Frame check sequence

The term frame check sequence (BPF ) or English Frame Check Sequence (FCS ) indicates a checksum for a data block (frame) of a network protocol is added to enable error detection (including error correction on layer 2 ). Usually a Cyclic Redundancy Check (CRC) (Eng. Cyclic Redundancy Check ) is used with 16-bit.

The transmitter calculates the checksum for the entire block of data, and this depends on the rear of the block. The receiver also calculates the checksum of the block and compares it to the sent along FCS. For calculating the same algorithm is used on both sides. If the test fails, the block is discarded by the receiver.

Error detection and error correction methods which are based on a FCS, the data link layer ( Layer 2 / Layer 2) of the OSI model are attributable.