1
SEMINAR REPORT ON
WiFi Technology
SUBMITTED BY: Tejas.S.Mahajan
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CERTIFICATE S.J.V.P.M.’S POLYTECHNIC Fattechand Marg, Chinchwad, pune-411 pune-411 033. This is to certify that student Mr.Tejas.S.Mahajan Mr.Tejas.S.Mahajan has successfully presented a Seminar on topic
“WiFi Technology.”
Mrs. Tingre S.S. Subject Teacher
Mrs. Deshpande A.H. H.O.D
Mr. Thite A.B. PRINCIPAL
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Index:1)
Introduction.
2)
Specific Part.
3)
WiFi Cards.
4)
Hotspot.
5)
WiFi Security.
6)
Access Point.
7)
Function Of The Working Parts.
8)
Future WiFi Advancement.
9)
Overview Of Material.
10)Benefits Of WiFi. 11)Conclusion.
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Introduction Computers, laptops, cell phones and palm pilots are examples of mechanisms that can grant the user internet access. Although computers and laptops are capab le of having normal internet connection (i.e. Ethernet connection), they are also able to have internet access through wireless technology. Cell phones and palm pilots can only be con nected to the internet by wireless connection. c onnection. Wireless networking is possible through the technology of wireless-fidelity. wireless-fidelity. Wireless-fidelity or WiFi WiFi as most people call it allows a ubiquitous internet connection to be broadcasted through radio waves. Its purpose serves directly to the users looking for internet access devoid of any cords or wires. Summary Radio waves are the keys which make WiFi networking possible. These radio signals are transmitted from antennas and routers and are picked up by WiFi receivers such as computers and cell phones that are equipped with WiFi cards. Whenever a computer receives any of the signals within the range of a WiFi WiFi network which is usually 300 – 500 feet for antennas and 100 – 150 feet for routers, the WiFi card will read the signals and thus create an internet connection between the user and the network without the use of a cord. Usually the connection speed is increases as the computer gets closer to the main source of the signal and decreases when the computer gets further awa y. With that in mind, think of the WiFi card as being an invisible cord that con nects your computer to the antenna for a direct connection to the internet. Many new laptops already come with a WiFi card built in and in many cases you don’t have to do anything to start WiFi WiFi which is one of the best things about a bout it and how simple it is. WiFi cards can be external or internal, meaning that if a WiFi card is not installed in your computer, you may purchase a USB antenna attachment and have it externally connect to your USB port, or have an antennaequipped expansion card installed directly to the computer. Laptops without a built in WiFi card is usually installed the external way while PCs have it installed internally. internally. Once a connection is established between the user and the network, the user will be prompted with a login screen and an d password if it is a fee-based type network. Though there’re also free-based network connections as well in some areas. Wifi Wifi networking around the world is creating hot spots in cities where anyone with a laptop can wirelessly plug into the internet. A hotspot is a connection point p oint for a WiFi network. It is a small box that is hardwired into the internet. There are many WiFi WiFi hotspots now available in public places like restaurants, hotels, libraries and airports. You You can also create your own hotspot in your home. Research has shown that within the next 10 years, hot spots will be all over urban and suburban vicinities.
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Design
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Here is a simple and easy to understand diagram of the basics of WiFi networking. The main source of the network is shown on the diagram as an antenna. The purpose of the
7 WiFi Technology antenna is to send radio signals to the people who want access a ccess to the internet by using laptops and palm pilots. In order for the person to gain access to the internet, they must have WiFi equipped products shown on the diagram. The diagram also features ho w WiFi WiFi cards can receive these radio signals into their WiFi WiFi receivers and have wireless connection to the internet. The diagram represents the person with the most important information of what features you need to understand of how WiFi spreads the net in a specific location. It also gives the person insight of how wireless technology work through radio waves and how it functions.
Specific Parts Radio Signals When it comes to WiFi technology, technology, radio signals are the most essential and an d crucial components. They determine if you have internet access and what speed the connection is running on. The basic concept concep t of radio signals used in WiFi networking is usually compared to that of walkie talkies. These walkie talkies can transmit and receive radio signals which makes possible to communicate with o ne another. When you literally talk into the walkie talkie, it is fixed to a radio frequency and broadcasted with the antenna. The person holding the other walkie talkie receives the radio transmission through its antenna and decodes deco des the words from the original walkie talkie. Thus the same idea is used when it comes to radio signals in WiFi WiFi networking. The main sources of radio waves come from the antenna or router which transmits these waves to another antenna, in this case, WiFi cards, which give a direct signal to the user the ability to have internet access. For a better understanding, look back again at the photographic representation in the summary section. The antenna is placed on top of a building and emits radio waves within the vicinity. vicinity. Notice that people with internet devices are receiving these signals to gain access to the internet. The IEEE (Institute of Electrical and Electronics Engineers) has produced a set of standards and specifications for wireless networks under the title “IEEE 802.11” that defines the format and structure of radio signals sent out by WiFi WiFi networking routers and antennas. Currently there are three forms of the 802.11 standard proposed by the IEEE: 802.11b, which came before 802.11a, and then 802.11g as its last form. WiFi WiFi radios that work with 802.11b and 802.11g broadcasts at a frequency rate of 2.4 GHz while those that comply with the 802.11a form broadcasts at 5GHz. The higher frequency allows faster data rates. Each standard has advantages, but 802.11g has the speed, compatibility, compatibility, and range to replace 802.11b as the most common configuration of WiFi. Here is a chart that represents the main differences of each standard.
