Understanding WLAN Standards and the Difference Between Wi-Fi and WLAN

Common WLAN Protocols

802.11a: Introduced in 1999, this standard is primarily used in the United States but did not gain widespread acceptance in Europe due to certain limitations. It operates in the 5 GHz band, achieving speeds up to 54 Mbps. Because the 5 GHz frequency is also used by military and aviation, 802.11a devices in Europe are restricted to indoor use with a maximum transmission power of 30 milliwatts. Additionally, 802.11a is incompatible with the more common b, g, and n standards.

802.11b: Also adopted in 1999, this standard uses the 2.4 GHz band and offers a range of up to 20 meters, although this can vary depending on environmental factors. The theoretical maximum transfer rate is 11 Mbps, but practical speeds are closer to 5 Mbps. This frequency can experience interference from other devices like microwaves and Bluetooth. Due to its slower speeds, 802.11b was quickly succeeded by faster standards.

802.11g: Launched in 2003, this standard is backward compatible with 802.11b. It also operates in the 2.4 GHz band, but with speeds up to 54 Mbps, though the practical rate is around 25 Mbps. The range is between 25 and 50 meters. However, like 802.11b, it can suffer from interference from other 2.4 GHz devices.

802.11n: Approved in 2009, this standard operates in both the 2.4 GHz and 5 GHz bands and achieves speeds up to 600 Mbps using Multiple Input Multiple Output (MIMO) technology, which employs multiple antennas to enhance data throughput. It is also backward compatible with b and g standards.

802.11ac: Released in 2014, this standard builds on 802.11n and significantly boosts performance in the 5 GHz band. Enhanced MIMO technology allows the use of up to eight antenna pairs, supporting speeds over 1 Gbps.

802.11ax: Known as Wi-Fi 6, this standard was introduced in 2019 and operates in both the 2.4 GHz and 5 GHz bands, achieving speeds over 3 Gbps. Since 2018, to simplify identification, standards are also referred to by their version numbers, with 802.11ax labeled as Wi-Fi 6 and 802.11ac as Wi-Fi 5.

Backward Compatibility

Devices that support newer WLAN standards typically maintain compatibility with older standards, provided they operate on the same frequency bands. This backward compatibility ensures that current WLAN-capable devices will remain functional for an extended period.

Difference Between Wi-Fi and WLAN

Many people use the terms Wi-Fi and WLAN interchangeably, but they technically refer to different concepts.

WLAN

WLAN stands for Wireless Local Area Network. It refers to any network that transmits data wirelessly over radio waves within a localized area, such as a building or campus. WLAN encompasses the entire network infrastructure, wireless technology, and protocols used for wireless communication.

Wi-Fi

Wi-Fi is a brand of the Wi-Fi Alliance and stands for Wireless Fidelity. It is a specific standard for wireless networks based on IEEE 802.11 standards. The Wi-Fi Alliance certifies devices that meet these standards to ensure they are compatible and can reliably communicate with each other. A device labeled as "WiFi-certified" has received this certification and can be used in a WLAN.

Summary

• WLAN is the general term for wireless local area networks, regardless of the specific standards or brands used.
• Wi-Fi is a specific brand and certification standard by the Wi-Fi Alliance, based on IEEE 802.11 standards.

Example

A WLAN can use various wireless standards, such as Bluetooth or Zigbee, not just Wi-Fi. However, when we refer to Wi-Fi, we specifically mean networks that use IEEE 802.11 standards and are certified by the Wi-Fi Alliance.

In summary: All Wi-Fi networks are WLANs, but not all WLANs are Wi-Fi networks.

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