Question

802.11 MAC Frame: FC -- DUR -- ADD1 -- ADD2 -- ADD3 -- SEQ -- What is the next component?

A) Address 4 (ADD4)
B) Data
C) Frame Check Sequence (FCS)
D) Frame Body

Answer 1

The next component in an 802.11 MAC frame after FC -- DUR -- ADD1 -- ADD2 -- ADD3 -- SEQ is Address 4 (ADD4), which is used in specific frame types like those in Wireless Distribution Systems or Mesh configurations.

Step-by-step explanation:

The next component after FC -- DUR -- ADD1 -- ADD2 -- ADD3 -- SEQ in an 802.11 MAC frame is Address 4 (ADD4). When constructing an 802.11 MAC frame, the fields are filled in the following order: Frame Control (FC), Duration/ID (DUR), three address fields (ADD1, ADD2, ADD3), Sequence Control (SEQ), and then, if necessary for the frame type, an additional Address field (ADD4). After ADD4, the remaining components of the frame will be the Frame Body followed by the Frame Check Sequence (FCS).

However, the Address 4 field is not present in all frame types; it is mainly used in frames involving Wireless Distribution System (WDS) or in Mesh configurations.