# WiFi - Wireless Networking ## What is WiFi WiFi is a family of wireless network protocols based on the IEEE 802.11 family of standards, which are commonly used for local area networking and internet access. WiFi allows devices such as laptops, smartphones, tablets, smart televisions, and many other devices to connect to a network wirelessly within a limited range. WiFi uses radio waves to transmit data between devices and a wireless access point or router. The term WiFi does not stand for anything specific but was coined as a marketing term. ## How WiFi Works A WiFi network is created when a router or access point broadcasts a wireless signal that nearby devices can detect and connect to. The access point is typically connected to the internet through a wired connection. Wireless devices with WiFi adapters scan for available networks and display them as a list of network names. When a user selects a network and provides the correct password, the device authenticates with the access point and receives network configuration through DHCP. The device then communicates with the access point using radio waves, and the access point forwards traffic between the wireless device and the wired network. ## WiFi Frequency Bands WiFi operates on multiple frequency bands. The 2.4 gigahertz band has longer range and better penetration through walls but lower maximum speeds and more susceptibility to interference from Bluetooth devices, microwave ovens, and other WiFi networks. The 5 gigahertz band offers higher speeds and less interference but shorter range and worse wall penetration. WiFi 6E adds support for the 6 gigahertz band, which is less congested and supports very high speeds over short distances. ## WiFi Standards The 802.11b standard introduced in 1999 achieved 11 megabits per second on the 2.4 gigahertz band. The 802.11g standard reached 54 megabits per second. The 802.11n standard, known as WiFi 4, introduced MIMO technology with multiple antennas and achieved hundreds of megabits per second. The 802.11ac standard, known as WiFi 5, achieved multi-gigabit speeds on the 5 gigahertz band. The 802.11ax standard, known as WiFi 6, improves efficiency in crowded environments using OFDMA and MU-MIMO. WiFi 6E extends WiFi 6 to the 6 gigahertz band. ## WiFi Security Securing WiFi is important because the signal extends beyond physical walls and can be received by anyone nearby. WEP was the original security protocol but was found to be easily broken and should not be used. WPA improved security. WPA2 with AES encryption was the standard for many years and remains adequate when using strong passwords. WPA3 is the current standard providing stronger security against dictionary attacks through Simultaneous Authentication of Equals.