ERROR DETECTION & CORRECTION

ERROR DETECTION & CORRECTION

1. type error

   • single-bit error
   • burst error

2. block coding

   • error detection process
   • error correction process

3. linear block coding

4. parity-check coding

   • simple parity check
   • two-dimensional parity check

5. cyclic coding

   • cyclic redundancy check (CRC)
   • advantage
     • detect all burst errors that affect an odd number of bits
     • detect all burst errors of length less than or equal to the degree of the polynomial

6. checksum - higher level protocols

   • advantage - detect all errors involving an odd number of bits as well as most errors involving an even number of bits
   • disadvantage - cannot detect error when one or more bits of a segment are damage and the corresponding bit or bits of opposite value in a second segment are also damage