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AGENDA Introduction What is IEEE 802.11 Setup required for WiFi Working of WiFi WiFi Network Topologies WiFi Security Threats WiFi Security Advantages Disadvantages Comparison B/w Wired & Wireless Network Application of WiFi
INTRODUCTION Wireless Technology is an alternative to WiredTechnology, which is commonly used, for connecting devicesin wireless mode. WiFi is a wireless technology that uses radio frequency totransmit data through the air. WiFi is a generic term that refers to the IEEE 802.11communications standard for Wireless Local Area Networks(WLANs). WiFi Network connect computers to each other, to theinternet and to the wired network. It offers peak data speeds of up to 11 Mbps.
What is IEEE 802.11IEEE 802.11 is a set of standards carrying out Wireless LocalArea Network (WLAN) computer communication in the 2.4 to5 GHz frequency bands. They are created and maintained bythe IEEE (Institute of Electrical & Electronics Engineers)Standards Committee. IEEE 802.11b IEEE 802.11a IEEE 802.11g
IEEE 802.11b Appeared in late 1999 Operates at 2.4GHz radio spectrum 4-6 Mbps (actual speed) can go up to 11 Mbps within the range of 30 m 100 -150 feet range Most popular, Least Expensive Interference from mobile phones and Bluetooth devices which can reduce the transmission speed.
IEEE 802.11a Introduced in 2001 Operates at 5 GHz radio spectrum (less popular) 15-20 Mbps (Actual speed) can go up to 54 Mbps as the range reduces 50-75 feet range More expensive Not compatible with 802.11b
IEEE 802.11g Introduced in 2003 Operates at 2.4 GHz radio spectrum 54 Mbps (Actual speed) 100-150 feet range Combines the features of both Standards i.e. IEEE 802.11b & IEEE 802.11a Compatible with 802.11b
Setup Required for WiFi ACCESS POINT Consists of a Radio Transmitter and receiveras well as an interface to a wired network or directly tothe internet Serves as a base station and a bridge betweenthe wireless network and a larger Ethernet network orthe internet.
WIRELESS CARDS Network card which connects to a radio-basedcomputer network, unlike a regular network interfacecontroller (NIC) which connects to a wire-based networksuch as Ethernet. They accept the wireless signal and relayinformation. They can be internal and external
Working of WiFi Basic concept is same as Walkie talkies A WiFi hotspot is created by installing an access point to an internetconnection An access point acts as a base station . When WiFi enabled device encounters a hotspot the device can thenconnect to that network wirelessly. A Wireless Network uses Radio Waves, just like Cell phone, Radio do.
A computer’s Wireless Adapter translates data into Radio signals andtransmit it using Antenna. A wireless router receives the signals and Decodes it. The Router sendsthe Information to the Internet. A single access point can support up to 30 users and can functionwithin a range of 100 – 150 feet indoors and up to 300 feet outdoors. Many access points can be connected to each other via Ethernet cablesto create a single large network.
AP-based topology The client communicates through Access Point. Basic Service Area-Radio Frequency coverage provided by an AP. Extended Service Area - It consists of 2 or more BSA. ESA cell includes 10-15% overlap to allow roaming.
Peer-to-peer topology Access Point is not Required. Client Devices within a cell can communicate directly with each other. It is useful for setting up of wireless network quickly and easily.
Point-to-Multipoint Bridgetopology Used to connect LAN’s b/w two or more buildings even miles apart. These conditions receive a clear line of sight b/w buildings. The line of Sight range varies based on the type ofwireless bridge and antenna used as well as theenvironment conditions.
