WLAN

A wireless local area network (WLAN) connects devices across a limited area using radio communication rather than requiring a cable to every endpoint. Most modern WLANs use the IEEE 802.11 family of technologies commonly called Wi-Fi.

Motivation

Wired local networks provide stable and predictable links, but cables restrict mobility and can be difficult to install. WLANs let laptops, phones, sensors, and other devices join a local network while moving within a home, office, campus, or public venue.

Where it fits

A WLAN usually provides link-layer access to the same broader IP network that wired Ethernet devices use. An access point bridges wireless clients to a distribution network, while routers connect that local network to other networks.

Mental model

Think of a WLAN as a shared radio-based access medium:

1. An access point advertises a network identity, usually an SSID.
2. A client discovers and authenticates to that network.
3. The client and access point exchange link-layer frames over a radio channel.
4. The access point bridges or forwards traffic toward the rest of the local network.

Core ideas

• Access point: Coordinates wireless access and connects clients to the distribution network.
• SSID: A human-visible identifier for a wireless network; it is not itself a security boundary.
• Channel and frequency band: WLANs share limited radio spectrum, so interference and channel planning affect performance.
• Association and authentication: A device must join the network and, for protected networks, prove that it is authorized.
• Encryption: Modern deployments use protections such as WPA2 or WPA3 to secure traffic over the radio link.
• Roaming: Multiple access points can provide one logical network so clients can move between coverage areas.

WLAN versus Wi-Fi

WLAN is the general network category. Wi-Fi is the dominant certification and technology ecosystem based on IEEE 802.11. In everyday use the terms are often treated as synonyms, but a WLAN describes the network while Wi-Fi describes the technology commonly used to implement it.

Tradeoffs

WLANs improve mobility and deployment flexibility, but radio links are shared and variable. Walls, distance, interference, client density, authentication design, and access-point placement can affect capacity, latency, and reliability.

Common mistakes

• Assuming strong signal strength guarantees high throughput.
• Treating an SSID as a security mechanism.
• Adding more access points without coordinating channels and transmit power.
• Confusing the wireless link with the internet connection behind it.
• Comparing advertised radio rates directly with application throughput.

Related concepts

WLAN connects to Ethernet, network interfaces, packets, routers, link-layer protocols, authentication, and encryption.