sanjay wifi project iimt pune
DESCRIPTION
I, SANJAY SINGH here by declare that this project is therecord of authentic work carried out by me during theacademic session 2006-2008 and not been submitted toany other university or institute towards the award of anydegree.TRANSCRIPT
INDIAN INSTITUTEOF
MANAGEMENT TRAINING
A PROJECT REPORT
ON
“STUDY OF WI-FI NETWORK”
WITH THE RFFERENCE
OF
DYNAMIC LOGISTICS PVT. LTD.2007
SUBMITTED TO THE: SUBMITTED BY:SANJAY SINGH
(IIMT PUNE)
UNDER THE GUIDANCE OF:MR. SHREESH PATWARDHAN (VP IT)
MR. ASHUTOSH KESKAR (SYSTEM ADMINISTRATOR)DYNAMIC LOGISTICS PVT. LTD., PUNE
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ACKNOWLEDGEMENT
I wish to acknowledge my specific indebt ness to director “INDIAN INSTITUTE OF MANAGEMENT TRAINING”, who made this opportunity to perform summer training as a part of MBA Course.
I wish to extend my Sincere Gratitude towards “Mr. SHREESH PATWARDHAN” (Vice President DYNAMIC LOGISTICS PVT. LTD. PUNE) for accepting me as a summer trainee and assigning this project to me.
I am extremely grateful to Mr. ASHUTOSH KESKAR for their valuable guidance and best possible help during project.
I am extremely grateful to Mrs. Bonisha for their valuable guidance and best possible help during course of study.
I am deeply grateful to my parent’s who have given me every help and moral support and their constant advice which enabled me to pursue my academic aim.
Thanks to other summer trainees for their co-operation and suggestions through out this project.
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PREFACE
“Learning categorizes you and practicing on that learning specializes
you”.
Theoretical concepts taught and discussed in the classroom prove
useful if they have to remain relevant. Practice orientation of
management student is must generating competence to deal with
issues at grass root level it is for this reason that one month training
project study is prescribed as apart of syllabus for MDA in IASE
University.
This training is the mode of imparting practical training to the student.
The objective is to provide a deep insight into practical aspects of the
functioning of the organization. The trainer apprises the student to the
actual function, responsibility and problem faced by an organization. It
provides him with the knowledge of the various kind of problem that
crop up in the day to day functioning of the organization .The way they
are solved by the departments and appraisal of the crucial decision
taken by the manager at the crucial time.
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I was fortunate enough to complete my training at DYNAMIC LOGISTICS
PVT. LTD. This has given me an altogether new experience, which
would be immense help to me in my days to come.
INDEX1. EXECUTIVE SUMMARY 5
2. INTRODUCTION 6
a. COMPANY HISTORY
b. MISSION
c. VISSION
3. OBJECTIVE OF THE STUDY 12
4. INTRODUCTION OF WIRELESS NETWORK 13
a. WHAT IS WIRELESS NETWORK 14
b. TYPE OF WIRELESS NETWORK 15
c. HISTORY 16
d. ADVANTAGE AND DISADVANTAGE 17
e. USES OF WIRELESS NETWORK 19
f. NEED OF WIRELESS NETWORK 20
5. FEASIBILITY STUDY 22
6. WI-FI 24
a. MEANING OF THE TERM WI-FI 25
b. USES OF WI-FI ` 26
c. ADVANTAGES AND DISADVANTAGE 27
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d. MANUFACTERER OF WI-FI DEVICES 30
7. DIFFERENT TYPE OF WIRELESS NETWORKS & THERE LIMITATION. 39
8. TYPE OF WIRELESS NETWORK EQUIPMENT 45
9. WIRELESS STANDERED 51
10. TYPES OF WIRELESS ROUTER AND ACCESS POINTS 56
11. OPPORTUNITY AND CHALLENGES 81
12. CONCLUTION 82
13. PERSONAL COMPUTER MANAGEMENT & INDEXING 84
14. QUESTIONS RELATED TO WI-FI NETWORK. 91
15. BIBLOGRAPHY 105
EXECUTIVE SUMMARY
The Project on Study of WI-FI Network Carried at Dynamic Logistics Pvt. Ltd. Pune. ()
Project Title : Study of WI-FI Network
Place : Pune
Duration : 3 Months
Guided By : Mr. Shreesh Patwardhan (VP IT)Mr. Ashutosh Keskar (System Administrator)Dynamic Logistics Pvt. Ltd. Pune.
UNDERTAKEN BY:
SANJAY SINGH MASTER IN BUSINESS MANAGEMENT INDIAN INSTITUTE OF MANAGEMENT TRAINING, PUNE
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INTRODUCTION
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DYNAMIC LOGISTICS PVT. LTDPune- Alandi road, Dighi,
Pune.
Dynamic Logistics Pvt Ltd is an ICD company. Talera group set up this
company in 1983. ICD dighi is a one branch of this company. ICD dighi, pune
operational since October 1998.Starting modestly as a simple warehousing company,
today it is recognized as the pioneering giant that role of third party logistics (3PL)
services in the country. Dynamic logistics provides a vast array of services to various
brand established clients in multi-location. By providing the expertise with inventory and
distribution management, which extend to over 600destination in India and abroad, it has
catapulted as the industry leader in 3PL services. It is the first ISO-9002 complaint
logistics provider in India and has upgraded the standard to the current ISO-9001 –2000.
The company’s corporate office and operation base is in pune, India, a city
which is well connected by road, rail & air is ideally located near all major industrial
hubs which seek the specialized services, & is also in proximity to the port city Mumbai
which facilitates the exim trade. The 3PL services in pune are currently operated from
three centers, and the company is also represented for very esteemed and established
clients in chennai, Indore, and Aurangabad. Besides the logistics services, the company
also operates in pune the inland container depot or the dry-port facility with custom
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bonded warehouses and the provision for clearings ship and air cargo which is boon to
hinterland based importers and exporters. With an enviable growth record since
inception, Dynamic logistics is poised to take on the huge BPO demand headlong and
redefined the logic of logistics in India.
INFRASTRUCTURE
78000 sq.ft of bonded warehouses
22000 sq.ft import warehouse
17000 sq.ft export warehouse
30000 sq.ft open bonded area
1000 TEUs container yard
60 ton weighbridge/45 ton cranes
FACILITIES
Single window clearance
Panel of 62 transporters
39 airlines represented
28 shipping line represented
All draw back schemes with TRAs
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Communication and IT support
Buffer yard-No charges
Reefer charging point
Bank of Maharashtra, Vishrantwadi special timing 13:00 to 16:30 hours
for the payment of customs duty.
CLIENTS OF ICD DIGHI
Parag milk& milk product
Kimberly Clarke lever
Hindustan Antibiotics
Kinetic engineering
Bajaj Tempo
Tata International
Finolex
Sandoval Asia
Praj Industries
Thermos
Thyssenkrupp Industries
Vishay Components
Cummins India
Kirlosker Copeland
Fleet guard Filters
Spaco Carburators
Bajaj Auto
Roj Enterprises
Shigote Foods
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Weikfield
EXIM LOGISTICS
The inland container department Dighi, Pune is well-connected dry port by road and rail
to the gateway port of Nhava sheva international container terminal and Mumbai. it is
located 15 kms. From pune on pune-alandi highway & 5 km. From pimpri chinch wad
industrial area. it is also in close to the industrial belts of pune like hadapsar, chaken,
hinjewadi,ranjangaon,urse,phursungi and pirangilt
OPERATIONAL AREA IN ICD.
1. Gate Complex-Regulates the entry and exits of road vehicles carring cargo and
containers thro the terminals. It is place where documentation, security and container
inspect procedure are undertaken.
2.Container Yard-occupies the largest area in the India is shaking area where the export
to dispatch to port, import containers are stored till custom clearance and where empties a
weight onward movement like wise some stacking areas are earmarked for keeping
special containers such as refrigerated, hazardous, overweight/over length etc.
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3.Warehouse- A covered space/shades where export cargo is received and import cargo
stored/delivered, containers are consolidated and import less than container load are
unpacked and cargo is physically examined by customs, export and import consignment
are generally handled either at separate areas in a warehouse or different nominated
warehouse.
MISSION
To enable our clients to significantly improve their performance capability and to be
proactive by managing change, providing them with world class, cost effective and
highly efficient enabled logistic service.
VISSION
To be the preferred business partner to organization striving for dramatic improvements
in performance.
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OBJECTIVE OF THE STUDY
MAJOR
“To Study of Wi-Fi Network and Established the Wi-Fi Network Connection in the Organization.”
MINOR
1. To Study of Wireless Network and Wireless network devices.
2. To Study about Personal computer management (system
management) according to the user needs and there configuration.
3. To indexing the Computer Hardware devices according to their high
configuration to low configuration.
4. To Study the backup policy of the computer system.
5. To Study the different type of servers.
6. To Study the virus protection system.
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INTRODUCTION
TO
WIRELESS NETWORK
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WIRELESS NETWORK
While the term wireless network may technically be used to refer to any type of network that is wireless, the term is most commonly used to refer to a telecommunications network whose interconnections between nodes is implemented without the use of wires, such as a computer network (which is a type of communications network). Wireless telecommunications networks are generally implemented with some type of remote information transmission system that uses electromagnetic waves, such as radio waves, for the carrier and this implementation usually takes place at the physical level or "layer" of the network.
TYPES OF WIRELESS NETWORK
Wireless LAN
One type of wireless network is a WLAN or Wireless Local Area Network. Similar to other wireless devices, it uses radio instead of wires to transmit data back and forth between computers on the same network.
Global System for Mobile Communications (GSM)
The GSM network is divided into three major systems which are the switching system, the base station system, and the operation and support system (Global System for Mobile Communication (GSM)). The cell phone connects to the base system station which then connects to the operation and support station; it then connects to the switching station where the call is transferred where it needs to go (Global System for Mobile Communication (GSM)). This is used for cellular phones, is the most common standard and is used for a majority of cellular providers.
Personal Communications Service (PCS)
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PCS is a radio band that can be used by mobile phones in North America. Sprint happened to be the first service to set up a PCS.
D-AMPS
D-AMPS, which stands for Digital Advanced Mobile Phone Service, is an upgraded version of AMPS but it is being phased out due to advancement in technology. The newer GSM networks are replacing the older system.
Wi-Fi Wi-Fi is a commonly used wireless network in computer systems which enable connection to the internet or other machines that have Wi-Fi functionalities. Wi-Fi networks broadcast radio waves that can be picked up by Wi-Fi receivers that are attached to different computers. Fixed Wireless Data
Fixed wireless data is a type of wireless data network that can be used to connect two or more buildings together in order to extend or share the network bandwidth without physically wiring the buildings together.
Wireless LAN
The notebook is connected to the 54 MBit WLAN PCI Card (802.11g) Wireless access point using a PC Card wireless card.
A wireless LAN or WLAN is a wireless local area network, which is the linking of two or more computers without using wires. WLAN utilizes spread-spectrum or OFDM (802.11a) modulation technology based on radio waves to enable communication between devices in a limited area, also known as the basic service set. This gives users
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the mobility to move around within a broad coverage area and still be connected to the network.
For the home user, wireless has become popular due to ease of installation, and location freedom with the gaining popularity of laptops. Public businesses such as coffee shops or malls have begun to offer wireless access to their customers; some are even provided as a free service. Large wireless network projects are being put up in many major cities.
History
In 1970 University of Hawaii, under the leadership of Norman Abramson, developed the world’s first computer communication network using low-cost ham-like radios, named ALOHAnet. The bi-directional star topology of the system included seven computers deployed over four islands to communicate with the central computer on the Oahu Island without using phone lines.
"In 1979, F.R. Gfeller and U. Bapst published a paper in the IEEE Proceedings reporting an experimental wireless local area network using diffused infrared communications. Shortly thereafter, in 1980, P. Ferrert reported on an experimental application of a single code spread spectrum radio for wireless terminal communications in the IEEE National Telecommunications Conference. In 1984, a comparison between Infrared and CDMA spread spectrum communications for wireless office information networks was published by [ Kaveh Pahlavan ] in IEEE Computer Networking Symposium which appeared later in the IEEE Communication Society Magazine. In May 1985, the efforts of Marcus led the FCC to announce experimental ISM bands for commercial application of spread spectrum technology. Later on, M. Kavehrad reported on an experimental wireless PBX system using code division multiple access. These efforts prompted significant industrial activities in the development of a new generation of wireless local area networks and it updated several old discussions in the portable and mobile radio industry.
The first generation of wireless data modems was developed in the early 1980's by amateur communication groups. They added a voice band data communication modem, with data rates below 9600 bit/s, to an existing short distance radio system such as a walkie talkie. The second generation of wireless modems was developed immediately after the FCC announcement in the experimental bands for non-military use of the spread spectrum technology. These modems provided data rates on the order of hundreds of kbit/s. The third generation of wireless modem aimed at compatibility with the existing LANs with data rates on the order of Mbit/s. Several companies [developed] the third generation products with data rates above 1 Mbit/s and a couple of products [had] already been announced [by the time of the first IEEE Workshop on Wireless LANs].
"The first of the IEEE Workshops on Wireless LAN was held in 1991. At that time early wireless LAN products had just appeared in the market and the IEEE 802.11 committee
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had just started its activities to develop a standard for wireless LANs. The focus of that first workshop was evaluation of the alternative technologies. the technology [was] relatively mature, a variety of applications [had] been identified and addressed and technologies that enable these applications [were] well understood. Chip sets aimed at wireless LAN implementations and applications, a key enabling technology for rapid market growth, [were] emerging in the market. Wireless LANs [were being] used in hospitals, stock exchanges, and other in building and campus settings for nomadic access, point-to-point LAN bridges, ad-hoc networking, and even larger applications through internetworking.
