The Frame Check Sequence (FCS) is a 4-byte field at the end of each 802.11 data frame. It contains a 32-bit cyclic redundancy check (CRC) that is used to detect errors in the frame.
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Introduction
The Frame Check Sequence (FCS) is a 4-byte CRC field located at the end of each 802.11 data frame. The FCS is used to ensure that no errors have occurred during the transmission of the data frame. If the FCS is incorrect, the data frame will be discarded by the receiving station.
The Size of the Frame Check Sequence Field in an 802.11 Data
The size of the frame check sequence (FCS) field in an 802.11 data frame is artistically chosen to be 4 bytes, or 32 bits. The FCS is generally not visible to users, as it is automatically generated and checked by NICs and access points. The FCS field contains a 32-bit Cyclic Redundancy Check (CRC) value that is used to check for frame integrity.
Conclusion
The frame check sequence (FCS) is a field used in Ethernet and other computer network technologies. It is used to store a mathematical checksum of the data in the frame. The FCS is sometimes called a trailer because it comes after the main data body in the frame.
The FCS is used to detect errors in the transmission of data frames. If the FCS field contains an incorrect value, it means that the data in the frame has been corrupted and the frame will be discarded.
The size of the FCS field is 4 bytes.
