Primary definition
A symmetric key cryptographic algorithm that transforms a block of information at a time using a cryptographic key. For a block cipher algorithm, the length of the input block is the same as the length of the output block. (SP 800-90) (NISTIR)
Also known asblock encryption algorithm · block encryption cipher · block cipher algorithm
1 sources cited4 related termsReviewed Aug 10, 2026
— The Cyber GlossaryView source
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TCG
A symmetric key cryptographic algorithm that transforms a block of information at a time using a cryptographic key. For a block cipher algorithm, the length of the input block is the same as the length of the output block. (SP 800-90) (NISTIR)
The Cyber Glossary · 2024
Cite this term
Permanent URL · stable across revisions
Election Security Glossary. (2026). Block Cipher. In Election Security Glossary. Retrieved August 21, 2026, from https://electionsecurityglossary.com/glossary/block-cipher
Sources
1 cited · last checked Aug 10, 2026
01
The Cyber Glossary
The Cyber Glossary
Single-source
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