What Is Wireless Network Computer Science Essay

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

Wireless means data is transferred through the radio signal or infrared substitute of cables in the computer network connection. This is a modern communication technology than wired network connection. Having lots of advantages and disadvantages. IEEE 802.11 standards are using to configure the wireless network connection. Wireless network is easy and quick for access, Easy to configure in the environment. Possibilities are available for connect the several buildings apart from several kilometres. Economically cost effective than cable network connection. Wireless network adapter must require in each communication system which is used to configure the wireless communication. Nowadays most system has this adapter as a built-in feature (William Stallings 2007, p.524).

1.0.2. What is IEEE 802.11?

IEEE 802.11 standardizations are basics for most wireless network. Different forms of standards available in the IEEE 802.11.Rules of wireless communication are defined by these IEEE 802.11 standards. The first extension of IEEE 802.11 standards was approved in 1997 but its antiquated today.

The implementation of IEEE 802.11 standardization is available in two ways. First one is infrastructure mode, this method consist of one main station act as a master others are associated with that master. Master called as term of access point, this method of implementation is called as BSS. In BSS method of implementation, all the communication process happens through the AP (Access Point).If you want send message , first that message go to the access point then only it will transfer to the destination. In the second method of implementation, nothing likes master or stations. Communication process happens directly with the final destination. This method implementation termed as IBBS and popularly called as an ad-hoc network.

The below diagram illustrates some features of the popular standards of IEEE 802.11.


Data rate


802.11 a

54 Mbps

5.1-5.7 GHz

802.11 b

11/22 Mbps

2.4 GHz

802.11 g

54 Mbps

2.4 GHz

802.11 g Turbo

108 Mps

2.4 GHz

802.11 n

Up to 600 Mbps

2.4-5.8 GHz

Table 1 - features of the popular standards of IEEE 802.11

2.0. Difference between 802.11n and 802.11g

Two different wireless devices are very popular in the market, which are 802.11g protocol or newer 802.11n protocol. There are many different between these two wireless standards. If we used two standard N and G devices, most of the routers will support N will also support G - but N speed is faster than G.

2.0.1. Features of 802.11n

802.11n is a wireless standard that has gone through a rigorous updates for the past 5 years and still continued with its journey of updating. The latest manufactures of wireless devices in the store are based on the above wireless standard from year 2007 which has yet to get approved and finalized by the Institute of Electrical and Electronics Engineers (IEEE).

Wireless N uses the Multiple Input, Multiple Output a technology known as MIMO in the industry which operates with the maximum transmitting power and reception with the aid of multiple antennas. Provided that router transmits signal in full 802.11n mode it's stated that data transfer speed of 130 to 160 Mbps can be achieved with the listed maximum of 300 Mbps. But it's a hypothetical scenario since 802.11g device is also connected to the network.

802.11n devices are capable of operating on 2.4 or 5GHZ bands, but to utilize 5GHZ all linked devices should support 802.11n standard. Though the use of 5GHZ will have a negative impact on range. But this is ignorable as the benefits of using 5GHZ are vast. Especially less interference and more penetrating power through hard walls.

2.0.2. Features of 802.11g

802.11g was the fastest protocol until 802.11n came to existence. Though 802.11g has some pitfalls, such as compatibility issues with 802.11a devices which operate at 5GHZ band, in contrast 802.11g operates at 204GHZ, and 802.11g shares the band with many other different devices. But a slower 802.11b supports 802.11g as it can operate both 2.GHZ and 5GHZ bands.

Because 802.11g operates at 2.4GHZ, like many other common devices such as mobile phones, microwaves and Bluetooth, it causes considerable amount of interference. To exterminate the problem 802.11n was developed, and which can operate both at 2.4GHZ and 5GHZ bands. There is "Super-G" also available which based on 802.11g band and can reach speeds up to 108Mbps.