WiFi SECURITY Threats Wireless technology doesn’t remove anyold security issues, but introduces new ones Eavesdropping Man-in-the-middle attacks Denial of Service
Eavesdropping Easy to perform, almost impossible to detect By default, everything is transmitted in clear text Usernames, passwords, content ... No security offered by the transmission medium Different tools available on the internet Network sniffers, protocol analysers . . . Password collectors With the right equipment, it’s possible to eavesdrop traffic from few kilometers away
Man In The Middle Attack Attacker spoofes a disassociate message from the victim The victim starts to look for a new access point, and the attacker advertises his own AP on a different channel, using the real AP’s MAC address The attacker connects to the real AP using victim’s MAC address
Denial of Service Attack on transmission frequecy used Frequency jamming Not very technical, but works Attack on MAC layer Spoofed deauthentication / disassociation messages can target one specific user Attacks on higher layer protocol (TCP/IP protocol) SYN Flooding
WiFi SECURITYThe requirements for WiFi network security consists of anprimary component i.e. : Authentication User Authentication Server Authentication
AuthenticationKeeping unauthorized users off the network User Authentication Authentication Server is used Done using Username and password of the User Risk: Data (username & password) send before secure channel established Prone to passive eavesdropping by attacker Solution: Establishing a encrypted channel before sending username and password
Server Authentication Digital Certificate is used Validation of digital certificate occurs automatically within client software
Advantages Flexible Working: Access the Internet, do File Transfers, even Print from anywhere within 100meters of the WiFi Access Point. Reduce Cable Clutter: Reduce the clutter of wires and cables behind your Desktop/ Notebook Reduce Setup Cost: Save the cost of cabling and the cost on Network sockets Avoid Deterioration with Time: Network Cables and Sockets tend to deteriorate over time, while WiFi doesnot have this disadvantage Eliminate Re-configuring Computers: Can Access WiFi at two different locations under the same company’snetwork without having to re-configure their Internet settings each time.
Disadvantages Password and Security: It is important to secure your WiFi connection at home or the office. Otherwise,anyone with a WiFi enabled computer can access your data and Internet connection!Password-protecting your WiFi connection is an easy process and once you set up allyour Computers and devices to access your WiFi network, you do not need to type inpasswords each time thereafter. Signal Strength Sensitivity: WiFi Networks are sensitive to signal strength. To ensure good connectivity,you must ensure that all computers and gadgets receive adequate signal strength Effect of Climatic Conditions: WiFi signals are likely to be adversely affected by climatic conditions such asthunderstorms. Increased number of Network Devices: You are increasing the number of devices on your Network, by incorporating aWiFi Access point. Also, you will need a power socket to plug in and power the WiFiAccess Point.
Comparison B/w Wired &Wireless NetworkFeatures Wired Home Network Wireless Home networks The networking of the wired The networking of theNetworking home networks are more wireless networking is good faster as compared to other and better for the future types of wireless networking resources but it is not faster devices because they are as the wired home able to provide the speed of networking devices. Wifi is more then 1000 Mbps the common types of wireless home network that can provide the reliable workingCost Comparison We need many expenses to As compared to other wired configure or setup the wired devices it is easy to setup the home network. Because we wireless networking devices need large money to spread at the very low and at the the network of coaxial reliable cost cables.
Comparison B/w Wired &Wireless Network . . . Contd… Features Wired Home Network Wireless Home networks Advantages More reliable You can Access internet Faster internet from any place through hot Transfer of data at a very pots faster speed No hassles of cables No need any kind of wiring for installation Cons It can not provide mobile Not very much reliable network Only best for mobile Difficult to lay down the devices such as Laptops cables and it looks very Not faster as compared to messy when install outside wired devices
Application of WiFi Sharing of Files: Sharing and Exchanging of Data can take place with nearby Computers in theNetwork. Accessing the Internet: Using the WiFi, Internet can be made available to the Computers connected tothe Network. Stream Audio to Wireless Speakers: One of the useful application of WiFi is that using it one can Stream audio toaudio devices present in the Network Area that are compatible to it. Device Sharing: Similar to Wired Network WiFi provides the feature to access the Devices beingshared within the Network. Like one can command the Printer attached to anySystem in the network and get their documents print.