Standard Speed
802.11b 11 Mbps
802.11a 54 Mbps
802.11g 54Mbps
8 WiFi Technology Range Frequency
Acceptance
100-150 feet indoors 2.4GHz, a band already crowded with cordless phones Hot spots are already established using 802.11b. Equipment is readily available
27-7 27-75 5 fee feett ind indoo oors rs
100100-15 150 0 fee feett ind indoo oors rs
5GHz, an uncrowded band
2.4GHz, still a crowd of cordless phones and microwaves 802.11g is compatible with the specs for 802.11b, meaning it can be used on a network based on b or g versions.
More common in corporate and office environments.
The standards 802.11a and 802.11g use much more explicit encoding techniques that contribute to the much higher data rates. This is known as orthogonal frequency-division multiplexing (OFDM). As for 802.11b, it is called Complimentary Code Keying (CCK). If you wish to find out more information abou t OFDM and CCK see this page for more details (http://computer.howstuffworks.com/framed.htm?parent=wir (http://computer.howstuffworks.com/framed.htm?parent=wirelesselessnetwork.htm&url=http://www.winlab.rutgers.edu/~aanaik/FHSS.doc). network.htm&url=http://www .winlab.rutgers.edu/~aanaik/FHSS.doc). The three radio standards in wireless networking have the ability to chan ge frequencies. The 802.11b cards can indirectly transmit radio signals onto any of the three bands or they can split the available bandwidth into many channels and does the term “frequency hop” between them. What’s What’s helpful about frequency hopping is that it overcomes interference from other people who are using the same radio signal and changes frequency various times per second. This allows numerous WiFi cards under the same radio signal to talk concurrently with no interference with each other o ther..
WiFi Cards In order for computers to receive these radio signals, a network adapter must be installed on the computer. The network adapter in this case is called the WiFi Card and it can take several physical forms. For laptops, this card will be a PCMCIA card in which you insert to the PCMCIA slot on the laptop. The other way is to buy a external adapter and plug it into a USB port. For personal computers, you can install plug-in PCI cards or a small external adapter for the USB port just like the one used for laptops. A network adaptor should be capable to use in any operating system such as WINDOWS, MAC OS, LINUX and UNIX as long as the driver for the adapter is accessible to down load or install. As you already know, there are three forms of standards used for wireless networking: 802.11b, 802.11a, and 802.11g. Therefore, there are three different kinds of WiFi cards that are available to purchase. The recommended WiFi card to buy is the 802.11g because it has the advantage of higher speeds than the 802.11b (see the chart in the radio signals section). Although it is bit more expensive than the 802.11b, it is still worth the cost. A hotspot which contains 802.11 standards can hold u p to as much as 100 802.11 cards within the vicinity. Below are pictures of how h ow WiFi cards appear and how it fits in the MCMCIA slot on the laptop.
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These three items are examples of the USB versions of the WiFi cards. They are often small and easy to carry around. This is the external WiFi card indicating that it is an exterior item.
Hotspots When laptops are equipped with WiFi WiFi cards, it can very well connect to the wireless hotspot. As mentioned earlier, hot spots are connection points for WiFi networks. They are simply locations where wireless internet is available for those who have internet ready instruments (i.e. computers, laptops, cell phones and palm pilots). Once the internet connection has been established, a log-on screen will appear for most computers and laptops. This occurs when you have attempted to use a wireless network connection that is a fee-based type, meaning you must use your credit card and pay pa y to be a member of that certain internet connection. There are also free-based type wireless connections available as well. As reliable as it sounds having internet connection without the use of
10 WiFi Technology cords, wireless internet is very exposed to hackers and very insecure in most cases. Hackers can track down what you are looking at and can implant viruses such as worms and Trojans and can even access your data! That is wh y people use firewall on their connection to prevent any an y harm caused by hackers. Firewall is a security device that controls access from the internet to a local network. In order to securely access a company’ co mpany’ss internal network, you will need Virtual Private Networking (VPN) software on both the laptop an d the company’s internal servers. Companies in the past have lost all data on all computers because a hacker simply bypassed the system and literally deleted all files crucial to the company compan y. The VPN system was made to have an incident like that ever from happening. To understand more of how VPN works b y visual, a diagram is represented below.