Advantage of Wireless Network
The popularity of wireless LANs is a testament primarily to their convenience, cost efficiency, and ease of integration with other networks and network components. The majority of computers sold to consumers today come pre-equipped with all necessary wireless LAN technology.
The benefits of wireless LANs include:
Convenience: The wireless nature of such networks allows users to access network resources from nearly any convenient location within their primary networking environment (home or office). With the increasing saturation of laptop-style computers, this is particularly relevant.
Mobility: With the emergence of public wireless networks, users can access the internet even outside their normal work environment. Most chain coffee shops, for example, offer their customers a wireless connection to the internet at little or no cost.
Productivity: Users connected to a wireless network can maintain a nearly constant affiliation with their desired network as they move from place to place. For a business, this implies that an employee can potentially be more productive as his or her work can be accomplished from any convenient location.
Deployment: Initial setup of an infrastructure-based wireless network requires little more than a single access point. Wired networks, on the other hand, have the additional cost and complexity of actual physical cables being run to numerous locations (which can even be impossible for hard-to-reach locations within a building).
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Expandability: Wireless networks can serve a suddenly-increased number of clients with the existing equipment. In a wired network, additional clients would require additional wiring.
Cost: Wireless networking hardware is at worst a modest increase from wired counterparts. This potentially increased cost is almost always more than outweighed by the savings in cost and labor associated to running physical cables.
Disadvantages of Wireless Network
Wireless LAN technology, while replete with the conveniences and advantages described above, has its share of downfalls. For a given networking situation, wireless LANs may not be desirable for a number of reasons. Most of these have to do with the inherent limitations of the technology.
Security: Wireless LAN transceivers are designed to serve computers throughout a structure with uninterrupted service using radio frequencies. Because of space and cost, the antennas typically present on wireless networking cards in the end computers are generally relatively poor.
Range: The typical range of a common 802.11g network with standard equipment is on the order of tens of meters. While sufficient for a typical home, it will be insufficient in a larger structure. To obtain additional range, repeaters or additional access points will have to be purchased. Costs for these items can add up quickly. Other technologies are in the development phase, however, which feature increased range, hoping to render this disadvantage irrelevant.
Reliability: Like any radio frequency transmission, wireless networking signals are subject to a wide variety of interference, as well as complex propagation effects (such as multipath, or especially in this case Rician fading) that are beyond the control of the network administrator. In the case of typical networks, modulation is achieved by complicated forms of phase-shift keying (PSK) or quadrature amplitude modulation (QAM), making interference and propagation effects all the more disturbing. As a result, important network resources such as servers are rarely connected wirelessly.
Speed: The speed on most wireless networks (typically 1-108 Mbit/s) is reasonably slow compared to the slowest common wired networks (100 Mbit/s up to several Gbit/s). There are also performance issues caused by TCP and its built-in congestion avoidance. For most users, however, this observation is irrelevant
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since the speed bottleneck is not in the wireless routing but rather in the outside network connectivity itself. For example, the maximum ADSL throughput (usually 8 Mbit/s or less) offered by telecommunications companies to general-purpose customers is already far slower than the slowest wireless network to which it is typically connected. That is to say, in most environments, a wireless network running at its slowest speed is still faster than the internet connection serving it in the first place. However, in specialized environments, the throughput of a wired network might be necessary. Newer standards such as 802.11n are addressing this limitation and will support peak throughputs in the range of 100-200 Mbit/s.
Uses of wireless network
Wireless networks have significantly impacted the world as far back as World War II. With the use of wireless networks, information could be sent overseas or behind enemy lines easily and quickly and was more reliable. Since then wireless networks have continued to develop and its uses have significantly grown. Cellular phones are part of huge wireless network systems. People use these phones daily to communicate with one another. Sending information over seas is only possible through wireless network systems using satellites and other signals to communicate across the world otherwise getting information Emergency services such as the police department utilize wireless networks to communicate important information quickly. People and businesses use wireless networks to send and share data quickly whether it be in a small office building or across the world. Another important use for wireless networks is as an inexpensive and rapid way to be connected to the Internet in countries and regions where the telecom infrastructure is poor or there is a lack of resources, like most Developing Countries.
Wireless networks allow you to eliminate messy cables. Wireless connections offer more mobility, the downside is there can sometimes be interference that might block the radio signals from passing through. One way to avoid this is by putting the source of your wireless connection in a place where the signal will have as little interference as possible. Sometimes nearby networks are using the same frequencies, this can also cause interference within the network and can reduce its performance.
Compatibility issues also arise when dealing with wireless networks. Different components not made by the same company may not work together, or might require extra work to fix compatibility issues. To avoid this, purchase products made by the same company so that there are fewer compatibility issues.
Wireless networks, in terms of internet connections, are typically slower than those that are directly connected through an Ethernet cable. Though the speed is slower, most things will still move at the same speed except for things like video downloads. Though wireless
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technology continues to develop, it is now easier to get networks up and running cheaper and faster than ever before.
A wireless network is more vulnerable because anyone can try to break into a network broadcasting a signal. Many networks offer WEP - Wired Equivalent Privacy - security systems which have been found to be vulnerable to intrusion. Though WEP does block some intruders, the security problems have caused some businesses to stick with wired networks until security can be improved. Another type of security for wireless networks is WPA - Wi-Fi Protected Access. WPA provides more security to wireless networks than a WEP security set up. The use of firewalls will help with security breaches which can help to fix security problems in some wireless networks that are more vulnerable.
Need of Wireless Network
Personally, I could probably come up with more than 5 wireless network reasons, but these are the most important ones.
I believe that wireless networks represent one of the most significant inventions in human history - almost as important as sliced bread. Now, seriously, bread is certainly easy enough to cut yourself, but try to wire up a network and you will think of this invention in a different way. Just to make the whole picture clearer for you, let me give you five reasons why using a wireless network is definitely worth it.
Share Internet Access
With wireless networking, you can easily and cheaply share one single Internet connection among different computers, without having to use more modems. If that wasn't enough, you can even include new computers in your network only by using a wireless card and switching them on to have an immediate Internet connection! Not many wired networks would be able to do that.
Share Files and Printers
A wireless network guarantees access to your files regardless of where you are within your house, and with a home computer it also facilitates the synchronization of data on a laptop. Using wireless networks makes it so much simpler to send files between computers as compared to the traditional emails or CDs.
Moreover, if your printer is connected, you can write your documents anywhere you want and finally print them through a printer connected to another computer. In other words, a printer plugged into one of the computers on the network is available to all the computers saving you the expense of having multiple printers at home.
Play Games
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As might have already seen, games have often the option to play over a LAN. As previously mentioned, wireless networks are LANs, meaning that people can play together without having to be physically near each other. Isn't it more exciting to play with your family and friends instead of unknown people on the Internet and be able to make the whole game work much faster? Actually, you can even ask your friends to bring their own computers in and join a thrilling 'LAN party'!
With wireless networking you can easily connect any games you wish to play to the Internet, and start playing online. Playing online with a wirelessly connected to Xbox or PlayStation 2 is definitely simpler than having to use your modem for connection all the time.
Always On
What made the spread of broadband possible was that it let Internet connections be constantly on, eliminating the need of dialing in all the time. With wireless networking, network connections are always on, so that every time you wish, any of your computers is able to connect to the Internet!
Regardless of where you take your laptops to within your home, they will have instant access! Moreover, wireless networks offer you the convenience of eliminating usernames and password systems, as they operate without logging in. Talk about convenience!
No More Wires
Being able to eliminate wires from running all over your house is probably the biggest reason why you should turn your network to wireless. Believe me, you will be so pleased when you get rid of problematic, costly, ugly and unsafe wires.
Although the average Ethernet wire doesn't cost much, once you've bought the necessary quantity to do what you need to do, but getting everything you need for a wired LAN it adds up quickly. Plus, whenever you wish to have wires running between rooms or floors, you are forced to have holes in the walls, which might not even possible if the house is not yours.
Many people living in rented apartments have to limit their network to a particular room until they finally decided to switch to wireless allowing them to even take their computers outside, if they wish to!
Using wireless networks also enables you to have more safety, as there is no danger of tripping over uncovered wires. Furthermore, if you are moving, you do not have to pack all the wires up and re-connect them again.
Finally, with wireless networks there's no need for you to check every single wire if your Internet connection doesn't work.
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Feasibility study
Needs Analysis
A needs analysis should be the first undertaking of a feasibility study as it clearly defines
the project outline and the clients requirements. Once these questions have been
answered the person/s undertaking the feasibility study will have outlined the project
needs definition. The following questions need to be asked to define the project needs
definition: What is the end deliverable? What purpose will it serve? What are the
environmental effects? What are the rules and regulations? What standards will we be
measured against? What are the quality requirements? What is the minimal quality
requirements allowed? What sustainability can we expect? What carry over work can we
expect? What are the penalty clauses? How much do we need to outsource? How much
do we need to insource?
Economic feasibility study
The new system will involve new technology and instruments. The cost of setting up one
wireless router or wireless access point would approximately cost to about three thousand
to four thousand. The company should get a branded router. The training cost and
maintenance can also include.
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This involves questions such as whether the firm can afford to build the system, whether
its benefits should substantially exceed its costs, and whether the project has higher
priority and profits than other projects that might use the same resources. This also
includes whether the project is in the condition to fulfill all the eligibility criteria and the
responsibility of both sides in case there are two parties involved in performing any
project.
Technical feasibility study
The new wi-fi network system is supported to all the LAN ,WAN ,MAN,and Internet,
Interanet network. Wireless network require wireless router or wireless accsess point the
quantity of the product is depend upon according to the no of system and the area covered
by wireless .since a lot of new tehnology is added in the system . This is same as LAN
network so employe have not need to tranning . and the maintinance of this system is
very less. Four or five system have required one wireless access point or router and this is
cover 200 sq. meter area. But if there are not any concreet wall. Because this type of
partation always week the signal so the range is not good.
Organizational Feasibility study
The old system required a lot of cables. This system is used for remove the cable wire
complixity in the network. This is better for laptops because laptop is movable and if this
is connect via cable so it is to difficult to move laptop one place to another place but wi-fi
network give facility to connect any where in the range. and there is not need of cable.
So the daily cabling plug in and plug out problem is solve.
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Wi-Fi
A wireless network uses radio waves, just like cell phones, televisions and radios do. In fact, communication across a wireless network is a lot like two-way radio communication. Here's what happens:
1. A computer's wireless adapter translates data into a radio signal and transmits it using an antenna.
2. A wireless router receives the signal and decodes it. It sends the information to the Internet using a physical, wired Ethernet connection.
The process also works in reverse, with the router receiving information from the Internet, translating it into a radio signal and sending it to the computer's wireless adapter.
The radios used for Wi-Fi communication are very similar to the radios used for walkie-talkies, cell phones and other devices. They can transmit and receive radio waves, and they can convert 1’s and 0’s into radio waves and convert the radio waves back into 1s and 0s. But Wi-Fi radios have a few notable differences from other radios:
They transmit at frequencies of 2.4 GHz or 5GHz. This frequency is considerably higher than the frequencies used for cell phones, walkie-talkies and televisions. The higher frequency allows the signal to carry more data.
They use 802.11 networking standards, which come in several flavors: o 802.11b was the first version to reach the marketplace. It's the slowest and
least expensive standard, and it's becoming less common as faster standards become less expensive. 802.11b transmits in the 2.4 GHz frequency band of the radio spectrum. It can handle up to 11 megabits of data per second, and it uses complimentary code keying (CCK) coding.
o 802.11g also transmits at 2.4 GHz, but it's a lot faster than 802.11b -- it can handle up to 54 megabits of data per second. 802.11g is faster because it uses orthogonal frequency-division multiplexing (OFDM), a more efficient coding technique.
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o 802.11a transmits at 5GHz and can move up to 54 megabits of data per second. It also and uses OFDM coding. Newer standards, like 802.11n, can be even faster than 802.11g. However, the 802.11n standard isn't yet final.
Wi-Fi radios can transmit on any of three frequency bands. Or, they can "frequency hop" rapidly between the different bands. Frequency hopping helps reduce interference and lets multiple devices use the same wireless connection simultaneously.
As long as they all have wireless adapters, several devices can use one router to connect to the Internet. This connection is convenient and virtually invisible, and it's fairly reliable. If the router fails or if too many people try to use high-bandwidth applications at the same time, however, users can experience interference or lose their connections.
Meaning of the term 'Wi-Fi'
Despite the similarity between the terms 'Wi-Fi' and 'Hi-Fi', statements reportedly made by Phil Belanger of the Wi-Fi Alliance contradict the popular conclusion that 'Wi-Fi' stands for 'Wireless Fidelity.'According to Mr. Belanger, the Interbrand Corporation developed the brand 'Wi-Fi' for the Wi-Fi Alliance to use to describe WLAN products that are based on the IEEE 802.11 standards. In Mr. Belanger's words, "Wi-Fi and the yin yang style logo were invented by Interbrand. We [the founding members of the Wireless Ethernet Compatibility Alliance, now called the Wi-Fi Alliance] hired Interbrand to come up with the name and logo that we could use for our interoperability seal and marketing efforts. We needed something that was a little catchier than 'IEEE 802.11b Direct Sequence'."
One possibility for the origin of the actual term is a simplified spelling of "Wi-Phy" or "Wireless Physical Network Layer".
The Wi-Fi Alliance themselves invoked the term 'Wireless Fidelity' with the marketing of a tag line, "The Standard for Wireless Fidelity," but later removed the tag from their marketing. The Wi-Fi Alliance now seems to discourage the propagation of the notion that 'Wi-Fi' stands for 'Wireless Fidelity', but it has been referred to as such by the Wi-Fi Alliance in White Papers currently held in their knowledge base:
"... a promising market for wireless fidelity (Wi-Fi) network equipment."
