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CITS3002 Computer Networks |
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Some Standard Polynomial Codes16 bit checksums catch -
CRC-12 = x 12 + x 11 + x 3 + x 2 + x + 1 CRC-16 = x 16 + x 15 + x 2 + 1 CRC-CCITT = x 16 + x 12 + x 5 + 1 CRC-32 = x 32 + x 26 + x 23 + x 22 + x 16 + x 12 + x 11 + x 10 + x 8 + x 7 + x 5 + x 4 + x 2 + x + 1 CRCs are often performed in hardware, for example the DEC-VAX architecture (mid-1980s) had an assembly language instruction to perform CRC-16 (!). Today, all network interface cards (such as wired and wireless Ethernet) perform checksumming "on-board".
CITS3002 Computer Networks, Lecture 2, The Physical Layer, Errors detection and correction, p17, 6th March 2024.
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