The 802.11 standards, established by the Institute of Electrical and Electronics Engineers (IEEE), define the specifications for implementing wireless local area networking (WLAN) communication. These standards govern the protocols used for wireless communication between devices such as computers, smartphones, and routers.
Overview of the key 802.11 standards:
802.11: The original standard, released in 1997, operated in the 2.4 GHz frequency band and provided a maximum data rate of 2 Mbps using frequency hopping spread spectrum (FHSS) or direct-sequence spread spectrum (DSSS) modulation.
802.11a: Ratified in 1999, 802.11a operates in the 5 GHz frequency band and supports data rates up to 54 Mbps. It uses orthogonal frequency-division multiplexing (OFDM) for more efficient data transmission.
802.11b: Also ratified in 1999, 802.11b operates in the 2.4 GHz frequency band and provides data rates up to 11 Mbps. It uses DSSS modulation and is backward compatible with 802.11.
802.11g: Introduced in 2003, 802.11g operates in the 2.4 GHz band and supports data rates up to 54 Mbps. It uses OFDM modulation and maintains backward compatibility with 802.11b.
802.11n: Ratified in 2009, 802.11n operates in both the 2.4 GHz and 5 GHz bands, offering significantly improved data rates (up to 600 Mbps or more). It introduced multiple-input, multiple-output (MIMO) technology, enhancing signal reliability and throughput.
802.11ac: Released in 2013, 802.11ac operates exclusively in the 5 GHz band and delivers higher data rates, potentially reaching gigabit speeds. It utilizes wider channel bandwidths and more advanced MIMO configurations, providing improved performance in crowded environments.
802.11ax (Wi-Fi 6): Ratified in 2019, 802.11ax is designed to improve overall network efficiency, especially in high-density environments. It operates in both 2.4 GHz and 5 GHz bands, supports OFDMA (Orthogonal Frequency-Division Multiple Access), and introduces other features to enhance performance and reduce latency.
802.11ay: This standard, still in development as of my knowledge cutoff in January 2022, is expected to operate in the 60 GHz frequency band and is intended to provide very high data rates, suitable for applications like high-speed data transfer and augmented reality.
It’s important to note that each new 802.11 standard typically builds upon the capabilities of its predecessors, introducing improvements in data rates, range, and overall performance to meet the evolving demands of wireless communication. When setting up a wireless network, it’s advisable to choose devices that support the latest standard for optimal performance and compatibility.
The following table distinguishes the differences and similarities between these standards and Bluetooth. Bluetooth is an alternative wireless network technology that followed a different development path than the 802.11 family of standards.
| 802.11 Wireless LAN Standards Comparison | ||||||
|---|---|---|---|---|---|---|
| Properties | 802.11a | 802.11b | 802.11g | 802.11n | 802.11ac | Bluetooth |
| Data Rate(Mbps) | 54Mbps | 11Mbps | 54Mbps | Up to 600 | 1.3Gbps | 721Kbps 56Kbps |
| Operating Frequency(GHz) | 5GHz | 2.4GHz | 2.4GHz | 2.5GHz 5G Hz | 5GHz | 2.4GHz |
| Typical power output (mW) | 40-800 mW | 50 to 200 mW | 50 to 200 mW | 50 to 200 mW | 50 to 200 mW | Class 1: 100 mW Class 2 1 mW |
| Compatibility | Not compatible with 802.11b or 802.11g | Not compatible with 802.11a or 802.11g | Compatible with 802.11b | 802.11b/g (2.4GHz) 802.11a (5GHz) | Not compatible with 802.11a/b. | |
| Range | 150feet | 150feet | 150feet | 150ft | 150ft | 30feet |
| Interference risk | Low | High | High | High | High | High |
| Price | Expensive | Cheap | Moderate | moderate | high | Moderate |
| Hot-spot access | Poor | Good | Good | Good | Good | Poor |
Though 802.11a and 802.11b standards have been developed around the same time, 802.11b has become very popular due affordability of the hardware for small business and home networking. However, considering any future expansion, it is desirable to buy equipment that is capable of operating in duel modes (802.11 a/b).
Bluetooth supports a very short range (approximately 10 meters) and relatively low bandwidth (1 Mbps). In practice, Bluetooth networks PDAs or cell phones with PCs but not used widely for general-purpose Wireless LAN networking. The very low manufacturing cost of Bluetooth makes it a viable solution for wireless devices like PDAs and Cell phones. Note that the 801.11 and Bluetooth standards are incompatible with each other.