wireless project 000229396

8/3/2019 Wireless Project 000229396

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Introduction:

Wi-Fi Stands for Wireless Fidelity. Wi fi is one of the connectivity’s. It is one of standard for

connecting electronic devices through wireless networking. Wi Fi allows devices such as

mobiles, laptops, P.C’s etc. to connect to the internet without cables. One can download and

upload data through Wi-Fi by simply connecting to a network. Wi-Fi helps us a lot; when we are

out of home i.e. restaurant, MC Donald’s etc.

One of the researches states that one person in ten all over the globe use Wi-Fi at home and

works. Today over 700 million people use Wi-Fi. There are about 800 million new Wi-Fi

devices are added every year.

Wi-Fi Logo Structure of Wi-Fi

Wi-Fi is developed by Wi-Fi alliance, as one of the global non-profit organization to create a

single worldwide standard for high speed wireless local area networking. Wi-Fi certified

program was introduced in quarter of 2000. Wi-Fi alliance has done more than 10000 product

certificate until today.

The Wi-Fi missions are:

To develop best user experience by using

Grow the Wi-Fi market across market segment,on a variety of devices.

To develop market enabling programs.

To support industry agreed standards & specifications.



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Timeline of Wi-Fi:

(Image source: Wi-fi.org)



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Etymology:

Wi-Fi stands for Wirless fidelity, which resembles Hi-Fi which stands for high fidelity which

was a term used by audiophiles to differ high quality sound from poor quality sound.High

fidelity sound had low amount of noise and distortion.

Wi-Fi technology categorization :

Narrowband microwave LANs: They operate at microwave frequencies

Infrared LANs which operate at 1 and 2 Mbps and at wavelength at 850nm and 950nm

Direct sequence spread spectrum that operates in 2.4 Ghz band. It has a data rate of 1Mbps and 2

Mbps.

Frequency Hopping spread spectrum- It operates in 2.4Ghz , and data rates of 1 Mbps and

2Mbps.

DSSS and FHSS operate in ISM bands, so they require no licensing.

Wi-Fi attributes:

Few of the attributes include,

Roaming-They need to roam freely in their service area.

Dynamic- The addition of new stations should not affect users. Similarly the deletion and

relocation should not affect any other users.

Throughput-As the bandwidth is decreased ,the Mac protocol has to make the efficient use of the

available bandwidth as much as possible. High throughput can be achieved by using the MIMOto boost data rates to 600 Mbps through multiple antennas.

The application include: HD streams, home , entertainment,online gaming etc. They are

backward compitable with 802.11a/b/g.

Configuration of Wi-Fi:

There are two types of Wi-Fi configuration:

i. Ad hoc configuration

ii. Infrastructure configuration.



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In Infrastructure mode , wireless network joins to a wired network such as Ethernet.It uses a

central access point to form a network. Packets are transmitted from a wireless node to the access

point, which controls further switching/routing.

BSS and ESS are two different classes of infrastructure mode. BSS stand for Basic

Service Set where a node is associated with an access point, and this is consistent, where as in

Extended service set a mobile node is present which can roam around and link up with access

point.

In adhoc mode, a peer to peer connection is setup, in which a group of devices with 802.11 NICs

can create a network and communicate in between themselves without any infrastructure. One of

the drawbacks is that the network is limited to the peers.

Working of Wi-Fi:

Wi Fi enabled devices connect to internet using a wireless network range called hotspot.Hotspots

may vary from a small coffee shop to a shopping mall. There may be hotspots of free and paid.

Currently,there are around four million hotspots around the world.

Hotspot



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IEEE 802.11 is set of standards for wireless communication in 2.4,3.6,5 Ghz freq bands.They are

maintained by LAN/MAN standard committee.The current version Is IEEE 802.11-2007.The

IEEE 802.11 family is a series of air modulation techniques that use the same basic protocol.The

802.11 family of specifications was developed by IEEE for wireless LAN.

Some of the Specifications of 802.11:

802.11- It provides 1 or 2 Mbps transmission in the 2.4 GHz band by the use of FHSS or DSSS.

802.11a- provides rates for 54Mbps in the 5Ghz band.

802.11b-it provides a data rate of 11 Mbps in 2.4Ghz band.

802.11g- it provides 20+Mbps in 2.4Ghz band.

Setup of Wi-Fi has one or more access points and many clients. One of the accesss point

broadcasts its SSID in beacons i.e packets ,which are broadcasted for every 100ms.The data rate

of these beacons is 1 Mb/s. Depending on the settings, the client may decide whether to join the

particular access point or not.

Services of Wi-Fi:

Wi-FI provides following services

Association- It provides and association between a station and AP inside a BSS.

Reassocation- It allows the transfer of one AP to another, which allows the mobile station to

move from one BSS to other BSS.

Disassociation- This provides an notification that an existing connection is terminated .This

could be in either way.



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Authentication- Used for security purposes.This identifies stations to each other.

Privacy – The privacy is used to protect content from eavesdropping.

Advantages and Disadvantages:

Advantage of Wi-Fi is that it doesn’t require any cables, which reduces the cost of

infrastructure. This is more effective when they cannot be run into large buildings and

hilly areas.

Wi Fi doesn’t require any license as it uses unlicensed radio deploys. One of the Wi-Fi

advantages is that it allows roaming. Any device can connect to any network.