WiFi Security Some Hotspots require WEP key to connect that is the connection is considered to be private or secure. As for open connections, anyone with a WiFi card can gain access to that hotspot. WEP stands for Wired Equivalence Privacy. Privacy. It is considered co nsidered to be a complex encryption system that is made up of two differences. The first is the 64-bit encryption and the other is the 128-bit encryption. The 64-bit encryption was the original standard until it was easily bypassed. For more explanation of what went wrong with WEP see (http://www.nwfusion.com/research/2002/0909wepprimer (http://www.nwfusion.com/research/2002/0909wepprimer.html) .html) for more details. With the 64-bit encryption out of the way, way, the new and improved 128-bit encryption was made. It is much secure and is what wha t most people use to enable WEP. WEP. So in order for a user to gain access to the internet under WEP, WEP, the user must input the WEP key code. Think of it as a simple password.
Access Points Access points are often combined with other network functions. It is very likely that you will discover a separate access point that just plugs into a wired Local Area Network
11 WiFi Technology (LAN). If you already have more than one computer hooked together on the same network and want to have a good hotspot, you can buy a wireless access point and plug it in to the network. As mentioned earlier, radio signals can be received and transmitted by an antenna and a router. The router is an example of an access point of h ow multiple computers can be connected together in the same network both including the use of wires and wireless technology. So once you turn on your access point on, you will have a hotspot in your home and will have radio signal within a 100 feet radius. As for antennas, they have a higher signal transmission at a 300-500 feet radius. That is why hotels, campuses, libraries, etc, anything that is larger than your home is required to use antennas rather than routers. Below are two different kinds of routers used to con nect multiple computers on the same connection.
The physical designs of access points various from one brand to the other. Here you can see one of NetGear’s router and on the right, Linksys’s wireless router have different physical forms. Some look like devices that were intended to be placed in a standing position jut like the router on the right. Others have those normal flat looking routers like the one on the left. Some have internal antennas (which are not shown here) and others have short vertical antennas permanently affixed to the router just like the ones shown here. Regardless of its size and shape, all access points consist of a radio that transmits and receive signals and data between network stations and an Ethernet port that connects to a wired network (normal connection).
Function of the Working Parts The radio signal, data structure, and the network structure are the three essential elements that form the wireless internet standard 802.11 WiFi networking. Radio signals of
12 WiFi Technology 802.11b, 802.11a, and 802.11g can be received or transmitted from antennas and routers, which are known as access points, through laptops, computers, cell phones and palm pilots. The standard 802.11g radio signal is considered to be fastest and most reliable when it comes to quality compared to the other two standars. In order for computers, laptops and palm pilots to receive this wireless connection, they must be properly equipped. Meaning a WiFi card must be installed either externally or internally to the computer, laptop or palm pilots. WiFi cards come in three different types just like how there are three different WiFi WiFi standards, the 802.11 series. series. Once a successful connection has been made from the access point to the WiFi card, the user may now access the internet without any cords used. The name of the term regarding the location where one can access the internet wirelessly is called a “hotspot”. There are fee-typed and free-typed based wireless connections in Wifi. If a user is given a log on screen, when first connecting to wireless internet, it is most likely going to be a fee-typed base connection. Although there are areas where there are free-typed base as well. Wireless connection may sound reliable at times; it is very prone to hackers. They have could enter your personal computer data and implant viruses and worms into your computer. That is why people are being urge use firewall as a protection from these notorious hackers. Speaking of security, security, a WiFi connection can either be open or secure. If a secure connection exists, a user must input a WEP code in order to access the internet. People now use the 128-bit WEP encryption due to the lack of security found in the 64-bit encryption. Think of this WEP code as a password to enter a private server on the internet. Radio waves and access points work together which makes WiFi connection possible. Access points which consist of antennas and routers are the main source which transmit and receive radio waves. Antennas work stronger and have a longer radio transmission with a radius of 300-500 feet which are used in public areas while the weaker yet effective router is more suitable for homes with a radio transmission of 100-150 feet.