"A Short History of WLANs... The association created the Wi-Fi (Wireless Fidelity) logo to indicate that a product had been certified for interoperability."
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Technical information
Wi-Fi networks use radio technologies called IEEE 802.11
Wi-Fi technology has gone through several generations since its inception in
1997.
Wi-Fi is supported to different extents under Microsoft Windows, Apple Mac OS
and various open source Unix-like systems.
USES OF WI-FI
Wi-Fi at home
Home Wi-Fi clients come in many shapes and sizes, from stationary PCs to digital cameras. The trend today is to incorporate wireless into every electronic where mobility is desired.
Wi-Fi devices in home or consumer-type environments connect in the following ways:
Via a broadband Internet connection into a single router which can serve both wired and wireless clients
Ad-hoc mode for client to client connections Built into non-computer devices to enable wireless connectivity to other devices
or the Internet
Wi-Fi in Business
Business and industrial Wi-Fi has taken off, with the trends in implementation varying greatly over the years. Current technology trends in the corporate wireless world are:
Dramatically increasing the number of Wi-Fi Access Points in an environment, in order to provide redundancy,support fast roaming and increasing overall network capacity by using more channels and/or creating smaller cells
Designing for wireless voice applications (VoWLAN or WVOIP) Moving toward 'thin' Access Points, with more of the network intelligence housed
in a centralized network appliance; relegating individual Access Points to be simply 'dumb' radios
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Outdoor applications utilizing true mesh topologies A proactive, self-managed network that functions as a security gateway, firewall,
DHCP server, intrusion detection system, and a myriad of other features not previously considered relevant to a wireless network.
Advantages of Wi-Fi
Allows LANs to be deployed without cabling for client devices, typically
reducing the costs of network deployment and expansion. Spaces where cables
cannot be run, such as outdoor areas and historical buildings, can host wireless
LANs.
Built into most modern laptops, getting a laptop without a built in WiFi has
become an exception.
Wi-Fi chipset pricing continues to come down, making Wi-Fi a very economical
networking option and driving inclusion of Wi-Fi in an ever-widening array of
devices.
Wi-Fi products are widely available in the market. Different competitive brands
of access points and client network interfaces are inter-operable at a basic level of
service. Products designated as Wi-Fi CERTIFIED by the Wi-Fi Alliance are
backwards inter-operable.
Wi-Fi is a global set of standards. Unlike cellular carriers, the same Wi-Fi client
works in different countries around the world.
Widely available in more than 250,000 public hot spots and tens of millions of
homes and corporate and university campuses worldwide.
As of 2007, WPA is not easily cracked if strong passwords are used and WPA2
encryption has no known weaknesses.
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New protocols for Quality of Service (WMM) and power saving mechanisms
(WMM Power Save) make Wi-Fi even more suitable for latency-sensitive
applications (such as voice and video) and small Form-Factor
Disadvantages of Wi-Fi
Spectrum assignments and operational limitations are not consistent worldwide;
most of Europe allows for an additional 2 channels beyond those permitted in the
US (1-13 vs 1-11); Japan has one more on top of that (1-14) - and some countries,
like Spain, prohibited use of the lower-numbered channels (note that Europe, as of
2007, is now essentially homogeneous in this respect). Furthermore some
countries, such as Italy, used to require a 'general authorization' for any Wi-Fi
used outside an operator's own premises, or require something akin to an operator
registration.
Equivalent isotropically radiated power (EIRP) in the EU is limited to 20 dBm
(0.1 W).
Power consumption is fairly high compared to some other low bandwidth
standards (Zigbee and Bluetooth), making battery life a concern.
The most common wireless encryption standard, Wired Equivalent Privacy or
WEP, has been shown to be easily breakable even when correctly configured. Wi-
Fi Protected Access (WPA and WPA2) which began shipping in 2003 aims to
solve this problem and is now available on most products.
Wi-Fi Access Points typically default to an open (encryption-free) mode. Novice
users benefit from a zero configuration device that works out of the box but
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without security enabled providing open wireless access to their LAN. To turn
security on requires the user to configure the device, usually via a software GUI.
Many 2.4 GHz 802.11b and 802.11g Access points default to the same channel on
initial start up, contributing to congestion on certain channels. To change the
channel of operation for an access point requires the user to configure the device.
Wi-Fi networks have limited range. A typical Wi-Fi home router using 802.11b or
802.11g with a stock antenna might have a range of 45 m (150 ft) indoors and 90
m (300 ft) outdoors. Range also varies with frequency band. Wi-Fi in the 2.4 GHz
frequency block has slightly better range than Wi-Fi in the 5 GHz frequency
block. Outdoor range with improved antennas can be several kilometres or more
with line-of-sight.
Wi-Fi pollution, of an excessive number of an access point with other access
points in the area, especially on the same or neighboring channel, can prevent
access and interfere with the use of other access points by others caused by
overlapping channels in the 802.11g/b spectrum as well as with decreased signal-
to-noise ratio (SNR) between access points. This can be a problem in high-density
areas such as large apartment complexes or office buildings with many Wi-Fi
access points. Additionally, other devices use the 2.4 GHz band: microwave
ovens, cordless phones, baby monitors, security cameras, and Bluetooth devices
can cause significant additional interference.
It is also an issue when municipalities[3] or other large entities such as universities
seek to provide large area coverage. Everyone is considered equal for the base
standard without 802.11e/WMM when they use the band. This openness is also
important to the success and widespread use of 2.4 GHz Wi-Fi, but makes it
unsuitable for "must have" public service functions or where reliability is
required. Users sometimes suffer network "frustrations" or a total network
breakdown if gaming because a neighbour microwaves some pop corn.
Interoperability issues between brands or proprietary deviations from the standard
can disrupt connections or lower throughput speeds on other user's devices that
are within range. And, Wi-Fi devices do not presently pick channels to avoid
interference.
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Wi-Fi networks that are open (unencrypted) can be monitored and used to read
and copy data (including personal information) transmitted over the network
unless another security method is used to secure the data like a VPN or a secure
web page.
Manufacturers
There are many vendors’ now manufacturing and selling 802.11n products. They include:
Acer Airgo Networks Apple Asus Atheros Broadcom Buffalo Technology Dell Intel Linksys Netgear Pronet U.S. Robotics
Embedded systems
Wi-Fi availability in the home is on the increase. This extension of the Internet into the home space will increasingly be used for remote monitoring. Examples of remote monitoring include security systems and tele-medicine. In all these kinds of implementation, if the Wi-Fi provision is provided using a system running one of operating systems mentioned above, then it becomes unfeasible due to weight, power consumption and cost issues.
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Increasingly in the last few years (particularly as of early 2007), embedded Wi-Fi modules have become available which come with a real-time operating system and provide a simple means of wireless enabling any device which has and communicates via a serial port.
This allows simple monitoring devices, for example a portable ecg monitor hooked up to a patient in the home, to be created. This Wi-Fi enabled device effectively becomes part of the internet cloud and can communicate with any other node on the internet. The data collected can hop via the home's Wi-Fi access point to anywhere on the internet.
These Wi-Fi modules are designed so that minimal Wi-Fi knowledge is required by designers to wireless enable their product.
DIFFERENT TYPESOF
WIRELESS NETWORK
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ANDTHEIR LIMITATIONS
Wireless Router Network Diagram
Common layout for Wi-Fi-based home networksThis diagram illustrates use of a Wi-Fi wireless network router as the central device of a home network. See below for a detailed description of this layout.
Wireless Home Network Diagram Featuring Wi-Fi Router
Key Considerations - All devices connecting to a wireless router must possess a working network adapter. As illustrated in the diagram, connecting to the router a broadband modem (that has one or more built-in adapters) enables sharing of a high-speed Internet connection.
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Wireless routers technically allow dozens of computers to connect over Wi-Fi links. Nearly any residential wireless router will have no trouble supporting the number of wireless devices found in typical homes. However, if all Wi-Fi computers attempt to use the network at the same time, slowdowns in performance should be expected. Many (but not all) wireless network routers also allow up to four wired devices to be connected via Ethernet cable. When first installing this kind of home network, one computer should be cabled to the wireless router temporarily to allow initial configuration of the wireless features. Employing Ethernet connections after that is optional. Using permanent Ethernet connections make sense when the computer, printer or other device lacks Wi-Fi capability or cannot receive an adequate wireless radio signal from the router.
Optional Components - Networking the router for Internet access, printers, game consoles and other entertainment devices is not required for the rest of the home network to function. Simply omit any of these components shown that do not exist in your layout.
Limitations - The Wi-Fi portion of the network will function only to the limit of the wireless router's range. The range of Wi-Fi equipment varies depending on many factors including layout of the home and any radio interference that may be present. If the wireless router does not support enough Ethernet connections for you needs, add a secondary device like a network switch to expand the wired portion of the layout.
Ethernet Router Network Diagram
Common layout for Ethernet-based home networks
This diagram illustrates use of a wired network router as the central device of a home network. See below for a detailed description of this layout.
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Wired Home Network Diagram Featuring Ethernet Router
Key Considerations - Many (but not all) wired network routers allow up to four devices to be connected via Ethernet cable.
All devices connecting to an Ethernet router must possess a working Ethernet network adapter.
Optional Components - Networking the router for Internet access, printers, game consoles and other entertainment devices is not required for the rest of the home network to function. Simply omit any of these components shown that do not exist in your layout.
Limitations - If the Ethernet router does not support enough Ethernet connections, add a secondary device like a network switch to expand the layout
Hybrid Ethernet Router / Wireless Access Point Network Diagram
Common layout for hybrid home networksThis diagram illustrates use of a hybrid wired network router / wireless access point home network. See below for a detailed description of this layout.
Hybrid Home Network Diagram Featuring Wired Router and Wireless Access Point
Key Considerations - Most (but not all) wired network routers allow up to four devices to be connected via Ethernet cable. A wireless access point consumes one of these available ports, but it then enables many (dozens of) Wi-Fi devices to join the network.
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Nearly any home network wireless access point will have no issue managing to support the number of wireless devices there. However, if all Wi-Fi computers attempt to use the network at the same time, performance slowdowns can result.
All devices connecting to an Ethernet router must possess a working Ethernet network adapter. All devices connecting a wireless access point must possess a working Wi-Fi network adapter.
Optional Components - Networking of Internet access, printers, game consoles and other entertainment devices is not required for either the router or access point to function. Simply omit any of these components shown that do not exist in your layout.
You can choose which devices to connect to the router and which to the wireless access point. Additional network adapters may be needed to convert some Ethernet devices, particularly printers and game consoles, to work wirelessly.
Limitations - The Wi-Fi portion of the network will function only to the limit of the wireless access point's range. The range of Wi-Fi equipment varies depending on many factors including layout of the home and any radio interference that may be present.
If the wireless router does not support enough Ethernet connections, add a secondary device like a network switch to expand the wired portion of the layout.
Direct Connection Network Diagram
Common layout for simple Ethernet home networksThis diagram illustrates direct connection without a router or other central device on the home network. See below for a detailed description of this layout.
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Wired Home Network Diagram Featuring Direct Connection
Key Considerations - Direct connection can be achieved with several different types of cabling. Ethernet cabling is the most common, but even simpler (slower) alternatives exist including RS-232 serial cable, and parallel cable. Direct Connection is common for game consoles to support two-player network gaming.
Optional Components - Connecting to the Internet requires that one computer possess two network adapters - one to support the Internet connection and one to support the second computer. Additionally, Internet connection sharing software must be installed to allow the second computer Internet access. If Internet connectivity is not necessary, these things can be omitted from this layout.
Limitations - Direct connection works only for a single pair of computers / devices. Additional devices cannot join such a network, although other pairs can be connected separately as shown above.
Ad Hoc Wireless Network Diagram
Common layout for Wi-Fi-based home networksThis diagram illustrates use of a so-called ad hoc wireless setup in a home network. See below for a detailed description of this layout.
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Wireless Home Network Diagram Featuring Ad Hoc Wi-Fi Connections
Key Considerations - Using ad hoc Wi-Fi mode eliminates the need for a network router or access point in a wireless home network. With ad hoc wireless, you can network computers together as needed without needing to be in reach of one central location. Most people use ad hoc Wi-Fi only in temporary situations to avoid potential security issues.
Optional Components - Networking an ad hoc layout for Internet access, printers, or game consoles and other entertainment devices is not required for the rest of the home network to function. Simply omit any of these components shown that do not exist in your layout.
Limitations - All devices connecting via ad hoc wireless must possess a working Wi-Fi network adapter. These adapters must be configured for "ad hoc" mode instead of the more typical "infrastructure" mode.
Because of their more flexible design, ad hoc Wi-Fi networks are also more difficult to keep secures than those using central wireless routers / access points.
Ad hoc Wi-Fi networks support a maximum of 11 Mbps bandwidth, while other Wi-Fi networks may support 54 Mbps or higher.
Ethernet Hub/Switch Network Diagram
Common layout for Ethernet-based home networksThis diagram illustrates use of an Ethernet hub or switch on a home network. See below for a detailed description of this layout.
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Wired Home Network Diagram Featuring Ethernet Hub or Switch
Key Considerations - Ethernet hubs and switches allow multiple wired computers to network with each other. Most (but not all) Ethernet hubs and switches support up to four connections.
Optional Components - Networking of Internet access, printers, or game consoles and other entertainment devices is not required for the rest of this home network layout to function. Simply omit any of these components shown that do not exist in your design.
Additional hubs and switches can be incorporated to the basic layout shown. Connecting hubs and/or switches to each other expands the total number of computers the network can support up to several dozen.
Limitations - All computers connecting to a hub or switch must possess a working Ethernet network adapter.
As shown, unlike a network router, Ethernet hubs and switches cannot interface directly to an Internet connection. Instead, one computer must be designated as controlling the Internet connection and all other computers access the Internet through it. Internet connection sharing software can be installed on each computer for this purpose.