2.1. Primary 802.11g and 802.11n Specifications



Standard Approved

June 2003


Maximum Data Rate






RF Band


2.4GHz or 5GHz

Number of Spatial Streams


1, 2, 3, or 4

Channel Width


20MHz or 40MHz

Table 2 - primary 802.11g and 802.11n specification

(William Stallings 2007, p.543)

3.0. Cost and reliability

3.0.1. Cost influences in 802.11n Network architecture.

Today, to be organized a network particular amount of access point will be required based on the network requirement so the number of access points required in a network is largely determined by the ability of the network access points to connect the client devices. Better connection and links from clients will decrease the number of nodes required, which reduces not only the equipment costs but site purchase, installation, fixing and uncompleted maintenance costs. A network with fewer nodes is easier to organize and maintain

The 802.11n network, in expense we will have to spend tremendous amount of money and result will not be produced if the system is not properly solved or planned and managed moment at the same time as weakening to transport. The technology, though contribution tremendous revenue, could be an expensive and implement in experiment and mistake in addition little or missing access points may leave coverage holes and occur wearisome error while too many access points, aside beginning losing a pots of money, can result in self interference, cancelling out the benefits

Therefore the future review and considerations in architecting and inventing the next invention of WLAN are expenses and healthy presentation. MIMO technology and high bandwidth channels will be necessary to dependably convince the wider throughput difficulty of next creation applications.

3.1. Reliability and Performance

802.11n is a multifaceted technology presenting many design challenges and obstacles that affect signal quality. By satisfying signals throughout the signal chain to maintain signal performance and reliability, it becomes possible to design efficient systems which achieve higher throughput and greater range. In this way, the network would be designed or produced the highest-performing, most reliable and cost-effective 802.11n systems on the market (Broadcom.com).

The combined impact of implementing all of these improvements in concert is to create a system that provides the highest possible performance. However, to understand the true impact of sustaining the signal and improving reliability requires measurement of actual throughput. The wireless IEEE 802.11n standard was produced high-bandwidth and incredible capability to a wide range of typical applications. Through the capacity to sustain live video streaming, 802.11n makes best the home network with no wires and all but excludes the outstanding blocks to everywhere wireless performs in the work station and other areas (William Stallings 2007, p.647).

The wider presentation establishment of 802.11n is numerous inputs, several output (MIMO) technology which makes several transmit and collect antennas to produce a practical range of antennas that facilitate the communication of similar information streams. Nevertheless, at the same time as MIMO mounts up taken as a whole throughput, the MIMO signals can be agitated, building it complicated to continue wider perform wireless associates. If signals cannot be continued connecting the transmitter and receiver, sound and errors will influence presentation (Tash Hepting & David CohenTrapeze, 802.11n)

4.0. Technical aspects and challenges of implementation

The frequency band of 802.11n is 2.4GHz and 5GHz bands. This is having backward compatibility compare than other technology. This has several improvement technologies because of improve the range, throughput and consistency of the wireless LAN network. 802.11n has worked in physical, MAC layers and development to enable higher throughput. OFDM technology is used improve the maximum code rate and considerably wider bandwidth like 54Mbps.


Specification status

802.11n Primary specification



Maximum data rate 600Mbps

Space division multiplexing


Modulation DSSS/CCK/OFDM


Optional (antenna)

RF band 2.4GHz-5GHz

MIMO power save


No of spectral stream 1-4

Channel bonding(40MHz)


Channel width 20-40MHz





Greenfield mode


Table 3- Some component of the 802.11n

802.11n will have some certain technology such as multiple input multiple output, packet aggregation and channel bonding. MIMO- this is transmits multiple data streams on the same frequency with the help of space division multiplexing. Packet aggregation - it is used for data file transfer with the help of multiple data packets in single frame. Channel bonding- this is combination of two adjacent 20MHz in to single 40MHz channel. Finally it gives double the bandwidth.

4.1. Implementation

The technology will develop for the feature requirements. Such as improve throughput ,multiple or smart antenna, changes of signal encoding system and MAC access protocol and " improve the range at exiting throughputs increased resistance to interference more uniform coverage with in an area".(William stallings,P452)

Related to network implementation such as review requirements for WLAN, access the existing network, review the exiting Poe infrastructure and consider using 40MHz channel.

