Wireless Ethernet

Overview

Wireless Ethernet (also called Wi-Fi) allows workstations to connect to a network as long as they are within the range of an access point.
Various versions of the IEEE 802.11 standard define different wireless LAN connections.
Collisions for communication is done using Wireless CSMA CA
Some problems of wireless ethernet are Hidden Terminal Problem and Exposed Terminal Problem
WLAN Frequency Planning is used to manage radio waves.

Basic Components

Client Radio: Typically a PC card with an integrated antenna, installed in laptops or workstations.
Access Point (AP): Contains an Ethernet port and a transceiver. The AP acts as a bridge between wired and wireless networks and can perform basic routing functions.

Service Sets

Basic Service Set (BSS): Workstations with client radio cards within the range of a single access point.
Extended Service Set (ESS): Multiple Basic Service Sets interconnected to form a larger network.

Frequency Bands

ISM Band: Includes 900 MHz, 2.4 GHz, and 5 GHz frequencies used for wireless communication.

IEEE 802.11 Standards

Standard	Release Year	Maximum Data Rate	Frequency Bands	Description
802.11	1997	2 Mbps	2.4 GHz	The original wireless standard.
802.11b	1999	11 Mbps	2.4 GHz	Known as Wi-Fi. Improved data rate over 802.11. With directional antennas, can reach up to 16 km; typically 100 feet (30 m) with omni-directional antennas.
802.11a	2002	54 Mbps	5 GHz	Faster standard with a higher frequency, providing less interference. Max transmission distance of 90 feet (27 m).
802.11g	2002	54 Mbps	2.4 GHz	Operates on the same frequency as 802.11b but with higher data rates. Backwards compatible with 802.11b.
802.11n	2009	600 Mbps (theoretical)	2.4 GHz, 5 GHz	Uses MIMO technology for higher data rates and improved reception. Actual data rates range from 100 to 145 Mbps.
802.11ac	2013	1.3 Gbps (theoretical)	5 GHz	Also known as Wi-Fi 5. Supports wider channels and higher data rates with improved MIMO technology.
802.11ax	2019	9.6 Gbps (theoretical)	2.4 GHz, 5 GHz, 6 GHz	Known as Wi-Fi 6. Introduces higher data rates, improved efficiency, and better performance in dense environments. Supports the 6 GHz band in addition to 2.4 GHz and 5 GHz.

Summary

IEEE 802.11 standards have evolved from basic data rates and limited frequency bands to advanced technologies offering higher data rates, improved efficiency, and greater coverage.
Wi-Fi 6 (802.11ax) represents the latest advancement, enhancing performance and efficiency, especially in crowded network environments.