Phone line Home Network Diagram
Layout for HPNA-based phone line home networks
This diagram illustrates use of Home Phoneline Networking Alliance equipment to build a home network. See below for a detailed description of this layout.
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Phone line Home Network Diagram Featuring HPNA Gateway / Router
Key Considerations - Phone line networks utilize the ordinary telephone wiring of a residence to carry home network communications. As with Ethernet or Wi-Fi networks, phone line networks require each device to have a compatible phoneline network adapter installed. These adapters are connected by ordinary phone wires (or sometimes CAT5 Ethernet cable) to telephone wall outlets.
When connecting multiple computers with phoneline networking, one central computer "gateway" must be established. The gateway represents the network's primary device for connecting to the Internet. A few models of home network routers (sometimes called "residential gateways") support phoneline networking today. Otherwise, you must designate one computer as the gateway and install two network adapters on this computer to enable it for gateway functions. Depending on the type of primary device chosen, hybrid networks with a combination of phoneline, Ethernet or Wi-Fi devices can be created.
The Home Phoneline Networking Alliance (HomePNA) develops technology standards that compatible phoneline equipment must support.
Optional Components - As mentioned above, a network router is optional when building a phoneline home network. Phoneline networking also works regardless of whether the residence is subscribed either to basic local telephone service or to DSL Internet service.
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Limitations - HomePNA phone line networking has proven much less popular than Wi-Fi or Ethernet alternatives. Phone line networking products will generally be more difficult to find, and there will be fewer choices of models for this reason.
All phone line network equipment must be connected to the same electrical circuit within the residence. Specifically, residences that have two phone lines installed must choose one or the other line to connect all devices.
The range of an HomePNA (version 2.0) phone line network is about 1000 feet (300 m). The maximum bandwidth of an HomePNA 2.0 network is 10 Mbps, while an HomePNA 3.0 network supports more than 100 Mbps. The speed of phone line networking can suffer depending on the quality of phone cables installed in the residence.
Powerline Home Network Diagram
Layout for HomePlug powerline home networksThis diagram illustrates use of HomePlug equipment to build a powerline home network.
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Powerline Home Network Diagram Featuring Powerline Router
Key Considerations - Powerline networks utilize the ordinary electrical circuitry of a residence to carry home network communications. Available powerline equipment includes network routers, network bridges and other adapters. To connect to a powerline network, one end of the adapter plugs into a standard electric wall outlet while the other connects to a device's network port (usually Ethernet or USB). All connected devices share the same communication circuit. The HomePlug Powerline Alliance develops technology standards supported by compatible powerline equipment.
Optional Components - Not all devices on the home network must be connected to a powerline router; hybrid networks with Ethernet or Wi-Fi devices can be joined with the powerline network. For example, a Wi-Fi powerline bridge can optionally be plugged into a wall outlet, enabling wireless devices to connect to it and in turn to the rest of the powerline network.
Limitations - HomePlug phoneline networking remains much less popular than Wi-Fi or Ethernet alternatives. Powerline networking products will generally be more difficult to find with fewer choices of models for this reason. Powerline networks generally do not work as reliably if devices plug into power strips or extensions cords. Connect directly to the wall outlets for best results. In homes with multiple circuits installed, all devices must connect to the same one circuit to communicate with each other. The maximum bandwidth of a HomePlug (version 1.0) powerline network is 14 Mbps; while the newer HomePlug AV standard supports more than 100 Mbps. Poor quality electrical wiring as found in older homes can degrade the performance of a powerline network.
How Wi-Fi Works
If you've been in an airport, coffee shop, library or hotel recently, chances are you've been right in the middle of a wireless network. Many people also use wireless
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networking, also called WiFi or 802.11 networking, to connect their computers at home, and an increasing number of cities use the technology to provide free or low-cost Internet access to residents. In the near future, wireless networking may become so widespread that you can access the Internet just about anywhere at any time, without using wires.
One wireless router can allow multiple devices to connect to the Internet.
WiFi has a lot of advantages. Wireless networks are easy to set up and inexpensive. They're also unobtrusive -- unless you're on the lookout for a place to use your laptop, you may not even notice when you're in a hotspot. In this article, we'll look at the technology that allows information to travel over the air. We'll also review what it takes to create a wireless network in your home.
Before You Buy a Wireless Internet Router
All wireless Internet routers might appear very much alike at first glance. In fact, many different wireless router models exist each with its own unique set of attributes. Use the
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checklist below to help decide which brand of wireless network router could work best for you.
Uncover Discounts and Generally Low Prices
All other things being equal, many consumers will choose the product that costs the least. Manufacturers will often offer rebates or other discounts from the full retail price of their wireless routers. You may be getting an older product instead of the latest and greatest, but with network gear, that's not necessarily a bad thing. Shop around and you're likely to land a good value for your money.
Research the Popular Models
An old adage says: "There is safety in numbers." Odds are, if many people are buying a particular product, it's serving a useful need. Top selling network gear tends to be current generation technology but not cutting edge. If you tend to play it conservative and run with the pack, check sales rankings at online retailers to start building your wireless Internet router short list.
Consider Terms of Warranty
Wireless Internet router manufacturers always provide a warranty package together with their equipment. The length and terms of these warranties vary widely. A better warranty may indicate a manufacturer more committed to support their products, while a lesser warranty could indicate a somewhat lesser standard of product quality or reliability. Always consider wireless router warranties when making your purchase decision.
Ignore (Most of) the Success and Horror Stories Told by Others
Countless consumers post opinions of their particular wireless Internet router to blogs, message boards, retailer Web sites and elsewhere online. For most brands of routers, a confusing mix of positive and negative anecdotes awaits you. Due to the complexity of home networking today, any given brand of wireless router that performs flawlessly in one person's home network could fail miserably in yours. Bottom line: Don't let someone else's experience, good or bad; sway your decision too much.
Try Brand Matching Your Network Adapters
Consider purchasing a wireless Internet router of the same brand as at least one of your wireless network adapters. The benefit is a small one, but sometimes vendors will optimize communication protocols of their own equipment; you may see slightly higher performance. Vendors may also more thoroughly test compatibility with their own equipment. If you don't own any adapters (or newer laptops with built-in wireless), consider purchasing all of your WiFi gear together from the same manufacturer.
Find a Good Fit in Size and Style
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In many households, wireless Internet routers are installed in a visible central area of the residence. Purchasing a stylish router can make this an attractive addition to the decor that you will be proud to show family and friends. Routers vary in both size and shape. If you plan to install the router in a confined space, ensure you pick one with a suitable form factor. Small business owners and others interested in portability may likewise consider the class of "travel router" products.
Satisfy Your Need for Speed
You may be tempted to ignore all else and simply snap up the wireless Internet router with the highest speed rating (in Mbps). In fact, these speed ratings may be the least important of all factors listed here. Consider that the actual performance you will achieve in practice typically averages much, much lower than the maximum rating shown on the package. Furthermore, high-speed routers cannot directly speed up your Internet connection that is usually the real bottleneck on a home network.
Networking with a Router
Using a router on broadband and/or wireless home networks
A network router is a small electronic device that allows you build a home network simply. The home router serves as the core or "centerpiece" of the network to which computers, printers and other devices can be connected. Networking with a router helps you to (for example):
share files between computers share an Internet connection between computers share a printer connect your game console or other home entertainment equipment to the Internet Routers are not necessarily required to build a network. For example, you can
connect two computers directly to each other with just a cable (or without wires in some cases). Home routers offer convenience and easier maintenance as your network grows.
Related - Connecting Two Home Computers
Choosing a Network Router
You can choose from among several different types of home network router products.
The two most common types in popular usage are the 802.11b and 802.11g WiFi models. 802.11g is the newer technology, but 802.11b routers often can do the job for an even lower cost.
Installing a Network Router
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Network routers receive their power from an ordinary home electrical socket. When powered on, lights (LEDs) signify the unit is operating.
Network routers must be carefully configured when they are first installed. Like computers and other devices on the home network, routers must be set up with IP addresses. Routers also offer optional (but strongly recommended) security features.
Routers contain built-in software to enable setup. You access this software through your Web browser on any computer connected to the router.
How to Build a Wireless Home Network
Introduction to wireless computer networking
This tutorial will guide you through the process of planning, building, and testing a wireless home network. Although mainstream wireless networking has made amazing strides in the past few years, wireless technology and terminology remains a bit difficult for most of us to comprehend. This same guide will help small business networkers, too!
Build a Wireless LAN, Step by Step
You can build any typical wireless home network, a wireless LAN (WLAN), using this simple three-step approach:
1. Identify the WLAN design that's best for your situation2. Choose good wireless gear3. Install gear and test the configured WLAN
In subsequent pages, I break down each of these steps in more detail.
Ready to Go Wireless?
This article assumes you've already made an informed decision to go wireless rather than build a traditional cabled network. Though prices have dropped dramatically from a few years ago, when wireless gear was quite expensive, wireless networks still aren't for everyone (yet). Unsure that wireless will really meet your needs? Use the following supplementary article to help you choose wisely:
Types of Wireless Equipment
The five types of equipment found in wireless home networks are:
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Wireless network adapters Wireless access points Wireless routers Add-on wireless antennas Wireless signal boosters
Wireless Routers
Linksys WRT54G Wireless Broadband Router
The centerpiece product of many home computer networks is a wireless router. These routers support all home computers configured with wireless network adapters (see below). They also contain a network switch to allow some computers to be connected with Ethernet cables. Wireless routers allow cable modem and DSL Internet connections to be shared. Additionally, many wireless router products include a built-in firewall that protects the home network from intruders. Illustrated above is the Linksys WRT54G (compare prices). This is a popular wireless router product based on the 802.11g Wi-Fi network standard. Wireless routers are small box-like devices generally less than 12 inches (0.3 m) in length, with LED lights on the front and with connection ports on the sides or back. Some wireless routers like the WRT54G feature external antennas that protrude from the top of the device; others contain built-in antennas. Wireless router products differ in the network protocols they support (802.11g, 802.11a, 802.11b or a combination), in the number of wired device connections they support, in the security options they support, and in many other smaller ways. Generally only one wireless router is required to network an entire household.
Wireless Access Points
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Linksys WAP54G Wireless Access Point
A wireless access point (sometimes called an "AP" or "WAP") serves to join or "bridge" wireless clients to a wired Ethernet network. Access points centralize all WiFi clients on a local network in so-called "infrastructure" mode. An access point in turn may connect to another access point, or to a wired Ethernet router.
Wireless access points are commonly used in large office buildings to create one wireless local area network (WLAN) that spans a large area. Each access point typically supports up to 255 client computers. By connecting access points to each other, local networks having thousands of access points can be created. Client computers may move or "roam" between each of these access points as needed.
In home networking, wireless access points can be used to extend an existing home network based on a wired broadband router. The access point connects to the broadband router, allowing wireless clients to join the home network without needing to rewire or re-configure the Ethernet connections.
As illustrated by the Linksys WAP54G (compare prices) shown above, wireless access points appear physically similar to wireless routers. Wireless routers actually contain a wireless access point as part of their overall package. Like wireless routers, access points are available with support for 802.11a, 802.11b, 802.11g or combinations.
Wireless Network Adapters
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Linksys WPC54G Wireless Network Adapter
A wireless network adapter allows a computing device to join a wireless LAN. Wireless network adapters contain a built-in radio transmitter and receiver. Each adapter supports one or more of the 802.11a, 802.11b, or 802.11g Wi-Fi standards.
Wireless network adapters also exist in several different form factors. Traditional PCI wireless adapters are add-in cards designed for installation inside a desktop computer having a PCI bus. USB wireless adapters connect to the external USB port of a computer. Finally, so-called PC Card or PCMCIA wireless adapters insert into a narrow open bay on a notebook computer.
One example of a PC Card wireless adapter, the Linksys WPC54G (compare prices) is shown above.
Each type of wireless network adapter is small, generally less than 6 inches (0.15 m) long. Each provides equivalent wireless capability according to the Wi-Fi standard it supports.
Some notebook computers are now manufactured with bulit-in wireless networking. Small chips inside the computer provide the equivalent functions of a network adapter. These computers obviously do not require separate installation of a separate wireless network adapter.
Wireless Print Servers
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Linksys WPS54G Wireless Print Server
A wireless print server allows one or two printers to be conveniently shared across a WiFi network. Wireless print servers for home networks generally are available in both 802.11b and 802.11g varieties.
Wireless print servers offer the following advantages:
Allows printers to be conveniently located anywhere within wireless network range, not tied to the location of computers
Does not require a computer be always turned on in order to print Does not require a computer to manage all print jobs, that can bog down its
performance Allows administrators to change computer names and other settings without having to
re-configure the network printing settings.
A wireless print server must be connected to printers by a network cable, normally USB 1.1 or USB 2.0. The print server itself can connect to a wireless router over WiFi, or it can be joined using an Ethernet cable.
Most print server products include setup software on a CD-ROM that must be installed on one computer to complete the initial configuration of the device. As with network adapters, wireless print servers must be configured with the correct network name (SSID) and encryption settings. Additionally, a wireless print server requires client software be installed on each computer needing to use a printer.
The Linksys WPS54G (compare prices) 802.11g USB wireless print server is shown. Print servers are very compact devices that include a built-in wireless antenna and LED lights to indicate status.
Wireless Game Adapters
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Linksys WGA54G Wireless Game Adapter
A wireless game adapter connects a video game console to a Wi-Fi home network to enable Internet or head-to-head LAN gaming. Wireless game adapters for home networks are available in both 802.11b and 802.11g varieties. An example of an 802.11g wireless game adapter appears above, the Linksys WGA54G Wireless game adapters can be connected either to a wireless router using an Ethernet cable (for best reliability and performance) or over Wi-Fi (for greater reach and convenience). Wireless game adapter products include setup software on a CD-ROM that must be installed on one computer to complete initial configuration of the device. As with generic network adapters, wireless game adapters must be configured with the correct network name (SSID) and encryption settings.