5.0. Advantage of the Standard.

 The IEEE 802.11n is the newly enhanced network standard which has amended the previous IEEE802.11 standards. The enhancement of this standard allows the data to more communicative effective than the previous ones, the purpose that to increase the communication of data among business enterprises, public and home uses since the increase of wireless technologies and use of multimedia contents.

The key advantages in these standards in the newly introduced features to the IEEE 802.11n standard. The multiple input multiple out, 40 MHZ channel to the physical layers and frame aggregation to the MAC layer. The MIMO feature allows the standard to provide point per access bandwidth functionality by increasing the bandwidth capacity from typical 56 Mbps to 300 Mbps. This makes a great differences and break through to wired network to wireless networks among a group of computers.

The coverage and reachable of the network access points has been benefit that it provide access by 2 times more than the previous standards. The IEEE 802.11n standard uses multiple antennas so it has a greater chance to intake waves from surfaces. The multiple uses of antennas also allow the diversity of using multiple paths where it increases the throughput of the technology. The capability of working with different standards allows this technology to co-exist with other standards as well. The popularity of the standards also makes this standard to its peak to success. Nowadays laptops also built with 802.11n adapters, and also added via USB interface.

The features of the previous standards are also included, such as radio management and WPA encryption for security purposes. The main objective is to increase the provision of the throughput of the network to the user. The change has been made in the MAC layer. The is standards also capitalise in packet framing aggregation methods where this concatenate several frames to one single frame, which increases the overall thought.


5.1. The technical challengers of the standard      


The fundamental drawback this system is that new technology is prone to more technical difficulties in the stage of implementing it. Most frequently and common requirements in nowadays technologies is that it should be compactable and durable to long term. In that case this standard uses the MIMO system which requires many antennas, that makes it spacious and bulky to operate. The next issue is that if more antennas are used more the power amplifiers are used in the devices; this may consume more energy and high maintenance to implement.

The characteristic of new technology is that is higher cost and incurs a high initial cost to develop it. But future implementation may get decrease the price as the more development is untaken. The backend network does not support the 10/100/1000 Mbps , the new technology requires new components such as patch panels, fibber interfaces, core switches need to be 1GE enabled to recognize the enhanced performance of 802.11n. The 802.11n adaptors only support if both client and network host share the same technology or else they should be upgraded. If not upgrade the adaptors the 802.11 b/g may bring down the performance of the client 802.11n adaptors. The operation of 802.11n is in 2.4 GHz it may be issue of overlapping whereas the other three non overlapping channels are taken by neighbouring access points and other radio operations, there may be a chance to overlapping if the spectrum is above 40 GHz.

Most of the switches and power injectors don't support the 802.11n because the minimum requirement is 17 watt power injector. Since the previous 802.3af don't support this the development may be experiencing great deal of changes and implementing new technologies while this may incur a cost to renovate this platform for this standard. The development and implementation of these standards are very challenging and incur great investment. And most of the companies already have invested in the previous standards which don't support the new 802.11n standard. This makes the development from changing the whole network plan of the organization as well as the peripheral devices. 



We worked out through the group effort to produce this assignment I particularly have chosen Cost and Reliability, and have brought my experience and ideas to make over the topic which I have been given to work. In an explanation the cost influences in a network comparatively than any other system for an example 802.11n is the next invention of wireless LAN technology which produces a spectacular and rapid swell in variety and through more than legacy 802.11a/b/g tools. Which I have already spoken in my topic again it needs to be explained and given a full description about 802.11n and Wi Fi, coming to the point.

802.11n is up and coming as a shows potential technology and a main technological advance for Wi-Fi networking. Its important produce in information rates and variety will eternally transform the way Wi-Fi networking is finished in the work station. The 802.11n technology will support all main platforms, together with consumer electronics, personal computing and handheld platforms, all through all most important project, home and public hotspot environments.

