Free The data link layer lessonsThe data link layer · Stage 0 · Detecting and fixing errors · Step 1
Parity and checksums
Add a little redundancy to a frame so the receiver can tell when bits have been damaged. About 12 minutes.
Even parity is used on a word and exactly two of its bits are flipped in transit. What does the receiver conclude?
- AThe word looks correct, because the count of 1s is still even
- BThere is an error, but it can't tell where
- CIt finds and corrects both bits
Show the answer
The word looks correct, because the count of 1s is still even. Parity only notices an odd number of flipped bits.
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