinating and
supervising the standard development from inception to completion. The
professional societies within IEEE serve as the natural sponsor for many
standards.
2) Requesting Project Authorization: To gain authorization for
the standard a Project Authorization Request (PAR) is submitted to the
IEEE-SA Standards Board. The New Standards Committee (NesCom) of the
IEEE-SA Standards Board reviews the PAR and makes a recommendation
to the Standards Board about whether to approve the PAR.
3) Assembling a Working Group: After the PAR is approved, a
"working group" of individuals affected by, or interested in, the standard is
organized to develop the standard. IEEE-SA rules ensure that all Working
Group meetings are open and that anyone has the right to attend and
contribute to the meetings
4) Drafting the Standard: The Working Group prepares a draft of the
proposed standard. Generally, the draft follows the IEEE Standards Style
Manual that sets “guidelines” for the clauses and format of the standards
document.
5) Balloting: Once a draft of the standard is finalized in the Working
Group, the draft is submitted for Balloting approval. The IEEE Standards
Department sends an invitation-to-ballot to any individual who has
expressed an interest in the subject matter of the standard.
Anyone who responds positively to the invitation-to-ballot becomes a
member of the balloting group, as long as the individual is an IEEE member
or has paid a balloting fee. The IEEE requires that a proposed draft of the
standard receive a response rate of 75% (i.e., at least 75% of potential ballots
are returned) and that, of the responding ballots, at least 75% approve the
proposed draft of the standard. If the standard is not approved, the process
returns to the drafting of the standard step in order to modify the standard
document to gain approval of the balloting group.
6) Review Committee: After getting 75% approval, the draft standard,
along with the balloting comments, are submitted to the IEEE-SA Standards
Board Review Committee (RevCom). The RevCom reviews the proposed
draft of the standard against the IEEE-SA Standards Board Bylaws and the
stipulations set forth in the IEEE-SA Standards Board Operations Manual.
The RevCom then makes a recommendation about whether to approve the
submitted draft of the standard document.
7) Final Vote: Each member of the IEEE-SA Standards Board places a
final vote on the submitted standard document. It takes a majority vote of the
Standards Board to gain final approval of the standard. In general, if the
RevCom recommends approval, the Standards Board will vote to approve
the standard.
APPLICATIONS OF WI-FI
The freedom to roam offers numerous user benefits for a variety of
work environments, such as:
1) Immediate bedside access to patient information for doctors and hospital
staff
2) Easy, real-time network access for on-site consultants or auditors
Improved database access for roving supervisors such as production line
managers, warehouse auditors, or construction engineers
3) Simplified network configuration with minimal MIS involvement for
temporary setups such as trade shows or conference rooms
4) Faster access to customer information for service vendors and retailers,
resulting in better service and improved customer satisfaction
Location-independent access for network administrators, for easier on-site
troubleshooting and support
5) Real-time access to study group meetings and research links for students
ADVANTAGES OF WI-FI
1) Wi-Fi allows LAN to be deployed without cabling for client devices,
typically reducing the costs of network development deployment and
expansion.
2) Spaces where cables cannot be run, such as outdoor areas and
historical buildings, can host wireless LANs.
3) The price of chipsets for Wi-Fi continues to drop, making it an
economical networking option included in ever more devices.
4) Products designed as “Wi-Fi certified” by the Wi-Fi Alliance are
backwards interoperable. Wi-Fi is a global set of standards. Unlike
mobile telephones, any standard Wi-Fi devices will work anywhere in
the world.
5) New protocols for Quality of service (WMM) make Wi-Fi more
suitable for latency- sensitive applications (such as voice and video),
and power saving mechanisms (WMM Power Save) improve battery
operation.
6) Because of the comfortable and quick installation people often replace
bold wired LANs with Wi-Fi. Such connection allows moving your
machine around the place without losing the Internet or other network
resources.
7) However, building Wi-Fi network is often the cheapest way to
achieve the desired connection with the surroundings. The price of a
single wireless adapter is decreasing almost every day, so making a
large network area by means of Wi-Fi is the most reasonable way.
8) Quick, easy setup: setting up a wireless network may sound like a
daunting task, but it's actually a pretty straightforward process. Wi-Fi
networks don't require professional installation, and, best of all, there
are no holes to drill or wires to run through walls
9) Fast data transfer rates: With transfer speeds up to 54 megabits (Mb)
per second (6.75 megabytes), 802.11g is currently the fastest
commercially available Wi-Fi protocol on the market.
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