Wireless Range Extender
Linksys WRE54G Wireless Range Expander
A wireless range extender increases the distance over which a WLAN signal can spread, overcoming obstacles and enhancing overall network signal quality. Several different forms of wireless range extenders are available. These products are sometimes called "range expanders" or "signal boosters.
A wireless range extender works as a relay or network repeater, picking up and reflecting WiFi signals from a network's base router or access point. The network performance of devices connected through a range extender will generally be lower than if they were connected directly to the primary base station.
A wireless range extender connects wirelessly to a WiFi router or access point. However, due to the nature of this technology, most wireless range extenders work only with a limited set of other equipment. Check the manufacturer's specifications carefully for compatibility information.
Wireless Internet Video Cameras
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Linksys WVC54G Wireless Internet Video Camera
A wireless Internet video camera allows video (and sometimes audio) data to be captured and transmitted across a WiFi computer network. Wireless Internet video cameras are available in both 802.11b and 802.11g varieties. The Linksys WVC54G 802.11g wireless camera is shown above.
Wireless Internet video cameras work by serving up data streams to any computer that connects to them. Cameras like the one above contain a built in Web server. Computers connect to the camera using either a standard Web browser or through a special client user interface provided on CD-ROM with the product. With proper security information, video streams from these cameras can also be viewed across the Internet from authorized computers.
Wi-Fi Internet video cameras can be connected to a wireless router using either an Ethernet cable or wirelessly. These products include setup software on a CD-ROM that must be installed on one computer to complete initial Wi-Fi configuration of the device.
Features that distinguish different wireless Internet video cameras from each other include:
resolution of the captured video images (for example, 320x240 pixel, 640x480 pixel, and other image sizes)
motion sensors, and the ability to send email alerts when new activity is detected and captured
ability to timestamp images built-in microphones and/or jacks for external microphones, for audio support types of WiFi security supported, such as WEP or WAP
Making the Decision to go Wireless
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To share files between computers To share printers To share an Internet connection
Types of Networks used in a Home
Hard Wired
Wireless
Wireless Standards
802.11ao Speed 54Mbso Frequency used is 5 gigahertz (Ghz).
802.11bo Speed 11Mbso Frequency used is 2.4 gigahertz (Ghz).
802.11go Speed 54Mbso Frequency used is 2.4 gigahertz (Ghz).
802.11no Speed 200Mbs (Typ), 540Mps (max)o Frequency used is 2.4 gigahertz (Ghz).o Range indoors is 50m
New and Future Technology
Multiple-Input Multiple-Output (MIMO) Allows present technology to achieve greater throughput with the present
standards, In the future 802.11n may be the new standard for wireless local-area networks
Throughput may reach 540 Mbs 10 times faster than 802.11a or 802.11g A better operating distance May include MIMO technology
Wireless Router Features
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Contain a wireless access point Allows wireless devices to connect
May use MIMO technology Increases throughput
Contain a hardware firewall Stops inbound data unless you request it
Have setup for Wireless security Keeps strangers from accessing LAN through the wireless access point
Some Wireless Router and Wireless Adapter Brands
Linksys D-Link PRONET AirLink Belkin Netgear
Firewalls
You should have a fire wall on all your computers that have access to the internet Two types of fire walls
Hardware fire wall Used to stop incoming data that is not requested by your computer
Software firewalls Zone Alarm is used to keep your computer from sending or
receiving information without your permission.
Wireless security
In the Router:
Change the default Service Set Identifier (SSID) Disable the SSID broadcast Change the User Name and Passwords on the wireless router Set up the wireless encryption Setup the MAC Filter Change the routers local IP address
Wireless Security – Encryption Types
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Wired Equivalent Privacy ( WEP ) The oldest encryption method Uses a 64-bit or more secure 128 bit key
Wi-Fi Protected Access ( WPA ) Newer encryption method that uses 256-bit key
Wi-Fi Protected Access 2 ( WPA2 ) Newest encryption method Backward compatible with WPA
Setting up your Wireless Router
Things you need to know Who is your ISP
What type of Internet connection are you using User name and password if required
Brand of router Default local IP address Default User Name Default Password
Demonstration on setting up wireless router
Use setup CD that came with router If you already have a router installed you should remove it first. The
installation software will try to determine the type of connection Or
Bring up browser and access router Inter routers local IP address in the URL Inter the default User Name and Password Setup router
Setting up the wireless adapter in the remote PC
You must know the SSID and encryption KEY for the network you wish to connect. We entered these in the router.
Types of wireless networks Infrastructure Ad-Hoc
For this demonstration we will be using an Infrastructure network
Description of the networks for your information
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Infrastructure network Wireless network centered about an access point Access point
Provides communication with the wired network Mediates wireless network traffic in the immediate neighborhood
Description of the networks for your information
Ad-Hoc Are point-to-point networks
May consist of two or more mobile computers A collection of computers which propagate the signals. (A
to B to C to A). May be simple point to point
Description of the networks
Ad-Hoc
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May be a more complex system with multiple entities
The type of wireless adapters
Will depend on your wireless PC For a desktop
PCI adapter USB adapter
For the laptop PC card ( PCMCIA card) USB adapter
Use an adapter that matches your router to get maximum throughputInstalling the wireless adapter
Use the installation instructions that come with your wireless adapter Using the correct sequence
Install hardware Use CD that comes with the hardware
Install the driver Install the software (utility program)
Connecting the wireless computer to the access point Have the remote computer scan for networks
Find SSID of your network and select it enter the encryption key that was used to set up the wireless part of
the router Confirm key if necessary
Click on connect You should be connected to the network
1- D-link DSL-G604T:
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Product Features:
Combined Wireless Router and ADSL Modem Solution Wirelessly Connect to the Internet With 802.11g Technology Network Security with Integrated Firewall Features Up to 150x Faster Than Dial-Up Modems
Product Description:
D-Link, an industry leader in networking, introduces the DSL-G604T, a Wireless ADSL router modem combining both an ADSL modem and 802.11g wireless router in one unit, bringing high-speed wireless Internet connection to a home or office.
The DSL-G604T uses ADSL (Asymmetric Digital Subscriber Line) technology for Internet connection speeds of up to 150x faster than dial-up, while using a standard phone line.
Using 802.11g wireless technology, Wi-Fi enabled computers and devices can wirelessly connect to the DSL-G604T and share a single incoming Internet connection. With four additional Ethernet LAN ports, you can connect your network Ethernet-enabled devices.
The router functionality on the DSL-G604T Wireless ADSL Router Modem includes support for VPN pass-through of multiple concurrent IPSec and PPTP tunnels, making it especially useful for telecommuters or users who need a more secure way to communicate and transmit information.
A simple configuration tool and a Web-based user interface allow you to easily modify settings to connect to your Internet Service Provider (ISP). This Web interface also provides traffic statistics, connection speed, and other detailed information.
The DSL-G604T Wireless ADSL Router Modem supports static IP, Dynamic IP, as well as PPPoE connections, and works with applications such as online gaming and VPN connections with no additional configuration. The DSL-G604T is easily upgradeable, making it future-proof for both end-users and service providers.
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Whether it’s for a home user who wants to share wireless high-speed Internet access or for a small office that needs Internet access for conducting essential business activities, the DSL-G604T Wireless ADSL Router Modem is the ideal all-in-one broadband solution.
SPESIFICATION:
DSL-G604T > Wireless G ADSL Router Modem
Specifications
Standards
• ANSI T1.413 issue 2
• ITU G.992.1 (G.dmt)
• ITU G.992.2 (G.lite)
• ITU G.994.1 (G.hs)
• IEEE 802.3
• IEEE 802.3u
• IEEE 802.11
• IEEE 802.11b
• IEEE 802.11g
Ports• RJ-11 Port for Connection to ADSL
• Four 10/100Mbps Ethernet LAN Ports for Connection to Ethernet-enabled devices
Device Management
• Telnet
• HTTP Web Management
• TFTP for Firmware Upgrade
DSL Data Rates
• DMT full rate downstream (up to 8Mbps)
• DMT full rate upstream (up to 640Kbps)
• G.lite ADSL downstream (up to 1.5Mbps)
• G.lite ADSL upstream (up to 512Kbps)
Software Features • Dynamic Learning (Up to 256 MAC Addresses)
DHCP • Server and Client
Routing Protocols Supported• TCP/UDP, ARP, RARP, ICMP, DHCP, DNS, RIPv1
(RFC 1058), RIP v2 (RFC1389), IGMP, PPPoE, IGMP, P2PP
VPN Pass Through
• L2TP
• PPTP
• IPSec
Wireless Signal Rates* With Automatic Fallback
• IEEE 802.11b: 11, 5.5, 2, and 1Mbps
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• IEEE 802.11g: 54, 48, 36, 24, 18, 12, 9, 6Mbps
Media Access Protocol • DSMA/CA with ACK
Wireless Security• WEP: 64/128/256-bit
• WPA (IEEE 802.1x + TKIP)
Wireless Frequency Range • 2400 ~ 2484.5Mhz ISM Band
Radio and Modulation Type• IEEE 802.11b: DQPSK, DBPSK, DSSS, and CCK
• IEEE 802.11g: BPSK, QPSK, 16QAM, 64QAM. OFDM
Channels• 11 Channels (US)
• 13 Channels (Europe and Japan)
LEDs
• Power
• Status
• WLAN
• ADSL Link/Act
• Ethernet Link/Act
• Ethernet 10/100M
Power• Output: 12V AC, 1.2A
• Max Power Consumption: 12W
Operating Temperature • 0º to 40ºC (32ºF to 104ºF)
Storage Temperature • -20º to 70ºC (-4ºF to 158ºF)
Certifications
• FCC Part 15 Class B
• FCC Part 68
• IEC 60950
• EN 60950
• CSA 950
• CE Mark
• UL 1950 3rd Ed
Dimensions • 7.07in x 5.59in x 1.18in
Weight • 0.8lbs
Warranty • 1 Year
Detailed View
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Product Diagram
2 - D-LINK DWL-G700AP:
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Product Features:
Up to 54Mbps WPA for Enhanced Wireless Security Quickly Add Wireless Access to Your Network Web-based Configuration and Management
Product Description:
D-Link, an industry leader in networking, introduces the new D-Link AirPlus™ G DWL-G700AP Access Point. With the ability to transfer files with a maximum wireless signal rate of up to 54Mbps*, the DWL-G700AP gives you high-speed wireless network access for your home or office.
The DWL-G700AP is Wi-Fi IEEE 802.11g compliant, meaning that it can connect and interoperate with other 802.11g compatible wireless client devices. The G700AP is also backwards compatible to 802.11b.
The D-Link DWL-G700AP Access Point has been verified and successfully passed through the Intel Wireless Verification Program, which tests the compatibility of various access point devices and wireless service providers with common configuration of notebooks built on Intel® Centrino™ mobile technology.
With its web-based setup wizard, the DWL-G700AP Access Point ensures that you will be up and running on a wireless network in just a matter of minutes. The DWL-G700AP also includes an embedded DHCP server that can automatically assign IP addresses to wireless network clients.
The DWL-G700AP Access Point features Wi-Fi Protected Access (WPA) and 64/128-bit WEP Encryption to provide an enhanced level of security for wireless data communications. The DWL-G700AP also includes additional security features to keep your wireless connection safe from unauthorized access.
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With easy-to-use Web-based management, the DWL-G700AP Access Point is the right choice for setting up your first wireless network or extending the range of an existing wireless network.
Maximum wireless signal rate derived from IEEE Standard 802.11g specifications. Actual data throughput will vary. Network conditions and environmental factors, including volume of network traffic, building materials and construction, and network overhead, lower actual data throughput rate. Environmental factors will adversely affect wireless signal range. This wireless access point product has been verified for basic compatibility with corresponding Intel® Centrino™ mobile technology based notebooks. Notebooks based on Intel Centrino mobile technology do not support proprietary 802.11g performance enhancement features. Data rate features and performance may vary based on the configuration of your notebook and other factors.Intel, the Intel inside Logo, Intel Centrino and the Intel Centrino logo are trademarks or registered trademarks of Intel Corporation or its subsidiaries in the United States and other countries.
PRODUCT SPECIFICATION:
DWL-G700AP > High Speed 2.4GHz (802.11g) Wireless Access Point
Specifications
Standards
• IEEE 802.11b
• IEEE 802.11g
• IEEE 802.3
• IEEE 802.3u
Device Management• Web-based — Internet Explorer v6 or later;
Netscape Navigator v6 or later; or other Java-enabled browsers.
