1. Wireless Networks Mr. Howards – Quick Start Guide

2. What's a wireless network?

4. Wireless Connections To connect to a wireless network, the devices must have a wireless network card. Laptops, Tablets, Phones, Printers TV’s can easily be connected together or to a network using wireless.. The Advantages of using wireless are: – Avoid the expense, time and disruption of installing network cables – Connected devices can be moved around and as long as the device is within range it will stay connected

5. Speed of Data Transmission Wireless networks have slower rates of data transmission than wired networks. The user sees this by having to wait longer for web pages to load, files to download or upload or by seeing jerky or stuttering video playback:

6. StandardRate (bit/s)Rate (byte/s)Year Classic WaveLAN2 Mbit/s250 kB/s1988 IEEE 802.112 Mbit/s250 kB/s1997 RONJARONJA (full duplex)10 Mbit/s1.25 MB/s2001 IEEE 802.11a54 Mbit/s6.75 MB/s1999 IEEE 802.11b11 Mbit/s1.375 MB/s1999 IEEE 802.11g54 Mbit/s6.75 MB/s2003 IEEE 802.16IEEE 802.16 (WiMAX)70 Mbit/s8.75 MB/s2004 IEEE 802.11g with Super GIEEE 802.11g with Super G by Atheros108 Mbit/s13.5 MB/s2003 IEEE 802.11g with 125 High Speed ModeIEEE 802.11g with 125 High Speed Mode by Broadcom 125 Mbit/s15.625 MB/s2003 IEEE 802.11g with Nitro by Conexant140 Mbit/s17.5 MB/s2003 IEEE 802.11n600 Mbit/s75 MB/s2009 IEEE 802.11acIEEE 802.11ac (maximum theoretical speed) 6.93 Gbit/s850 MB/s2012 IEEE 802.11adIEEE 802.11ad (maximum theoretical speed) 7.138 Gbit/s900 MB/s2011

7. Check your Understanding How do we measure data transfer speed? megabit per second (symbol Mbit/s or Mb/s, often abbreviated "Mbps") is a unit of data transfer rate equal to: 1,000,000 bits per second 1,000 kilobits per secondkilobits 125,000 bytes per second (25,000 words) 125 kilobytes per second

8. Bandwidth The number of devices connected at any time and the BANDWIDTH of the connection will affect the transfer of large amounts of data over a wireless network connection. High bandwidth connections allow large amounts of data to be quickly transferred. Watching video over a wireless connection requires a high bandwidth connection Wireless connections can stop or (drop out) at the edge of their range or if there is an obstacle in the way, like a wall.

9. Bandwidth

11. Check your Understanding Why does streaming a video often pixilate when using 3G? 3G does not have a large bandwidth so the data is often not streamed ‘fast’ enough with the result that the stream cannot keep up – the image then looks pixelated or stops as data is missing.

12. Wi-Fi Wi-Fi is often used as another name for a wireless network. Public wireless networks (Wi-Fi ‘hotspots’) allow portable devices to connect to the internet. Wi-Fi hotspots can be found in cafes, hotel, libraries and many other public spaces and have a limited range from the access point.

13. SECURITY

14. (SSID) Service Set Identifier SSID is a case sensitive, 32 alphanumeric character unique identifier attached to the header of packets sent over a wireless local-area network (WLAN) that acts as a password when a mobile device tries to connect.packetsWLAN The SSID differentiates one WLAN from another, so all access points and all devices attempting to connect to a specific WLAN must use the same SSID to enable effective roaming.access points SSID is also referred to as a network name because essentially it is a name that identifies a wireless network.

15. SSID Security SSID is considered to be a fairly weak form of security because an SSID can be sniffed in plain text from a packet and most access points broadcast the SSID multiple times per second within the body of each beacon frame.sniffed

16. Security Cont…… WEP (Wired equivalent privacy) is an older attempt to secure wireless networks. WPA, WPA2 (Wi-Fi protected access) and AES (Advanced Encryption Standard) have superseded WEP as they are more secure.

17. Check Your Understanding Why is WPA2 used when connecting to a wireless network? WPA2 is a type of security that uses encryption when sending data over a wireless network. WPA2 is more secure than other types of encryption

18. Check Your Understanding Explain why using your laptop connected to a wireless network in a coffee shop to work on confidential documents is not good practice? Public wireless networks are less secure than private ones so the documents may be intercepted by unauthorised users.