Error Detection EDC=Error Detection and Correction bits(redundancy) D Data protected by error checking,may include header fields Error detection not 100%reliable! protocol may miss some errors,but rarely larger EDC field yields better detection and correction 个 datagram datagram Y all bits in D N OK detected error ←dd归ta bits D EDC EDC bit-error prone link 5:DataLink Layer 5-10 5: DataLink Layer 5-10 Error Detection EDC= Error Detection and Correction bits (redundancy) D = Data protected by error checking, may include header fields • Error detection not 100% reliable! • protocol may miss some errors, but rarely • larger EDC field yields better detection and correction