Wireless Signal Rates* With Automatic Fallback
• For 802.11g: 54, 48, 36, 24, 18, 12, 9, and 6Mbps
• For 802.11b: 11, 5.5, 2, and 1Mbps
Security
• 64/128-bit WEP
• WPA (Wi-Fi Protected Access)
• MAC address filtering
• SSID Broadcast Disable function
Wireless Frequency Range • 2.412GHz to 2.462GHz
Wireless Signal Range*• Indoors: Up to 328ft (100 meters)
• Outdoors: Up to 1312ft (400 meters)
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Modulation Technology
• Orthogonal Frequency Division Multiplexing (OFDM)
• Complementary Code Keying (CCK)
• BPSK
• QPSK
Receiver Sensitivity*IEEE 802.11g
• -65dBm @ PER10% in 54M 64QAM
• -66dBm @ PER10% in 48M 64QAM
• -70dBm @ PER10% in 36M 16QAM
• -74dBm @ PER10% in 24M 16QAM
• -77dBm @ PER10% in 18M QPSK
• -79dBm @ PER10% in 12M QPSK
• -81dBm @ PER10% in 9M BPSK
• -82dBm @ PER10% in 6M BPSK
Receiver Sensitivity*IEEE 802.11b
• -82dBm @ PER8% in 11M CCK
• -85dBm @ PER8% in 5.5M CCK
• -87dBm @ PER8% in 2M QBSK
• -87dBm @ PER8% in 1M BPSK
Wireless Transmit Power • 15dBm (32mW)±2dB
External Antenna Type • Detachable dual antennas with 2dB gain
LEDs
• Power
• WLAN
• LAN (10/100)
Power• External Power Supply: DC 5V/2A
• AC Adapter: 100V~120V
Temperature• Operating: 32ºF to 131ºF (0ºC to 55ºC)
• Storing: -4ºF to 149ºF (-20ºC to 65ºC)
Humidity • 5%~95% non-condensing
Certifications• FCC part 15 class B & C
• Wi-Fi
Dimensions
• L = 5.59 inches (142mm)
• W = 4.29 inches (109mm)
• H = 1.22 inches (31mm)
Weight • ~0.44lb (200g)
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Warranty • 1 Year
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Linksys WRT54G:
Wireless-G Broadband Router
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Product Features:
All-in-one Internet-sharing Router, 4-port Switch, and Wireless-G (802.11g) Access Point
Shares a single Internet connection and other resources with Ethernet wired and Wireless-G clients
Wireless data rates up to 54Mbps -- 5 times as fast as Wireless-B (802.11b), but also interoperable with Wireless-B devices (at 11Mbps)
Advanced security: Wi-Fi Protected Access™ (WPA), wireless MAC address filtering, powerful SPI firewall
Product Description:
Wireless-G is the upcoming 54Mbps wireless networking standard that's almost five times as fast as the widely deployed Wireless-B (802.11b) products found in homes, businesses, and public wireless hotspots around the country — but since they share the same 2.4GHz radio band, Wireless-G devices can also interoperate with existing 11Mbps Wireless-B equipment.
Since both standards are built in, you can protect your investment in existing 802.11b infrastructure, and migrate to the new screaming fast Wireless-G standard as your needs grow.
The Linksys Wireless-G Broadband Router is really three devices in one box. First, there's the Wireless Access Point, which lets you connect Wireless-G or Wireless-B devices to the network. There's also a built-in 4-port full-duplex 10/100 Switch to connect your wired-Ethernet devices. Connect four PCs directly, or daisy-chain out to more hubs and switches to create as big a network as you need. Finally, the Router function ties it all together and lets your whole network share a high-speed cable or DSL
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Internet connection, files, and other resources such as printers and hard disk storage space.
To protect your data and privacy, the Wireless-G Broadband Router can encode all wireless transmissions using 128-bit WEP encryption, and also supports industrial-strength Wi-Fi Protected Access™ (WPA) wireless security. The Router protects your PC from most known Internet attacks with a powerful Stateful Packet Inspection firewall. It can also serve as a DHCP Server, supports VPN pass-through, and can be configured to filter internal users' access to the Internet. And even with all this power, set up is a snap with the web browser-based configuration utility.
With the Linksys Wireless-G Broadband Router at the center of your home or office network, you can share a high-speed Internet connection, files, printers, and multi-player games with the flexibility, speed, and security you need!
Verified Linksys products have been tested with Intel® Centrino™ Mobile Technology for compatibility and interoperability, further enhancing your wireless experience.
Linksys WRT54G Wireless-G Router:
Technical Details
All-in-one Internet-sharing router, 4-port switch, and Wireless-G (802.11g) access point
Wireless data rates up to 54 Mbps--5 times faster than 802.11b
Shares a single Internet connection and other resources with Ethernet wired and Wireless- G clients
Interoperates with 802.11b clients at 11 Mbps
Advanced wireless security with 128-bit WEP encryption, MAC, or IP address filtering
Product Description
The Linksys Wireless-G broadband router is really three devices in one box. First, it's a wireless access point, which lets you connect Wireless-G or Wireless-B devices to the network. There's also a built-in four-port full-duplex 10/100 switch to connect your wired-Ethernet devices. Connect four PCs directly, or daisy-chain out to more hubs and switches to create as big a network as you need. Finally, the router function ties it all together and lets your whole network share a high-speed cable or DSL Internet connection.
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To protect your data and privacy, the Wireless-G broadband router can encrypt all wireless transmissions, and it supports the industrial-strength wireless security of 802.1x authentication and authorization. The router can serve as a DHCP server, has NAT technology to protect against Internet intruders, supports VPN pass-through, and can be configured to filter internal users' access to the Internet. Configuration is a snap with the Web browser-based configuration utility.
With the Linksys Wireless-G broadband router at the center of your home or office network, you can share a high-speed Internet connection, files, printers, and multiplayer games with the flexibility, speed, and security you need!
Wireless-G is the 54 Mbps wireless networking standard that's more than four times faster than the widely deployed Wireless-B (802.11b) products found in homes, businesses, and public wireless hotspots around the country. But since they share the same 2.4 GHz radio band, Wireless-G devices can also interoperate with existing 11 Mbps Wireless-B equipment.
Because both standards are built-in, you can protect your investment in existing 802.11b infrastructure, and migrate to the new screaming-fast Wireless-G standard as your needs grow.
For more information on the differences between an access point and a router with access point, see the following table:
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Linksys / WAP4400N / 300Mbps / 802.11n (Draft-N) / Wireless Access Point with Power Over Ethernet (PoE)
Linksys Wireless-N Access Point with Power Over Ethernet
With the growth in high bandwidth applications, such as storage and video in the work place, network performance is essential. Wireless technology is no longer lagging behind wired performance. The introduction of the Linksys Business Series WAP4400N wireless Access Point answers the growing business' need for access, speed and security.
The Access Point uses the very latest wireless networking technology, Wireless-N (draft 802.11n). By overlaying the signals of multiple radios, Wireless-N's “Multiple In, Multiple Out” (MIMO) technology multiplies the effective data rate. Unlike ordinary wireless networking technologies that are confused by signal reflections, MIMO actually uses these reflections to increase the range and reduce “dead spots” in the wireless coverage area.
The Linksys Wireless-N Access Point lets you connect Wireless-N (802.11n), Wireless-G (802.11g) or Wireless-B (802.11b) devices to your wired network so you can add PCs to the network with no cabling hassle. Power over Ethernet support makes it easy to install -- you can mount the Access Point anywhere, even without ready access to a power plug. With appropriate Power over Ethernet support at the other end, you only need to run one cable to the Access Point to deliver both data and power. Of course, you can also use the included AC adapter if your installation point has power available nearby.
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To protect your data and privacy, the Wireless-G Exterior Access Point supports both Wired Equivalent Privacy (WEP) and the industrial-strength wireless security of Wi-Fi Protected Access™ (WPA), encoding all your wireless transmissions with powerful encryption. The MAC Address filter lets you decide exactly who has access to your wireless network, and advanced logging keeps you appraised. Configuration is a snap with the web browser-based configuration utility.
The Linksys Wireless-N Access Point with Power Over Ethernet is the best way to add wireless access to your existing business network.
Specifications:
Device Type: Wireless Access Point
Form Factor: Desktop
Wireless Network Standards: IEEE 802.11gIEEE 802.11bIEEE 802.11n
Wireless Data Transfer Rates: 300 Mbps
Security Protocols: 128-bit WEP64-bit WEPWPA-PersonalWPA-EnterpriseWPA-PSK
Modulation Technology: OFDMDSSS
Networking Standards:IEEE 802.3 Ethernet 10Base-T, IEEE 802.3u Ethernet 100Base-TX
Firewall Features: MAC Address Filtering
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Management: Web Based
10/100/1000 Mbps Ports: 1
Antenna Type: Omni-Directional
Detailed Features
72
Features
Draft 802.11n wireless networking can provide speeds greater than 100Mbps Full backwards compatibility for 802.11b and 802.11g Easy installation and configuration web Interface Supports WEP, WPA-PSK,
WPA2-PSK, WPA2-ENT, WPAENT authentication (802.11i ready) Adjustable Dipole antennaes with MIMO 2x3 Diversity Gigabit Ethernet LAN interface Supports Power over Ethernet (PoE) or external DC power Supports SNMP and intuitive web-based interface WMM wireless QoS support - upgradeable to 802.11e
Latest Owner Reviews
5.05.05.05.0
08mbps wireless...
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PN-54WRT 54MBPS WIRELESS ROUTER
The PN-54WRT 54Mbps Wireless Router integrates firewall, NAT-router and Wireless
AP. The design is dedicated to Small Office/Home Office (SOHO) Wireless network
solution. The PN-54WRT 54Mbps Wireless Router will allow you to connect your
network wirelessly better than ever, sharing Internet Access, files and fun, easily and
securely.
With the most attentive wireless security, the PN-54WRT 54Mbps Wireless Router
provides multiple protection measures. It can be set to turn off wireless network name
(SSID) broadcast so that only stations that have the SSID can be connected. The Router
provides wireless LAN 64/128/152-bit WEP encryption security, and WPA/WPA2 and
WPA-PSK/WPA2-PSK authentication and TKIP/AES encryption security. It also
supports VPN pass-through for sensitive data secure transmission.
The PN-54WRT 54Mbps Wireless Router complies with the IEEE 802.11g/b standards
and adopts 2x to 3x extended Range™ WLAN transmission technology so that
transmission distance is 2-3 times that of traditional 11g/b solutions, up to 855.36m tested
in China. Transmission range is extended to 4-9 times. It is compatible with all IEEE
802.11g and IEEE 802.11b products.
The PN-54WRT 54Mbps Wireless Router provides flexible access control. It has built-in
NAT and DHCP server supporting static IP address distributing. It also supports Virtual
Server and DMZ host for Port Triggering needs, as well as remote management and log
so that network administrators can manage and monitor the network on real time.
The PN-54WRT 54Mbps Wireless Router is easy-to-manage. Quick Setup Wizard is
supported and friendly help messages are provided for every step. So you can configure it
quickly and share Internet access, files and fun.
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Features
Complies with IEEE 802.11g, IEEE 802.11b, IEEE 802.3, IEEE 802.3u standards 1 10/100M Auto-Negotiation RJ45 WAN port, 4 10/100M Auto-Negotiation
RJ45 LAN ports Supports Auto MDI/MDIX Adopts 2x to 3x extended Range™ Shares data and Internet access for users, supporting PPPoE, Dynamic IP, Static
IP, L2TP, Big Pond Cable Internet access Supports 54/48/36/24/18/12/9/6/11/5.5/3/2/1Mbps wireless LAN data transfer
rates Provides 64/128/152-bit WEP encryption security Provides WPA/WPA2 and WPA-PSK/WPA2-PSK authentication and TKIP/AES
encryption security Provides wireless LAN ACL (Access Control List) filtering Built-in NAT and DHCP server supporting static IP address distributing Supports Virtual Server, Special Application, and DMZ host Built-in firewall supporting IP address filtering, Domain Name filtering, and
MAC address filtering Supports TCP/IP, PPPoE, DHCP, ICMP, NAT Supports UPnP, Dynamic DNS, Static Routing, VPN pass-through Supports Flow Statistics Supports ICMP-FLOOD, UDP-FLOOD, TCP-SYN-FLOOD filter Ignores Ping packets from WAN or LAN ports Supports firmware upgrade Supports Remote and Web management
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PN-54AP – 54MBPS WIRELESS ACCESS POINT
The device is 11g Wireless LAN Access Point, Wireless LAN solution compliant with
802.11g standard and IEEE 802.11b. WLAN networking can wirelessly transmit and
receive data, minimizing the need for wired connections, at a speed of up to Fifty-four
megabit per second, you can locate your PC wherever you want without wires and cables.
The device provides users with an access to real-time information anywhere in their
organization. The mobility provides productivity and service, which are not available
under wired networks.
Features
Provide Ethernet to Wireless LAN bridge fully compatible on Ethernet side and fully IEEE 802.3 compatible on the Ethernet side and fully interoperable with IEEE 802.11g compliant equipment
Provide 10/100 BASE-TX Fast Ethernet interface. IEEE 802.11g Infrastructure and Ad-Hoc operating modes. Dynamic date rate scaling at 54, 48, 36, 24, 18, 12, 9 and 6 Mbps for 802.11g Dynamic date rate scaling at 11, 5.5, 2 and 1Mbps for 802.11b Allow auto fallback data rate for optimized reliability, throughput and
transmission range Supports wireless data encryption with 64/128-bit WEP standard for security Supports WDS bridging function Supports wireless security standards WPA Dual diversity antennas for the multi-path environment
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Web-based configuration tools and management
PN-54AP – 54MBPS WIRELESS ACCESS POINT
Specifications
StandardsIEEE 802.11g (Wireless LAN)IEEE 802.3u (Fast Ethernet
Radio Technology802.11b: Direct Sequence Spread Spectrum (DSSS)802.11g: Orthogonal Frequency Division Multiplexing (OFDM)
Transmission Rate 1, 2, 5.5, 6, 11, 12, 18, 22, 24, 36, 48, 54Mbps (auto sense)
Receiver Sensitivity54Mbps: Typical -68dBm @ 10% PER (Packet Error Rate)11Mbps: Typical -81dBm @ 8% PER (Packet Error Rate)
Wireless LAN Frequency Range
2412 ~ 2484 MHz ISM band (channels 1 ~ 14)
Modulation Schemes DBPSK/DQPSK/CCK/OFDM
Media Access Protocol CSMA/CA with ACK
Transmit Power802.11g: Minimum 12dBm typically802.11b: Minimum 15dBm typically
Antenna Type Dual diversity antennas with 2 dB gain
Interface 10/100BASE-TX RJ-45 Ethernet
Network Management Web base configuration via Web Browser
ChannelUSA : 1 ~ 11Europe: 1 ~ 13Japan: 1 ~ 14
Security64/128-bits WEP Encryption/DecryptionWireless Fidelity Protected Access (WPA).
