Wifi overview
Standards Organizations
Many manufacturer create devices
Standards must be created and adhered to in order to assure seamless operability
IEEE
Name: Institute of Electrical & Electronics Engineers
Who: The professional society who creates and maintains standards for diff technologies including network, that we use
Purpose: Creates & sets standards for betterment of humanity
Special Mention: 802.11 group was responisble for creating the Wireless LAN (WLAN) standard
IETF
Name: Internet Engineering Task Force
Who: International community of people in networking industry
Purpose: produce technical docs about design, use, & management of internet
Wi-Fi Alliance
Name: Wireless Ethernet Compatibility Alliance (WECA) - 1999, later Wi-Fi Alliance
Purpose: Compliance enforcement body by ensuring interoperability of WLAN products via certification testing
Who: In 1999, Aironet (aquired by Cisco), Nokia, Symbol Technologies (now Motorola), and 3 others formed WECA
Standards
802.11
Creator: IEEE
Maintainer: IEEE
What: Standard for WLAN communication (LAN communication using radio frequency [RF])
Why: To set one single way to achieve it - as there are many ways
Who: 400 active members, 200 wireless companies - can make suggestions
How
1997
included only transmission types FHSS & DSSS
2.4 GHz band
Speed: 1-2 Mbps
802.11a
How
1999 (same year as .11b)
5 GHz
54 Mbps (but much less range than 11b)
High cost & shorter distance
802.11b
How
1999 (same year as .11a)
2.4 GHz
11 Mbps (but much more range than 11a)
did better in market w.r.t 11a
802.11g
How
2003
2.4 GHz
54 Mbps
Compatible with 802.11b
802.11n
How
2009
2.4 & 5 GHz
Introduced MIMO - Multiple input, multiple output
channel aggregation
multiple antennas
600 Mbps (theoritical)
Compatible with 802.11b
802.11ac
How
2014
5 GHz
Enhanced MIMO - Multiple input, multiple output
extended channel bandwidth (11n's 40 MHz) to 80 MHz
increased MIMO functionality & capability
7 Gbps (theoritical)
Utilizes Beanforming as core part of the Special
Detects devices and intensify signal in their direction
This compensates for shorter range limitations of 5 GHz band
802.3
Creator: IEEE
Maintainer: IEEE
What: Standard for LAN communication (LAN communication using wired network / ethernet cable)
Regulatory Bodies
Why: WiFi is based on radio frequency. There are multiple frequencies available under RF spectrum. Using frequencies at will would eventually disable all communication.
Purpose: To keep the RF spectrum organized and open for fair use
ITU-R
International Telecommunication Union Radiocommunication sector
Regions covered:
Europe, Africa, Northern Asia
North & South America
Southern Asia
Make sure RF signal from one country do not interefer with signals of another country
FCC
Federal Communications Commission
Regulates
RF frequencies
channels
transmission power
In: United States and several countries in the America
www.fcc.gov
ETSI
European Telecommunication Standards Institute
European counterpart to the FCC