Error Detecting Codes IF WE ARE CONCERNED THAT THE INFORMATION THAT WE TRANSMIT OR STORE IN BINARY MIGHT BE "DAMAGED" WE MIGHT PREFER CODES THAT LET US NOTICE THE DAMAGE. TO SOME DEGREE, THE BCD CODE HAS THIS PROPERTY: Digits BCD 01100001 61 01101011 ?? THE SEQUENCE OF BITS 01101011 HAS NO VALID MEANING IN BCD BECAUSE 1011binary = 11decimal WHICH CAN'T BE A SINGLE DIGIT OF A DECIMAL NUMBER. ANY CODE THAT LETS US DETECT ERRORS MUST HAVE SOME COMBINATIONS OF 0's AND 1's THAT ARE MEANINGLESS.

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This page is part of a section of lecture slides related to " Error Detecting Codes " within the topic "Data Delivery Obstacles". Other slides within this section and other sections of slides for the topic "Data Delivery Obstacles" can be accessed using the links below. Retransmission Techniques Acknowledgements and Retransmission Retransmissions and Timeouts Sequence Numbers Sequence Numbers (cont.) Message Reordering Reliability and Connections A Reliable Delivery Problem Cautious Generals Solving the General's Problem Solving the General's Problem (cont.) Connections Establishing Connections Persistent HTTP Connections Network Congestion Packet Loss and Congestion Congestion and Transmission Rate Congestion and TCP Connections Finding the Bottleneck Rate TCP Transmission Rate Adjustment Error Detecting Codes Damagaged Data Symbols and Meaning Interpreting Binary Symbols Evaluating Codes Error Detecting Codes Parity Codes for Error Detection Multiple Bit Errors Interleaved Transmission Error Correcting Codes Any Guesses? Digital Recording on Compact Discs Two-dimensional Parity Bits Spatial Interleaving