Wireless network Project Class 12
- 1. WIRELESS COMPUTER NETWORK Created by : Rishabh Rawat Class XII
- 2. WIRELESS NETWORK Wireless network is a technology which enables people to communicate and access applications and information without wires. This provides freedom of movement and the ability to extend applications to different parts of a building, city, or nearly anywhere in the world from a location that they prefer. Many types of wireless communication systems exist that takes place between devices such as personal digital assistants (PDAs), laptops, personal computers (PCs), servers, and printers. Eventually, most electronics offer wireless network connections. The information can take the form of e-mail messages, web pages, database records, streaming video or voice.
- 3. Types of Wireless Networks WLANS : Wireless Local Area Networks allow users in a local area, such as a university campus or library, to form a network or gain access to the internet. A temporary network can be formed by a small number of users without the need of an access point; given that they do not need access to network resources. WPANS: Wireless Personal Area Networks :The two current technologies for wireless personal area networks are Infra Red (IR) and Bluetooth (IEEE 802.15). These will allow the connectivity of personal devices within an area of about 30 feet. However, IR requires a direct line of site and the range is less.
- 4. Types of Wireless Networks WMANS: Wireless Metropolitan Area Networks: This technology allows the connection of multiple networks in a metropolitan area such as different buildings in a city, which can be an alternative or backup to laying copper or fibre cabling. WWANS: Wireless Wide Area Networks: These types of networks can be maintained over large areas, such as cities or countries, via multiple satellite systems or antenna sites looked after by an ISP. These types of systems are referred to as 2G (2nd Generation) systems.
- 5. TRANSMISSION METHODS 1. 802.1x EAP The Extensible Authentication Protocol (EAP) is a layer 2 process that allows a wireless client to authenticate to the network. There are two varieties of EAP: one for wireless and one for LAN connections, commonly called EAP over LAN (EAPoL). One of the concerns in wireless is allowing a WLAN client to communicate to devices behind an AP. Three standards define this process: EAP, 802.1x, and Remote Authentication Dial In User Service (RADIUS). EAP defines a standard way of encapsulating authentication information, such as a username and password or a digital certificate that the AP can use to authenticate the user.802.1x and RADIUS define how to packetize the EAP information to move it across the network.
- 6. TRANSMISSION METHODS 2. WPA Wi-Fi Protected Access (WPA) was designed by the Wi-Fi Alliance as a temporary security solution to provide for the use of 802.1x and enhancements in the use of WEP until the 802.11i standard would be ratified. WPA can operate in two modes: personal and enterprise mode. Personal mode was designed for home or SOHO usage. A pre-shared key is used for authentication, requiring you to configure the same key on the clients and the AP. With this mode, no authentication server is necessary as it is in the official 802.1 x standards. Enterprise mode is meant for large companies, where an authentication server will centralize the authentication credentials of the clients.
- 7. TRANSMISSION METHODS 3. WPA2 WPA2 is the IEEE 802.11i implementation from the Wi-Fi Alliance. Instead of using WEP, which uses the weak RC4 encryption algorithm, the much more secure Advanced Encryption Standard (AES)–counter mode CBC-MAC Protocol (CCMP) algorithm is used. 4. Infrared Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than that of visible light, but shorter than that of microwave radiation. The name means "below red" (from the Latin infra, "below"), red being the color of visible light of longest wavelength.
- 8. TRANSMISSION METHODS 5. Bluetooth Bluetooth is an industrial specification for wireless personal area networks (PANs). Bluetooth provides a way to connect and exchange information between devices like personal digital assistants (PDAs), mobile phones, laptops, PCs, printers and digital cameras via a secure, low-cost, globally available short range radio frequency. The range of Bluetooth is 33 feet for class 2 Bluetooth (most Bluetooth and headphones are common class 2 devices). Class 1 Bluetooth provides a range of 328 feet.
- 9. TRANSMISSION METHODS 6. FHSS Frequency-hopping spread spectrum is a spread-spectrum method of transmitting radio signals by rapidly switching a carrier among many frequency channels, using a pseudorandom sequence known to both transmitter and receiver making it highly resistant to noise and interference. Bandwidth can be utilized more efficiently. Signals are difficult to intercept. A Frequency-Hop spread-spectrum signal sounds like a momentary noise burst or simply an increase in the background noise for short Frequency-Hop codes on any narrowband receiver except a Frequency-Hop spread-spectrum receiver using the exact same channel sequence as was used by the transmitter.
- 10. TRANSMISSION METHODS 7. DSSS Direct-sequence spread spectrum is a modulation technique where the transmitted signal takes up more bandwidth than the information signal that is being modulated, which is the reason that it is called spread spectrum. DSSS uses one channel to send data across all frequencies within that channel. Complementary Code Keying (CCK) is a method for encoding transmissions for higher data rates, such as 5.5 and 11 Mbps, but it still allows backward compatibility with the original 802.11 standard, which supports only 1 and 2 Mbps speeds. 802.11b and 802.11g support this transmission method.
- 11. TRANSMISSION METHODS 8. OFDM Orthogonal frequency-division multiplexing, also called discrete multitoned modulation (DMT), is a transmission technique based upon the idea of frequency-division multiplexing (FDM). OFDM increases data rates by using a spread spectrum: modulation. 802.11a and 802.11g support this transmission method. Used in some wireless LAN applications, including WiMAX and IEEE 802.11a/g Used in many communications systems such as: ADSL, Wireless LAN, Digital audio broadcasting.
- 12. RANGE AND SPEED The layout of the building can reduce the range as well as speed. A lot of concrete walls can reduce the range. The size of the antenna and the placement greatly affect the range of their signals. The weather and amount of water vapour in the air can affect the signals strength and range. The size of the antenna and its signal can affect your speed
- 13. Advantages of a Wireless Network The main advantage of a wireless network over a wired one is that users can move around freely within the area of the network with their laptops, handheld devices etc. and get an internet connection. Users are also able to share files and other resources with other devices that are connected to the network without having to be cabled to a port. Not having to lay lots of cables and put them through walls etc. can be a considerable advantage in terms of time and expense. It also makes it easier to add extra devices to the network, as no new cabling is needed. Wireless networks can sometimes handle a larger amount of users because they are not limited by a specific number of connection ports.
- 14. Disadvantages of a Wireless Network It can require extra costs and equipment to set up, although increasingly routers have built-in wireless capability, as do devices such as laptops, handheld devices, modern DVD players, and TVs. Setting up a wireless network can sometimes be difficult for people who are not experienced with computers. File-sharing transfer speeds are normally slower with wireless networks than they are with cabled. The speeds can also vary considerably according to your location in relation to the network.
- 15. THANK YOU…