There are positively many applications today that needed access to several equipment place and points in remote hard access location and readily available support for these application could be produced by a common wireless terrestrial and satellite networks but particularly in the business environment the employment violates the desired cost requirement will be varied. This violation is the main reason to develop a special network for a special purpose they need introduced a new network system it should be low cost and robust infrastructures capable of producing services that kind of application

Mainly the cost constraints are always at the top of the list in implementing a network system such as Wi Fi and the feasibility assessment should be made before we produce our plan and design a system. Wi-Fi is rapidly growing a fundamental access technology for the enterprise nowadays around the world and 802.11n is a key element which will make faster this transition. With the enterprise's increasing use of Wi-Fi, the need for a robust and reliable wireless network becomes paramount.

The primary and key thing for wireless network administrator has to design a network which delivers both top performance and a level of reliability should be suitable for the organization's most important network applications. 802.11n can deliver the raw technology to make this a reality, but in order to properly utilize it so we need to carefully plan our deployment and proper root path planning.

And the types of clients are also influence in the cost of the network for an example we have the ability to perform on "can do" scenarios to see how coverage and capacity can be allocated for different budget levels and different service offerings, such as data, guest access and voice. The end result is an accurate plan that leverages 802.11n technology as it applies to our needs and budget, without excessive cost in time, labour, or dollars

Next to be discussed about reliability and the performance of 802.11n further more what kind of services it actually provides and how or why people more involved or much interest in choosing this technology which are, I am going to explain by giving some examples and expressing information which I have gone and gathered from different source like book and useful website. I would mention those sources later on in my reference, back to the point and talk about reliability and performance, for an example I have given below which I have already gone through I think this could be very useful to know about the Wi Fi technology

Demand for wireless LAN hardware has experienced unique increase throughout the earlier period, developing rapidly from originality into requirement. As an quantify of this growth, WLAN chipset shipments in 2005 surpassed the 100-million-unit mark, a more than tenfold increase from 2001 shipments of a reduced amount of than 10 million units. Thus far, require has been determined mainly by users linking notebook computers to networks at occupation and to the Internet at house at the same time as at coffee shops, airports, hotels, and other mobile assembly places. As a result, Wi-Fi technology is most commonly found in notebook computers and Internet access devices such as routers and DSL or cable modems. In piece of evidence, additional than 90 percent of all notebook computers now ship with built-in WLAN. [1 Ref]

The growing popularity of Wi-Fi is serving to expand the technology further than the PC and into user electronics applications like Internet telephony, music, gaming, and even photo presentation and in home video broadcast. Personal video recorders and other A/V storage appliances that bring together satisfied in one spot for delight roughly the home are moderating this development.

This is actually people expect the benefit from Wi Fi technology and reality let me explain the performance and how it provides the service. This is talented through multiple input/multiple output (MIMO) radio technologies, bonding bordering 20 MHz wide channels collectively for superior bandwidth 40 MHz wide channels, and proficiency enhancements to the fundamental 802.11 protocol itself. at the same time as donation consumers will knowledge a humble expand in variety, the full bang of 802.11n isn't felt with no both 802.11n competent consumers and access points.

One of the mainly identified mechanisms of the draft requirement is well-known as Multiple Input Multiple Output, or MIMO. MIMO gives a radio wave practice called multipath transmitted in sequence bounces off walls, doors, and other objects, realization the receiving antenna multiple times through different routes and at faintly unlike times. Abandoned, multipath distorts the unique signal, building it extra complicated to make intellect of and corrupting Wi-Fi presentation. MIMO harnesses multipath with a technique recognized as space separation multiplexing. The transmit WLAN device actually provides a data stream into various parts, called spatial streams, and transmits every spatial stream from side to side divide antennas to matching antennas on the delivery end. The present 802.11n draft produces for up to four spatial streams, although accommodating hardware is not necessary to maintain that many. [2 Ref]

Finally I come to the conclusion this module and the information which I have used in this assignment is most useful and important to acknowledge this technology and up to me I have gather lots of information which I can say they were really useful for me to support me ideas to improve my work particularly in this assignment I have given some reference below as I said earlier, could be useful