Range CoverageIndoor: 50 ~ 100 meters (depends on environment)Outdoor: 100 ~ 300 meters (depends on environment)
Diagnostic LEDs Power & LAN & WLAN
Dimensions (W x H x D)
139.5 x 114.5 x 29.4 mm (without antenna)
EnviromentOperation Temperature: 0~ 40 °C. Storage Temperature: -25 ~ 70 °C. Storage Temperature: 10% ~ 90% RH, no condensation.
Certifications FCC, CE
TL-WR642G - 108MBPS WIRELESS ROUTER
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The TL-WR642G 108Mbps Wireless Router integrates firewall, NAT-router and
Wireless AP. It's design is dedicated to Small Office/Home Office (SOHO) Wireless
network solution. The TL- WR642G 108Mbps
Wireless Router will allow you to connect your
network wirelessly better than ever, sharing Internet
Access, files and fun, easily and securely.
With the most attentive wireless security, the TL-WR642G 108Mbps Wireless Router
provides multiple protection measures. It can be set to turn off wireless network name
(SSID) broadcast so that only stations that have the SSID can be connected. The router
provides wireless LAN 64/128/152-bit WEP encryption security, and WPA and WPA-
PSK authentication and TKIP/AES encryption security. It also supports VPN pass-
through for sensitive data secure transmission.
Features
1 10/100M Auto-Negotiation WAN RJ45 port, 4 10/100M Auto-Negotiation LAN RJ45 ports
Adopts 2x to 3x extended Range™ and 108M Super G™ technologies Provides 64/128/152-bit WEP encryption security Supports Virtual Server, Special Application, and DMZ host Built-in firewall supporting IP address filtering, Domain Name filtering, and
MAC address filtering Supports access control, parents and network administrators can establish
restricted access policies based on time of day for children or staffs Supports Remote and Web management
5dBi Antenna
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SpecificationsElectrical Specification
Frequency Range 2400 - 24835 MHz
Impedance 50 ohm nominal
Insertion Loss -2.5dB
VSWR .2.0
Gain 5dBi (Max.)
Polarization Vertical
Radiation Omni
Electrical Wave 1/4? Dipole
Physical Properties
Connector Reverse Polarity SMA Plug
Connector Base Brass with Gold Plate
Swivel Mechanism PC/ABS, ABS
Cable RG-174 Cable
TL-WR642G - 108MBPS WIRELESS ROUTER
Specifications
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Protocol & StandardsIEEE 802.11g, IEEE 802.11b, IEEE 802.3, IEEE 802.3u, IEEE 802.3x, IEEE 802.1x, CSMA/CA, CSMA/CD, TCP/IP, DHCP, ICMP, NAT, PPPoE
PortsLAN 4 10/100M Auto MDI/MDIX RJ45 ports
WAN 1 10/100M Auto MDI/MDIX RJ45 port
Wireless Parameters
Frequency Band
2.4~2.4835GHz
Data Transfer Rates
Super G™ : 108M
11g: 54/48/36/24/18/12/9/6M (Auto-Sense)
11b: 11/5.5/3/2/1M (Auto-Sense)
Channel
1~11 (US, Canada)
1~13 (Europe)
1~14 (Japan)
Extend Frequency
DSSS
ModulationBPSK, QPSK, CCK and OFDM (BPSK/QPSK/16-QAM/ 64-QAM)
Transmission Distance
Indoor up to 100m, outdoor up to 300m (Standard transmission distance, it is limited in an environment). Indoor up to 200m, Outdoor up to 830m (Adopt 2x to 3x eXtended Range™ WLAN transmission technology, it is limited in an environment)
RF Power 18dBm (Typical)
Antenna3dBi
Dipole Antenna(detachable reverse SMA connector)
Network Media
10BASE-T: UTP category 3, 4, 5 cable (maximum 100m)EIA/TIA-568 100? STP (maximum 100m)100BASE-TX: UTP category 5, 5e cable (maximum 100m)EIA/TIA-568 100? STP (maximum 100m)
LED Indicators
Port Link/Act, Speed
Else Power, System, WLAN
PowerAC power adapter: 9V~ 0.8AConsumption: 7W (Max)
Safety & Emission FCC, CE
Dimensions (W x D x H) 7.3 in. x 5.7 in. x 1.7 in.(186 mm x 146 mm x 44 mm)
Environment Operating Temperature: 0?~40? (32?~104?);
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Storage Temperature: -40~70? (-40?~158?)Operating Humidity: 10%~90% non-condensing;Storage Humidity: 5%~95% non-condensing
OPPORTUNITIES AND CHALLENGES
Wireless broadband is an exciting new technology enabling various fixed and mobile
applications targeting different vertical markets serving residential and enterprise user
segments. This not only creates new opportunities to serve but also places new demands
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on the networks. As service providers introduce these new technologies to offer higher
bandwidth based applications, they need a service delivery platform that supports not
only current and new requirements, but also drive new business models involving
expanded ecosystems. The advent of wireless broadband will drive convergence of
telecom world, the Internet and the IT and enabling quad play - voice, data, video and
mobility. This will force all the service providers, existing and new, to look at the
Services layer not only for revenue growth opportunities but also to differentiate and gain
competitive advantage. As many of the applications and products have shorter life cycles,
service providers have to create and maintain an ecosystem of partners who can deliver
compelling solutions across the value chain with minimum development risk and faster
market introduction with opportunities to serve different market segments with
compelling applications come different challenges. From the business side there will be
demand on managing ecosystem partners, customers and services to cater to these various
segments. From the network side there will be demand on provisioning capabilities,
flexible billing models, delivery and enablement of services and revenue assurance
mechanisms. Service providers should use the Services layer as a key control point of
their network to define the business strategy and competitive positioning in the market
place with the ability to define, create and deploy new services.
CONCLUSION
Innovative applications and services around wireless broadband technology will drive market adoption. Service providers need to look at Services layer as a key business asset to deliver carrier-grade class of services, flexible life-cycle management for new services, as well as leveraging existing assets. Wireless broadband technologies like Metro Wi-Fi, Mesh Networks and Wi-MAX bring capabilities for a wide range of fixed/mobile service providers, wireless ISPs, vertical markets and public/private safety authorities. But it is the Service layer proposition with rich content to the consumer and personalization
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through a portfolio of end-user applications/services, rapid service creation enablement, delivery and management of services that will help service providers to differentiate in the market place and to drive revenues.
Wireless technology round
Wireless technology round
Wi-Fi (802.11b)
.
Bluetooth GPRS (General Packet Radio Service)
Wireless technology round
11 Mbps 1 Mbps 115 kbps
Wireless technology round
2 to 4 Mbps 721 kbps 42 to 84 kbps
Wireless technology round
100 meters (300 meters
Outdoors).
Depending on the variant from 6 to 100 meters
City-wide
Wireless technology round
2.4 GHz Personal Identification Number (PIN)
SGSN (Serving GPRS Support Node) handles a mobile station's registration and authentication into the GPRS network.
Wireless technology round
WEP (wired equivalent privacy), SSID (Service Set Identifier)
2.45 GHz GSM 900 / 1800 /1900
Wireless technology round
The wireless avatar of Ethernet, the most popular LAN protocol.
Low power consumption; supports voice.
Ubiquitous
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P. C. MANAGEMENT
AND INDEXING
PC NO PC NAME WORKGROUP DEPT E-MAIL-ID
PC001 PC002 PC003 PC004 PC005 PC006 PC007 PC008
84
PC009 PC010 PC011 PC012 PC013 PC014 PC015 PC016 PC017 PC018 PC019 PC020 PC021 PC022 PC023 PC024 PC025 PC026 PC027 PC028 PC029 PC030 PC031 PC032 PC033 PC034 PC035 PC036 PC037 PC038 PC039 PC040 PC041 PC042 PC043
PC MANAGEMENT AND INDEXING
P C CODE
PC NO CPU NO HDD NO MEMORY NO MIC NO KEY BOARD NO MONITER CABINATE NO
PC001 CPU001 HDD001 RAM001 MIC001 KEY001 MON001 CAB001PC002 CPU002 HDD002 RAM002 MIC002 KEY002 MON002 CAB002PC003 CPU003 HDD003 RAM003 MIC003 KEY003 MON003 CAB003PC004 CPU004 HDD004 RAM004 MIC004 KEY004 MON004 CAB004PC005 CPU005 HDD005 RAM005 MIC005 KEY005 MON005 CAB005PC006 CPU006 HDD006 RAM006 MIC006 KEY006 MON006 CAB006PC007 CPU007 HDD007 RAM007 MIC007 KEY007 MON007 CAB007
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PC008 CPU008 HDD008 RAM008 MIC008 KEY008 MON008 CAB008PC009 CPU009 HDD009 RAM009 MIC009 KEY009 MON009 CAB009PC010 CPU010 HDD010 RAM010 MIC010 KEY010 MON010 CAB010PC011 CPU011 HDD011 RAM011 MIC011 KEY011 MON011 CAB011PC012 CPU012 HDD012 RAM012 MIC012 KEY012 MON012 CAB012PC013 CPU013 HDD013 RAM013 MIC013 KEY013 MON013 CAB013PC014 CPU014 HDD014 RAM014 MIC014 KEY014 MON014 CAB014PC015 CPU015 HDD015 RAM015 MIC015 KEY015 MON015 CAB015PC016 CPU016 HDD016 RAM016 MIC016 KEY016 MON016 CAB016PC017 CPU017 HDD017 RAM017 MIC017 KEY017 MON017 CAB017PC018 CPU018 HDD018 RAM018 MIC018 KEY018 MON018 CAB018PC019 CPU019 HDD019 RAM019 MIC019 KEY019 MON019 CAB019PC020 CPU020 HDD020 RAM020 MIC020 KEY020 MON020 CAB020PC021 CPU021 HDD021 RAM021 MIC021 KEY021 MON021 CAB021PC022 CPU022 HDD022 RAM022 MIC022 KEY022 MON022 CAB022PC023 CPU023 HDD023 RAM023 MIC023 KEY023 MON023 CAB023PC024 CPU024 HDD024 RAM024 MIC024 KEY024 MON024 CAB024PC025 CPU025 HDD025 RAM025 MIC025 KEY025 MON025 CAB025PC026 CPU026 HDD026 RAM026 MIC026 KEY026 MON026 CAB026PC027 CPU027 HDD027 RAM027 MIC027 KEY027 MON027 CAB027PC028 CPU028 HDD028 RAM028 MIC028 KEY028 MON028 CAB028PC029 CPU029 HDD029 RAM029 MIC029 KEY029 MON029 CAB029PC030 CPU030 HDD030 RAM030 MIC030 KEY030 MON030 CAB030PC031 CPU031 HDD031 RAM031 MIC031 KEY031 MON031 CAB031PC032 CPU032 HDD032 RAM032 MIC032 KEY032 MON032 CAB032PC033 CPU033 HDD033 RAM033 MIC033 KEY033 MON033 CAB033PC034 CPU034 HDD034 RAM034 MIC034 KEY034 MON034 CAB034PC035 CPU035 HDD035 RAM035 MIC035 KEY035 MON035 CAB035PC036 CPU036 HDD036 RAM036 MIC036 KEY036 MON036 CAB036PC037 CPU037 HDD037 RAM037 MIC037 KEY037 MON037 CAB037PC038 CPU038 HDD038 RAM038 MIC038 KEY038 MON038 CAB038PC039 CPU039 HDD039 RAM039 MIC039 KEY039 MON039 CAB039PC040 CPU040 HDD040 RAM040 MIC040 KEY040 MON040 CAB040PC041 CPU041 HDD041 RAM041 MIC041 KEY041 MON041 CAB041PC042 CPU042 HDD042 RAM042 MIC042 KEY042 MON042 CAB042PC043 CPU043 HDD043 RAM043 MIC043 KEY043 MON043 CAB043
INDEXING ACCORDING TO CPU
PC NAME CPU NO MAKE TYPE SPECIFICATION CPU001 CPU002 CPU003 CPU004 CPU005 CPU006 CPU007 CPU008
86
CPU009 CPU010 CPU011 CPU012 CPU013 CPU014 CPU015 CPU016 CPU017 CPU018 CPU019 CPU020 CPU021 CPU022 CPU023 CPU024 CPU025 CPU026 CPU027 CPU028 CPU029 CPU030 CPU031 CPU032 CPU033 CPU034 CPU035 CPU036 CPU037 CPU038 CPU039 CPU040 CPU041 CPU042 CPU043
INDEXING ACCORDING TO HARD DISK
P C NAME HDD NO TYPE SPECIFICATION
HDD001 HDD002 HDD003 HDD004 HDD005 HDD006 HDD007 HDD008 HDD009 HDD010
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HDD011 HDD012 HDD013 HDD014 HDD015 HDD016 HDD017 HDD018 HDD019 HDD020 HDD021 HDD022 HDD023 HDD024 HDD025 HDD026 HDD027 HDD028 HDD029 HDD030 HDD031 HDD032 HDD033 HDD034 HDD035 HDD036 HDD037 HDD038 HDD039 HDD040 HDD041 HDD042 HDD043
INDEXING ACCORDING TO MEMORY
PC NAME MEMORY NO TYPE SPECIFICATION RAM001 RAM002 RAM003 RAM004 RAM005 RAM006 RAM007 RAM008 RAM009 RAM010 RAM011 RAM012
88
RAM013 RAM014 RAM015 RAM016 RAM017 RAM018 RAM019 RAM020 RAM021 RAM022 RAM023 RAM024 RAM025 RAM026 RAM027 RAM028 RAM029 RAM030 RAM031 RAM032 RAM033 RAM034 RAM035 RAM036 RAM037 RAM038 RAM039 RAM040 RAM041 RAM042 RAM043
INDEXING ACCORDING TO KEYBOARD
PC NAME KEY BOARD NO MAKE MODEL NO SERIAL NO SPECIFICATION KEY001 KEY002 KEY003 KEY004 KEY005 KEY006 KEY007 KEY008 KEY009 KEY010 KEY011 KEY012 KEY013
89
KEY014 KEY015 KEY016 KEY017 KEY018 KEY019 KEY020 KEY021 KEY022 KEY023 KEY024 KEY025 KEY026 KEY027 KEY028 KEY029 KEY030 KEY031 KEY032 KEY033 KEY034 KEY035 KEY036 KEY037 KEY038 KEY039 KEY040 KEY041 KEY042 KEY043
INDEXING ACCORDING TO MONITER
PC NAME MONITER MAKE MODEL NO SERIAL NO SPECIFICATION
MON001
MON002
MON003
MON004
MON005
MON006
MON007
MON00
90
8
MON009
MON010
MON011
MON012
MON013
MON014
MON015
MON016
MON017
MON018
MON019
MON020
MON021
MON022
MON023
MON024
MON025
MON026
MON027
MON028
MON029
MON030
MON031
MON032
MON033
MON034
MON035
91
MON036
MON037
MON038
MON039
MON040
MON041
MON042
MON043
INDEXING ACCORDING TO MOUSE
PC NAME MIC NO MAKE MODEL NO SERIAL NO SPECIFICATION MIC001 MIC002 MIC003 MIC004 MIC005 MIC006 MIC007 MIC008 MIC009 MIC010 MIC011 MIC012 MIC013 MIC014 MIC015 MIC016 MIC017 MIC018 MIC019 MIC020 MIC021 MIC022 MIC023 MIC024 MIC025 MIC026 MIC027 MIC028 MIC029 MIC030 MIC031
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MIC032 MIC033 MIC034 MIC035 MIC036 MIC037 MIC038 MIC039 MIC040 MIC041 MIC042 MIC043
