A wireless network uses radio frequency (RF) waves to enable devices to communicate with each other. (unbounded media)

Wi-Fi Standards

802.11

The 802.11 standard defines both how wireless devices communicate and how to secure that communication. Wireless network cards, configuration software and ….

Hardware

Wireless Ethernet NICs take data passed down from the upper OSI layers, encapsulate it into frames, send the frames out on the network media in streams of ones and zeroes, and receive frames sent from other computing devices. This devices transmit and receive radio waves instead of pulse of light.

• 802.11 frames are not addressed and encapsulated the same way as 802.3 Ethernet frames.
• Wireless access point (WAP): Is a device designed to interconnect wireless network nodes with wired networks. a basic WAP works like a hub (Layer 1). Many of them combine multiple devices into one box switch/router (different layers).

Software

Every wireless network adapter needs 2 pieces of software to function with OS: a device driver to talk to the wireless NIC and a configuration utility.

• Link-state → To determine your wireless device is connected
• Signal strength → Measurement of how well your wireless device is connecting to other devices.

Wireless Network Modes

• 802.11 networks operates in 2 modes

Range

The maximum ranges listed in the sections that follow are those presented by wireless manufacturers as the theoretical maximum ranges. In the real word you’ll achieve these ranges only under the most ideal circumstances. (Cut the ranges in half)

• Solid objects and other wireless devices and effects ranges

BSSID, SSID, and ESSID

• The basic service set identifier (BSSID) → Defines the most basic infrastructure mode network as the same as MAC address but for the WAP.
• Ad Hoc networks don’t have WAP so the node that connect in an IBSS randomly generate a 48-bit string of numbers, that BSSID goes in every frame.