Wifi wimax

WI-FI AND WIMAX

OUTLINE Wireless Standards Introduction to Wi-Fi History How Wi-Fi works? Constituents of Wi-Fi Wi-Fi Standards Strengths & weaknesses of Wi-Fi Introduction to WIMAX Architecture WIMAX Standards Flavors of WIMAX Infrastructure of WIMAX Strengths & weaknesses of WIMAX

WIRELESS STANDARDS

INTRODUCTION TO WI-FI

WIFI stands for wireless fidelity

Brand licensed by the Wi-Fi Alliance

Based on IEEE 802.11a,b and g standards

Early 1980s, 1st wireless system was developed

After 1990, wireless technologies gradually widely accepted

Wi-Fi is a local area network technology that was originally thought to replace the thousands of miles of LAN cables

CONT…

WIFI is considered to be one of the first widely deployed fixed broadband wireless networks.

The Wi-Fi architecture consists of a base station that wireless hosts connect to in order to access network resources.

As long as the users remain within 300 feet of the fixed wireless access point, they can maintain broadband wireless connectivity.

ORIGIN OF WI-FI

The precursor to Wi-Fi was invented in 1991 by NCR Corporation in Nieuwegein, Netherland.

The first wireless products were brought on the market under the name WaveLAN with a speeds of 1 MB to 2 MB.

Vic Hayes has been named as father of “Wi-Fi’’.

HOW WI-FI WORKS ?

WHAT A WIRELESS NETWORK MADE UP OF:

Base stations, Access points, or Gateways

The base station sends and receives radio signals to and from the Wi-Fi radio in your laptop or PC.

Enabling you to share your Internet connection with other users on the network.

Access points and gateways have a wide range of features and performance capabilities, but they all provide this basic network connection service.

High gain Parabolic grid antennas to beam the signal to over 30km from tower to tower

Customer Premises equipment (CPE) to access the signal from the towers

Sector antennas to beam the signal from the towers to the community users

Other components that need to be installed in order to put the above systems together

TYPICAL COMMUNITY WI-FI CONSTITUENTS

WIFI STANDARDS

Standard Throughput Range Frequency

802.11a Up to 54 Mbps

Up to 300 ft

Between 5 and 6 Ghz

802.11b Up to 11 Mbps

Up to 300 ft

2.4 Ghz

802.11g Up to 54 Mbps

Up to 300 ft

2.4 Ghz

STRENGTHS OF WI-FI

Does not require regulatory approval for individual.

Wi-Fi allows local area network to deployed without wires for client devices

Wi-Fi can make access publicly available at Wi-Fi hotspots.

Users are able to be mobile for up to 300 feet from the access point.

There are many Wi-Fi compatible products that are available at a low cost and can interoperate with other network technologies.

WEAKNESSES OF WI-FI

Designed technically for short-range operations and basically an indoor technology

Low bandwidth compared to wired networks

Limited level of mobility

Susceptible to interference

Security is a concern

WIMAXWIMAX stands for Worldwide Interoperability for Microwave Access

The technology is specified by IEEE as 802.16 standard.

It is a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL.

WIMAX is expected to provide fixed, nomadic, portable and eventually, mobile wireless broadband connectivity without the need for direct line-of-sight (LOS) with a base station.

CONT…In a typical cell radius deployment of three to ten kilometers, WIMAX Forum Certified™ systems can be expected to deliver capacity of up to 40 Mbps per channel, for fixed and portable access applications.

Goal: Provide high-speed Internet access to home and business subscribers, without wires.

Mobile network deployments are expected to provide up to 15 Mbps of capacity within a typical cell radius deployment of up to three kilometers.

802.16 ARCHITECTURE

REFERENCE MODEL

Application

Transport

Network

Data Link

Physical

Medium

Data Link

Physical

Application

Transport

Network

Data Link

Physical

Data Link

Physical

Network Network

Radio

WIMAX STANDARDS

802.16 802.16a 802.16-2004

802.16e-2005

Date Completed

December 2001

January 2003

June 2004

December 2005

Spectrum 10-66 GHz < 11 GHz

< 11 GHz

< 6 GHz

Operation

LOS Non-LOS Non-LOS

Non-LOS and Mobile

Bit Rate 32-134 Mbps

Up to 75 Mbps

Up to 75 Mbps

Up to 15 Mbps

Cell Radius

1-3 miles 3-5 miles 3-5 miles

1-3 miles

FLAVORS OF WIMAX

INFRASTRUCTURE OF WIMAX

STRENGTHS OF WIMAXFaster than broadband service

Single station can serve hundreds of users

No more DSL installation fees

Much faster deployment of new users comparing to wired

networks.

Would allow gamers access to ad hoc local networks of

other players with the same gear- without any internet

connection.

WIMAX services are available in the rural area too

WEAKNESSES OF WIMAX

Line of sight is needed for longer connections.

Weather conditions like rain could interrupt the signal.

Big installation and operational cost which makes it expensive.

Bandwidth Shared Among Users

WIMAX network is very heavy in structure therefore need much electrical support for running the overall network.

Speed Decrease over Large Distance

When compared to other modes of broadband connectivity, for example, fiber optic cables and satellite internet, WIMAX is still slow

THANK YOU FOR YOUR COOPERATION !!!

BY:VARUN GUPTA