Frames that are part of the control frames are RTS and CTS. Those two frames are used for avoiding collisions during transmitting. The client needs to be enabled for RTS/CTS. The RTS frame is sent by the client to request to send data. The CTS tells the client that the client is clear to send …

Authentication/Deauthentication Frames To enter the authentication state (remember the different states a client can be assigned to) you need authentication frames. There are four frames during the authentication. First the client transmits an authentication frame and the access point replies with an acknowledgement and an authentication (response) frame. The client replies with an acknowledgement. The …

Management frames are the frames that are used for managing the wireless LAN. In this blog, I want to write out which frames there are and what their purposes are. Beacon Frames Beacon frames have the information about the wireless network and are sent by the access point. Every 100 Time Unit is a beacon …

In the MAC header, there is also a field that is called the QoS control field, and it has different flags. It is in total a 2-byte field (16 bits). Those 16 bits are written down as followed. The first 4 bits is the Traffic Identifier. This identifies the User Priority. The User Priority is …

In the MAC header is a Frame Control field that is in total 2 bytes, so it has in total 16 bits. Those bits are defined as follows: Protocol Version, this is the version of the 802.11. In the wired network, there are two different versions at this moment. Version 4 and 6 (IPv4 and …

Frame Format Wireless Frames are a little bit different than the Ethernet frames. The Ethernet frame starts with a “preamble” and a “Start-of-Frame Delimiter (SFD).” This is the PHY frame—the wireless frame has this as well, but it is more complex. In this blog, I want to explain the MAC frame. The MAC frame in …