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FUTURE WiFi ADVANCEMENTS Bluetooth is a wireless technology that allows computers, phones and other devices to talk to each other over ov er short distances (typically about 10 meters). It is found in many of the newer mobile phones, handheld h andheld computers, and laptops as well as a s in other sorts of products. Bluetooth uses radio waves and is designed to be an inexpensive way of connecting and exchanging information between devices without wires. wires. Bluetooth can be used to exchange business cards or even used for sending voice from a headset to a mobile phone. Examples of this type type of technology are the Nokia 6600 and the Sony Ericsson P900 mobile phones. These specific phones allow you to connect your PC and enable you to transfer files files and perform backups. Some of the disadvantages to this technology are that confidential data can c an be obtained, anonymously anon ymously,, and without the owner’s consent from other other Bluetooth enabled mobile phones. This data includes not only the phonebook and an d calendar, but media files such as pictures and text messages. Most devices have and option where you can put your device into a non-discoverable state so that you are invisible to other Bluetooth devices. While in this mode all your information and data are safe. However, in order to receive business contacts wirelessly wirelessly you will need to place the phone in discoverable mode. Bluetooth is all good and well but one of the most leading technologies is Ultra-wideband (UWB) modulations. UWB usually refers to a radio modulation technique b ased on transmitting very-short-duration pulses, whereby the occupied bandwidth goes to very large values. This may also be used to refer to anything with a very large bandwidth. UWB is now going through the necessary authorizations and developments for public and commercial use. There's a possibility that this will become the the "next best" technology for all types of wireless wireless networks, including wireless wireless LANs. Because UWB operates at such low power, it has very little interference impact on other systems. Another advantage is that it could connect virtually every multimedia device in your home without using any wires. Digital cameras and camcorders could wirelessly stream images and video to your TV or and flat screen monitors could wirelessly connected to computers, DVD players, or any other source you desire. UWB will very likely revolutionize the home multimedia scene and eliminate all the tangled wires found behind home entertainment centers. A Radio Frequency Identification (RFID) tag is a small silicon microchip attached to an antenna that emits a unique serial number via radio over short distances. The RFID device serves the same purpose as a bar code or a magnetic strip on the back of a credit card or ATM ATM card; it provides a unique identifier for that object. And, just as a bar code or magnetic strip must be scanned to get the information, the RFID device must be scanned to retrieve the information. In contrast, RFID devices will work within a few feet (up to 20 feet for high-frequency devices) of the scanner. For example, you could just put all of your groceries or purchases in a bag, bag , and set the bag on the scanner. It would be able to query all of the RFID devices and total your purchase immediately. immediately. RFID tags can also be placed in living organisms to help track or identify them within short distances. distances. This is not extremely dangerous but it will need to be encased in a special kind of casing that will not irritate or react with the living tissues that it is inserted
14 WiFi Technology into. Some of the disadvantages of this technology are that they they are relatively easy to jam using energy at the right frequency. frequency. RFID tags are also difficult for consumers to remove; some are very small and others may be hidden or embedded inside a product where consumers cannot see them or get ge t to them. RFID tags can be read without your knowledge which enables others to view information information about you. These new WiFi WiFi advancements are destined to change the networking world all together. together. But we must understand that we have to take the proper precautions to make these new technologies more secure for the customers.
OVERVIEW OF MATERIAL MATERIAL 1. Which of the following is not one of the four components of Wireless Internet Access Access that help form it’s structure. a. wired PC b. networking gateway c. wireless network d. wireless customer. ANSWER = a. wired PC 2. True or False Routers Create the networks that broadcast the signal to wireless-equipped devices. ANSWER = True 3.3. What is the current security standard that most wireless customers use today. a. 802.3 b. 802.11i c. VPN d. 802.11a ANSWER = b. 802.11i 4. All of the following are an example of future WiFi advancements except:. a. Bluetooth b. RFID tags c. VoIP d. ultra-wideband modulations ANSWER = c. VoIP 5. When access points are placed where users typically gather, such as conference rooms and cafeterias, these areas are called ______. ANSWER = hot spots
BENEFITS OF WiFi
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•Freedom of Movement •Many compatible devices Continuous connection to a network from a variety of sites. •No wires = lower installation costs
Conclusion Wi-Fi offers offers tremendous potential for network connectivity without the inconvenience of wires and cables. However, for medical applications, users must take extra precautions to ensure that transmissions will be secure. For wireless LANs, implementing a VPN is currently one of the best options for securing the network; mobile workers who use Wi-Fi connections in public places should probably refrain from sending any sensitive information. This might change as the new ge nerations of Wi-Fi Wi-Fi and its accompanying security protocols are developed and approved, but for the present the technology cannot guarantee privacy. In the coming years, though, wireless transmissions will certainly evolve to the point of becoming nearly transparent in our daily work, as we seamlessly communicate with sound, pictures, and data from wherever we happen to be. For a description of how St. Vincent's Vincent's Hospital in Birmingham, Alabama has implemented a "digital hospital" employing a wide range of wireless technologies.
