block cipher

{
  "id": "MLC-T-CYB-000475",
  "term": "block cipher",
  "field": "Cybersecurity",
  "definition": "1. A family of permutations of blocks that is parameterized by the key.\n\n2. A family of functions and their inverse functions that is parameterized by cryptographic keys; the functions map bit strings of a fixed length to bit strings of the same length.\n\n3. An invertible symmetric-key cryptographic algorithm that operates on fixed-length blocks of input using a secret key and an unvarying transformation algorithm. The resulting output block is the same length as the input block.\n\n4. An algorithm for a parameterized family of permutations on bit strings of a fixed length.\n\n5. A parameterized family of permutations on bit strings of a fixed length; the parameter that determines the permutation is a bit string called the key.\n\n6. A symmetric-key cryptographic algorithm that transforms one 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.",
  "references": [
    "FIPS 197 [NIST FIPS 197-upd1]",
    "NIST IR 8459; NIST SP 800-135 Rev. 1; NIST SP 800-38A",
    "NIST SP 800-107 Rev. 1",
    "NIST SP 800-38B",
    "NIST SP 800-38D; NIST SP 800-38F",
    "NIST SP 800-90A Rev. 1",
    "NIST CSRC Glossary"
  ],
  "url": "https://mlchart.com/terminology/cybersecurity/block-cipher/"
}