Basics of WiFi (original) (raw)

Basics of Wi-Fi

Last Updated : 28 Apr, 2026

Wireless networking technology that enables devices to connect to a local network and the Internet using radio waves instead of cables is known as Wi-Fi.

• Uses radio waves instead of physical cables for data transmission.
• Based on IEEE 802.11 standards.
• Enables wireless local area networks (WLAN) using access points.
• Supports devices like laptops, smartphones, and tablets.
• Operates at the Physical and Data Link layers of the OSI model.

Wireless access point connecting multiple devices such as smartphones, laptops, and cameras to a network.

Access Point (AP)

Acts as a wireless LAN base station that connects wireless devices to a wired network, typically the Internet, using an Access Point (AP).

• Acts as a central transmitter and receiver for wireless devices
• Allows multiple devices to connect simultaneously
• Bridges wireless users to a wired LAN
• Plays a crucial role in WLAN communication

Wi-Fi Architecture

The IEEE 802.11 architecture defines two main types of services:

1. Basic Service Set (BSS)

Known for fundamental building block of a wireless LAN.

Types of BSS:

**1.1 Infrastructure BSS

• Includes one access point
• Wireless devices communicate through the AP
• Can exchange data with other BSSs

**2.2 Independent BSS (IBSS) / Ad-hoc Network

• No access point is present
• Devices communicate directly with each other
• Cannot communicate with other BSSs
• Suitable for small, temporary networks

IBSS (ad hoc) vs BSS (infrastructure) Wi-Fi communication.

2. Extended Service Set (ESS)

Formed by connecting two or more Basic Service Sets (BSSs) through a distribution system like Ethernet, this arrangement is known as an Extended Service Set (ESS).

• Multiple BSSs are interconnected
• Each BSS has its own access point
• Allows seamless roaming between BSSs
• Used in large networks like campuses and offices

Types of Stations in ESS

• **Mobile Stations: Wireless devices within a BSS
• **Stationary Stations: Access points connected to the wired LAN

ESS with multiple access points for wider coverage.

Features of Wi-Fi

• **Wireless Connectivity: Allows devices to connect without physical cables, providing mobility and flexibility.
• **High Speed: Supports fast data transfer rates suitable for streaming, browsing, and file sharing.
• **Easy Setup: Simple to install and configure; most modern devices have built-in Wi-Fi support.
• **Multiple Device Support: Enables multiple users and devices to connect simultaneously to the same network.
• **Security: Uses encryption methods such as WPA and WPA2 to protect data from unauthorized access.
• **Range: Coverage depends on router power, environmental conditions, and physical obstacles.
• **Compatibility: Works with a wide range of devices including smartphones, laptops, tablets, and smart home devices.
• **Interference: Performance may be affected by other wireless devices and physical barriers.
• **Reliability: Network speed and stability can decrease due to congestion or weak signal strength.