Which multiple access technique is used by ieee 802.11 stands for wireless lan?
Answers
Answer:
ABSTRACT: Network technologies are
traditionally based on wireline solutions. But
the introduction of the IEEE 802.11 standards
have made a huge impact on the market such
that laptops, PCs, printers, cellphones, and
VoIP phones, MP3 players in our homes, in
offices and even in public areas have
incorporated the wireless LAN technology.
Wireless broadband technologies nowadays
provide unlimited broadband access to users
which were previously offered only to wireline
users. In this paper, we review and summarize
one of the emerging wireless broadband
technology i.e. IEEE 802.11,which is a set of
physical layer standard for implementing
wireless local area network computer
communication in the 2.4,3.6,5 and 60GHz
frequency band. They fix technology issues or
add functionality which is expected to be
required by future applications. Though some
of the earlier versions of these technologies are
obsolete (such as HiperLAN) now but still we
have included them in this review for the sake
of completeness.
Keywords: Wireless Communications, IEEE
802.11, HiperLAN, WLAN, Wi-fi.
1. Introduction
The wireless broadband technologies were
developed with the aim of providing services
comparable to those provided to the wireline
networks. Cellular networks now provide support
for high bandwidth data transfer for numerous
mobile users simultaneously. In addition to this,
they also provide mobility support for voice
communication. Wireless data networks can be
divided into several types depending on their area
of coverage. They are:
WLAN: Wireless Local Area network, in area with
a cell radius up to hundred meters, mainly in home
and office environments.
WMAN: Wireless Metropolitan Area Network;
generally cover wider areas as large as entire cities.
WWAN: Wireless Wide Area Network with a cell
radius about 50 km, cover areas larger than a city.
However out of all of these standards, WLAN
and recent developments in WLAN technology
would be our main area of study in this paper. The
IEEE 802.11 is the most widely deployed WLAN
technology as of today. Another well known is the
HiperLAN standard by ETSI. Both these
technologies are united under the Wireless Fidelity
(Wi-fi) alliance. In literature though, IEEE802.11
and Wi-fi is used interchangeably and we will also
follow the same convention in this paper. A
typical WLAN network consists of an Access
Point (AP) in the middle/centre and a number of
stations (STAs) are connected to this central
Access Point (AP).Now, there are basically two
modes in which communication can take place.
In the centralized mode of communication,
communication to/from a STA is always carried
over the APs. There is also a decentralized mode in
which communication between two STAs can take
place directly without the requirement of an AP in
an ad hoc fashion. WLAN networks provide
coverage up to an area of 50-100 meters. Initially,
Wi-fi provided an aggregate throughput of
11Mbps, but recent developments have increased
the throughput to about 54 Mbps. As a result of its
high market penetration, several amendments to
the basic IEEE 802 standard have been developed
or are currently under development.
In this paper, we overview the IEEE 802.11
standard and address the technical context of its
extensions. In section 2, we briefly discuss the
history behind the development of the standard.
Section 3 deals with the features of the IEEE 802
family which have already been implemented. In
the following Section 4, we look at other standards
besides IEEE 802.11a; IEEE 802.11b/g. In section
5, some of the upcoming standards are discussed
and some open issues with the IEEE 802.11
standard is given in section 6. The HiperLAN and
Answer:
Carrier-sense multiple access/collision avoidance
Which multiple access technique is used by IEEE 802.11 standard for wireless LAN? Explanation: CSMA/CA stands for Carrier-sense multiple access/collision avoidance. It is a multiple access protocol used by IEEE 802.11 standard for wireless LAN.