1. What is wireless networking?
The term wireless networking refers to technology that enables two or more computers
to communicate using standard network protocols, but without network cabling. Strictly
speaking, any technology that does this could be called wireless networking. The
current buzzword however generally refers to wireless LANs. This technology, fuelled
by the emergence of cross-vendor industry standards such as IEEE 802.11, has
produced a number of affordable wireless solutions that are growing in popularity with
business and schools as well as sophisticated applications where network wiring is
impossible, such as in warehousing or point-of-sale handheld equipment.
2. What is a wireless network made up of?
There are two kinds of wireless networks:
a. An ad-hoc or peer-to-peer wireless network consists of a number of computers each
equipped with a wireless networking interface card. Each computer can
communicate directly with all of the other wireless enabled computers. They can
share files and printers this way, but may not be able to access wired LAN
resources, unless one of the computers acts as a bridge to the wired LAN using
special software. (This is called "bridging")
b. Ad-Hoc or Peer-to Peer Networking.
Each computer with a wireless interface can communicate directly with all of the
others.
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c. A wireless network can also use an access point, or base station. In this type of
network the access point acts like a hub, providing connectivity for the wireless
computers. It can connect (or "bridge") the wireless LAN to a wired LAN, allowing
wireless computer access to LAN resources, such as file servers or existing Internet
Connectivity.
There are two types of access points:
i. Dedicated hardware access points (HAP) such as Lucent's Wave LAN, Apple's
Airport Base Station or WebGear's AviatorPRO. Hardware access points offer
comprehensive support of most wireless features, but check your requirements
carefully.
ii. Software Access Points which run on a computer equipped with a wireless network
interface card as used in an ad-hoc or peer-to-peer wireless network. The Vicomsoft
InterGate suites are software routers that can be used as a basic Software Access
Point, and include features not commonly found in hardware solutions, such as
Direct PPPoE support and extensive configuration flexibility, but may not offer the
full range of wireless features defined in the 802.11 standard.
With appropriate networking software support, users on the wireless LAN can share
files and printers located on the wired LAN and vice versa. Vicomsoft's solutions
support file sharing using TCP/IP.
Hardware Access Point.
Wireless connected computers using a Hardware Access Point.
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Software Access Point.
Wireless connected computers using a Software Access Point.
3. What is IEEE 802.11?
Wireless networking hardware requires the use of underlying technology that deals
with radio frequencies as well as data transmission. The most widely used standard
is 802.11 produced by the Institute of Electrical and Electronic Engineers (IEEE).
This is a standard defining all aspects of Radio Frequency Wireless networking.
4. Can I mix wireless equipment from different vendors?
Because most wireless networking hardware vendors support the 802.11 standard
they can inter operate. However, we recommend verification as the standard is a
fairly recent one, and does specify two different methods for wireless
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communications; Frequency Hopping (FH) and Direct Sequence Spread Spectrum
(DSSS or DS), which are not interoperable.
When purchasing wireless networking hardware from separate vendors be sure to
obtain guarantees from the vendors that the hardware will interoperate and follows
the standards.
Within a short time we expect all new wireless cards, like Ethernet cards, to become
inexpensive, ubiquitous and totally interoperable.
Also of note is that the latest version of the standard defines 11mbps and 5.5mbps
networking, with support for the older standard 1mbps and 2mbps speeds. This
provides some compatibility with different or older equipment. Note that this new
standard covers DS-type Networks, not FH types.
Software access points such as InterGate which uses the wireless interface of the
host computer should have no compatibility issues with third party wireless
hardware, as long as standards are followed. Typically wireless hardware is
identified to the software as a network interface, and therefore can be used in the
same way as any other network card.
5. If my computer is connected to a wireless LAN, can it communicate with computers on a wired LAN as well?
To do this you will need some sort of bridge between the wireless and wired
network. This can be accomplished either with a hardware access point or a
software access point. Hardware access points are available with various types of
network interfaces, such as Ethernet or Token Ring, but typically require extra
hardware to be purchased if your networking requirements change.
If networking requirements go beyond just interconnecting a wired network to a
small wireless network, a software access point may be the best solution.
A software access point does not limit the type or number of network interfaces you
use. It may also allow considerable flexibility in providing access to different
network types, such as different types of Ethernet, Wireless and Token Ring
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networks. Such connections are only limited by the number of slots or interfaces in
the computer used for this task.
Further to this the software access point may include significant additional features
such as shared Internet access, web caching or content filtering, providing
significant benefits to users and administrators.
6. What is the range of a wireless network?
Each access point has a finite range within which a wireless connection can be
maintained between the client computer and the access point. The actual distance
varies depending upon the environment; manufacturers typically state both indoor
and outdoor ranges to give a reasonable indication of reliable performance. Also it
should be noted that when operating at the limits of range the performance may
drop, as the quality of connection deteriorates and the system compensates.
Typical indoor ranges are 150-300 feet, but can be shorter if the building
construction interferes with radio transmissions. Longer ranges are possible, but
performance will degrade with distance.
Outdoor ranges are quoted up to 1000 feet, but again this depends upon the
environment.
There are ways to extend the basic operating range of Wireless communications, by
using more than a single access point or using a wireless relay /extension point.
7. How many wireless networked computers can use a single access point?
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This depends upon the manufacturer. Some hardware access points have a
recommended limit of 10, with other more expensive access points supporting up to
100 wireless connections. Using more computers than recommended will cause
performance and reliability to suffer.
Software access points may also impose user limitations, but this depends upon the
specific software, and the host computer's ability to process the required
information.
8. Can I have more than one access point?
Yes, multiple access points can be connected to a wired LAN, or sometimes even to
a second wireless LAN if the access point supports this.
In most cases, separate access points are interconnected via a wired LAN, providing
wireless connectivity in specific areas such as offices or classrooms, but connected
to a main wired LAN for access to network resources, such as file servers.
Multiple Access Points.
Wireless connected computers using Multiple Access Points.
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If a single area is too large to be covered by a single access point, then multiple
access points or extension points can be used. -- Note that an "extension point" is
not defined in the wireless standard, but have been developed by some
manufacturers. When using multiple access points, each access point wireless area
should overlap its neighbors. This provides a seamless area for users to move
around in using a feature called "roaming.” (See the next question for an
explanation of Roaming)
Some manufacturers produce extension points, which act as wireless relays,
extending the range of a single access point. Multiple extension points can be strung
together to provide wireless access to far away locations from the central access
point.
Extension Point.
Wireless connected computers using an Access Point with an Extension Point.
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9. What is Roaming?
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A wireless computer can "roam" from one access point to another, with the software
and hardware maintaining a steady network connection by monitoring the signal
strength from in-range access points and locking on to the one with the best quality.
Usually this is completely transparent to the user; they are not aware that a different
access point is being used from area to area. Some access point configurations
require security authentication when swapping access points, usually in the form of
a password dialog box.
Access points are required to have overlapping wireless areas to achieve this as can
be seen in the following diagram:
Roaming.
A user can move from Area 1 to Area 2 transparently. The Wireless networking
hardware automatically swaps to the Access Point with the best signal.
Not all access points are capable of being configured to support roaming. Also of
note is that any access points for a single vendor should be used when
implementing roaming, as there is no official standard for this feature.
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10.Can I use a wireless network to interconnect two LANs?
Yes. Wireless networking offers a cost-effective solution to users with difficult
physical installations such as campuses, hospitals or businesses with more than one
location in immediate proximity but separated by public thoroughfare. This type of
installation requires two access points. Each access point acts as a bridge or router
connecting its own LAN to the wireless connection. The wireless connection allows
the two access points to communicate with each other, and therefore interconnect
the two LAN's.
LAN to LAN Wireless Communications
A Hardware Access Point providing wireless connectivity to local computers and a
software access point. The software access point provides Wired Ethernet network
2 computers access to Wired Network 1.
Note that not all hardware access points have the ability to directly interconnect to
another hardware access point, and that the subject of interconnecting LAN's over
wireless connections is a large and complex one, and is beyond the scope of this
introduction.
11.Is it true that wireless networking is only good for laptop computers?
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Although wireless networking offers obvious benefits to users of laptops who move
from location to location throughout the day, there are benefits for users of fixed
position computers as well:
Many schools and businesses have unsuitable building layouts or walls that cannot
be wired for various reasons making it difficult or impossible to build a wired
network. Wireless networking in these environments is a very cost effective
alternative also providing future flexibility.
In cases where a small number of computers are separated from a main network a
wireless link may be more cost effective than network cabling although the latter is
perfectly feasible.
Temporary wireless LANs can easily be created for exhibitions, school or business
projects, all without any trailing cabling.
12. What about security?
Wireless communications obviously provide potential security issues, as an intruder
does not need physical access to the traditional wired network in order to gain
access to data communications. However, 802.11 wireless communications cannot
be received --much less decoded-- by simple scanners, short wave receivers etc.
This has led to the common misconception that wireless communications cannot be
eavesdropped at all. However, eavesdropping is possible using specialist
equipment.
To protect against any potential security issues, 802.11 wireless communications
have a function called WEP (Wired Equivalent Privacy), a form of encryption
which provides privacy comparable to that of a traditional wired network. If the
wireless network has information that should be secure then WEP should be used,
ensuring the data is protected at traditional wired network levels.
Also it should be noted that traditional Virtual Private Networking (VPN)
techniques will work over wireless networks in the same way as traditional wired
networks.
13.How can I use a wireless network to share an Internet connection?
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Once you realise that wireless cards are analogous to ethernet cards and that empty
space is analogous to ethernet cabling, the answer to this question becomes clear.
To share an Internet connection across a LAN you need two things:
An Internet sharing hardware device or software program
A LAN
If your LAN is wireless, the same criteria apply. You need a hardware or software
access point and a wireless LAN. Any computer equipped with a wireless network
card running suitable Internet sharing software can be used as a software access
point.
A hardware access point may provide Internet Sharing capabilities to Wired LAN
computers, but does not usually provide much flexibility beyond very simple
configurations.
Software Access Point.
Wireless connected computers using a Software Access Point for shared Internet
access.
Hardware Access Point.
Wireless connected computers using a Hardware Access Point for shared Internet access.
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14. If I have more than one hardware access point, how can I share a single Internet connection?
If an existing wired LAN already has an Internet connection, then the hardware
access points simply connect to your LAN and allow wireless computers to access
the existing Internet connection in the same way as wired LAN computers.
Multiple Access Points.
Wireless connected computers using Multiple Access Points.
If there is no existing Internet connection, then this depends on the access point:
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Software Access Point sharing one Internet connection.
Wireless connected computers using Multiple Access Points. All wired and wireless
computers access the Internet through a single software access point.
If an access point provides some form of Internet sharing itself, then having
multiple such access points connected to a wired LAN may require some special
configuration, or possibly may require an additional Internet sharing device or
software program.
15.If I use a wireless network to connect to the Internet does my ISP need a wireless network too?
If you use a wireless network to connect to the Internet, the wireless part only
concerns your LAN. The communications link from your LAN to your Internet
service provider (ISP) would be identical whether or not you had a wireless
network. For example, if you connected an Ethernet network to the Internet via a
56K modem, when you upgraded your network to use wireless, you would still use
the same 56K modem to connect to the Internet.
16.Can networking software identify a wireless computer in the same way it can identify an Ethernet computer on the network?
Wireless cards look just like Ethernet cards to your network drivers. In fact,
wireless networking cards have unique MAC hardware addresses that are formatted
like Ethernet hardware addresses allocated from the same standards organization.
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BIBLOGRAPHY
WEB SITES:-
1. www.pronet.com 2. www.cisco.com 3. www.dlink.com 4. www.linksys.com 5. www.wikipedia.com 6. www.google.com
Books:-
1. COMPUTER NETWORKING BY FROZEN 2. COMPUTER NETWORKING BY TENEN BUM3. COMPUTER NETWORK ELEMENTS BY R.P.GUPTA 4. WIRELESS NETWORKING BY C.P. PANDAY
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