Check the Parity — TechKnowSurge

About this interactive

Integrity means data is accurate and unchanged. This lesson's checks find out whether it has changed. Making a copy is the simplest check: if the two copies still match, nothing has changed. It costs twice the storage. A parity bit costs one extra bit per block. With even parity, count the 1s in the byte. If the count is even, the parity bit is 0; if it is odd, the parity bit is 1, so that the total, data and parity bit together, is always even. When a byte arrives, count all nine bits again: an odd total means a bit has flipped and the check has found an error. A hashing algorithm turns data into a fingerprint. Change even one bit of the data and the fingerprint comes out completely different. Save the fingerprint, and later hash the data again: the same fingerprint means unchanged, a different one means changed.

What you'll learn

Work out the even parity bit for a byte, and use a received byte's parity bit to tell whether the check finds an error
Compare two fingerprints or two copies to tell whether data has changed

Aligned to

CompTIA Tech+

6.1 Summarize confidentiality, integrity, and availability concerns.

1.4 Explain the value of data and information.

CompTIA Server+

3.1 Summarize data security concepts.

Key terms

Parity Bit: An extra bit added to a block of data that makes the total number of ones either even or odd, used to detect single-bit errors in data.
Hashing Algorithm: A process that transforms input data into a unique fixed-size fingerprint, enabling detection of any change to the original data.
Data Integrity: The assurance that data has not been altered or corrupted during storage or transmission.

Topics

Parity Bit Hashing Algorithm Data Integrity Integrity Interactive Fill In

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