Set of global standards are set for WI fi which are similar all around the globe.

Disadvantages:

Spectrum allocations and operational limitations are consistent worldwide.

Devices using Wi Fi consume more battery.

The security of Wi-Fi is a concern as WEP can be breakable if it is correctly configured.

Challenges:

Security challenge in Wi-Fi is most important challenge in Wi- Fi,

Wi fi differs in its simplified access from its wired network .Breaking into a wireless

network is easy compared to wired network, as they have firewalls. In one of the

examples, Mike Outmesguine (who has a technical services company) with the help of a

laptop in the passenger seat of his Toyota 4Runner and an antenna on the top, set out to

sniff wireless networks between Los Angeles and San Francisco In his eight hundred

mile drive he confirmed that the number of wireless networks is growing rapidly, he also

found that only a third used basic encryption – a key security measure.

An attacker who breaks into a wi fi network can send a spoof response to any user in the

same network, before the DNS server replies.

Piggybacking is another security problem in Wi-Fi. It is the unauthorized access of ones

wireless network, by others computer. Wi-Fi can also lead to middle man attack, wherethe sensitive data sent by the user who joins a insecure network to login into a website,

can be obtained by a middle man before reaching the destination.



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Solutions:

WEP- Wired Equivalent Privacy:

One of the schemes to secure Wi-Fi is WEP. When messages are being transferred through radio

signals, they are prone to eavesdropping. This technology uses RC4 for confidentially and CRC-32 checksum for integrity. 64-bit uses a 40 bit key, to which a 24 bit initialization vector(IV) is

reduced to form RC4 traffic key. WEP was susceptible to attacks and poorly implanted by

vectors. WEP is superseded by,

WI-FI protected access (WPA)

IEEE 802.11i standard (WPA2) .

WPA(Wi-Fi protected access):

Wi-Fi protected access is much more improved standard It provides high level security,

producing enterprise and consumer Wi-Fi provides assurance that only authorized users canaccess their wireless networks. It is a powerful technology for Wi-Fi networks.It provides

encryption and user authentication. It has two versions- WPA personal and WPA-Enterprise.

WPA-Personal protects unauthorized access by having a set up password.

WPA-Enterprise is for large companies. The company can verify through a server.It uses 128 bit

encryption keys and dynamic session keys. Data is encrypted using RC4 stream cipher, with a

128 bit key and 48 bit initialization vector. A major improvement was achieved in WPA over

WEP is the Temporal Key Integrity Protocol(TKIP),which changes keys as the system is used.It

also provides with improved payload.

One of the drawbacks is that CRC used in WEP is no secure, it can be altered and the message

can be updated without the help of WEP key. Hence a more secure authentication code is used in

WPA, named “Michael”.

WPA 2 :

It is certified form of IEEE 802.11i tested by Wi-Fi alliance.It replaces the Michael Code by

message authentication code, which is fully secure. The Rc4 will be replaced by AES(Advanced

Encryption Standard).

Similar to WPA ,WPA2 has two authenciation modes:Personal and Enterprise mode ,which is

designed for home and office networks.It generates a 256 bit key from a plain text phrase which

can also be called as PSK.



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Latest developments in Wi-Fi:

Super Wi-Fi: This term is defined by FCC of the United States of America to create wireless

networking technologies for longer distances. The main idea of Super Wi-Fi is using of white

spaces(i.e. frequencies that have approved for broadcasting but not used) in between the

television frequency channels. The FCC has opened a new unlicensed spectrum, between therange of 50 MHz and 700Mhz.As TV channel frequencies are low compared to the 2.4Ghz freq

of the regular Wi-Fi, they penetrate and travel more further. In first quarter of 2011, Rice

University, in association with Technology For All(A non-profit organization), installed super

Wi-Fi in a residential area near East Houston, Texas.

One of the effects of Super Wi-Fi is it uses the frequencies that have been left out by the

digitalization of TV channels. But these may have a profound impact on microphones, telemetry

particularly medical field.

Non-Wi-Fi-Alliance wireless technologies for fixed points are called as fixed wireless (MotorolaCanopy). Non-Wi-Fi-Alliance wireless technologies for mobile use are usually described

as 3G, 4G or 5G.

Some of the latest developments of Wi-Fi are,

WIFI triangulation to monitor and track the location of the people who are connected in

a particular campus.

Using dual radio Access Points and dedicating 2.4GHz to connect clients and the 5GHz

radio as backhaul for the traffic.

Combining WIFI and cellular boosting technology without the need for additionalequipment

The improvements that are being developed in Wi-Fi are,

Firewall functionality

Increased security for managment hardware to Access Point

Design of Integrated 'Rogue Detection' systems

Creating a Mesh Access Point networking

To provide VOIP mobility

Network access control

Secure remote access to company network `

In 2010, Wi-Fi technology has spread vastly within commercial and industrial sites.The main

advantage of this is that it provides roaming and reduces the cost of infrastructure. It also enables

WVOIP. Wi-Fi is undergoing lot of changes by moving towards thin access points for indoor

use, and mesh topologies for outdoor use.



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REFERENCES:

http://en.wikipedia.org/wiki/Wi-Fi

www.wi-fi.org

www.bwif.org

www.wifihelps.com



http://www.wi-fi.org/


http://www.bwif.org/


http://www.wifihelps.com/






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