A presentation On a,b,g Wireless LAN, and Preented By Md.Masum Hossain Pranjal Sinha Md.Munis Varun Jain Anmol Jain Nsumbu Noe

What is Wireless LAN ? is an evolving family of specifications for wireless local area networks (WLANs) developed by a working group of the Institute of Electrical and Electronics Engineers (IEEE). There are several specifications in the family and new ones are occasionally added. All the specifications use the Ethernet protocol and Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) for path sharing is an evolving family of specifications for wireless local area networks (WLANs) developed by a working group of the Institute of Electrical and Electronics Engineers (IEEE). There are several specifications in the family and new ones are occasionally added. All the specifications use the Ethernet protocol and Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) for path sharing.

History There have been 5 major milestones in wireless internet communication. There have been 5 major milestones in wireless internet communication. – – Released in 1997, the original wireless protocol –802.11a – Released in late 1999 –802.11b – Released in late 1999 –802.11g – Released in mid 2003 –802.11n – Released in 2009

The ORIGINAL wireless protocol. The ORIGINAL wireless protocol. –Security implemented via WEP Wired Equivalent Privacy (Legacy) Wired Equivalent Privacy (Legacy) Provided Bandwidth Provided Bandwidth –1 or 2 Mbit/s due to use of CSMA/CA Relatively Unpopular Relatively Unpopular Low interoperability due to loose specifications Low interoperability due to loose specifications Used DSSS Used DSSS Considered Legacy and no longer used Considered Legacy and no longer used

802.11a One of two amendments to the original specification released simultaneously One of two amendments to the original specification released simultaneously Provided up to 54 Mbit/s bandwidth Provided up to 54 Mbit/s bandwidth Uses OFDM Uses OFDM –Orthogonal Frequency-Division Multiplexing Transmits a signal over several sub signals for higher efficiency Transmits a signal over several sub signals for higher efficiency

OFDM

802.11b Second of two amendments released in 1999 Second of two amendments released in 1999 Provided up to 11 Mbit/s bandwidth Provided up to 11 Mbit/s bandwidth Uses DSSS Uses DSSS –Direct-Sequence Spread Spectrum Transmits a signal over several sub signals for higher efficiency Transmits a signal over several sub signals for higher efficiency

DSSS

802.11a and b Both introduced at the same time Both introduced at the same time Both use CSMA/CA Both use CSMA/CA a a –Faster –More expensive to manufacture –Operated in 5Ghz band –Mainly used in industrial settings b b –Slower –Cheaper to manufacture –Operated in 2.4Ghz band. –Mainly used in residential settings

802.11g Pretty much the most common wireless network in use today. Pretty much the most common wireless network in use today. Operates on 2.4Ghz band Operates on 2.4Ghz band Provides up 54Mbit/s bandwidth Provides up 54Mbit/s bandwidth –108Mbit/s with special implementations Uses OFDM for modulation Uses OFDM for modulation Adopted quickly after release for cheap and high bandwidth Adopted quickly after release for cheap and high bandwidth

802.11n Newest member of the family. Newest member of the family. Has rated 600Mbit/s bandwidth Has rated 600Mbit/s bandwidth Introduces MIMO Introduces MIMO –Multiple-Input Multiple-Output OFDM Modulation OFDM Modulation –Uses higher frequencies for increased number of carrier waves

What’s ? is a communications specification that was approved in early 2002 by the Institute of Electrical and Electronics Engineers Standards Association (IEEE-SA) for wireless personal area networks (WPANs). The initial version, , was adapted from the Bluetooth specification and is fully compatible with Bluetooth is a communications specification that was approved in early 2002 by the Institute of Electrical and Electronics Engineers Standards Association (IEEE-SA) for wireless personal area networks (WPANs). The initial version, , was adapted from the Bluetooth specification and is fully compatible with Bluetooth 1.1

Let’s know about … is a group of broadband wireless communications standards for metropolitan area networks (MANs) developed by a working group of the Institute of Electrical and Electronics Engineers (IEEE) is a group of broadband wireless communications standards for metropolitan area networks (MANs) developed by a working group of the Institute of Electrical and Electronics Engineers (IEEE).

Continued… The original standard, published in December 2001, specified fixed point-to- multipoint broadband wireless systems operating in the GHz licensed spectrum. An amendment, a, approved in January 2003, specified non-line-of-sight extensions in the 2-11 GHz spectrum, delivering up to 70 Mbps at distances up to 31 miles. Officially called the WirelessMAN™ specification, standards are expected to enable multimedia applications with wireless connection and, with a range of up to 30 miles, provide a viable last mile technology. The original standard, published in December 2001, specified fixed point-to- multipoint broadband wireless systems operating in the GHz licensed spectrum. An amendment, a, approved in January 2003, specified non-line-of-sight extensions in the 2-11 GHz spectrum, delivering up to 70 Mbps at distances up to 31 miles. Officially called the WirelessMAN™ specification, standards are expected to enable multimedia applications with wireless connection and, with a range of up to 30 miles, provide a viable last mile technology.

Questions?