bit

Coined by John Tukey in 1946 as an abbreviation of binary digit, probably influenced by connotations of “small portion”. First used in print 1948 by Claude Shannon. Compare byte and nybble, with similar food associations.

status bits on IRC

permission bits in a file system

(information theory, cryptography) Any datum that may take on one of exactly two values.

bit

information theory: datum that may take on one of exactly two values


accumulator

From Latin accumulātor, agent noun of accumulō (“pile up”), accumulate + -or.

(cryptography) A one way membership function.


POW

(cryptography, cryptocurrencies) Alternative letter-case form of PoW (“proof of work”).


rainbow

From Middle English reynbowe, raynbowe, from Old English reġnboga (“rainbow”), from Proto-West Germanic *regnabogō, from Proto-Germanic *regnabugô (“rainbow”), equivalent to rain + bow (“arch”). Cognate with West Frisian reinbôge (“rainbow”), Dutch regenboog (“rainbow”), German Regenbogen (“rainbow”), Danish regnbue (“rainbow”), Swedish regnbåge (“rainbow”), Icelandic regnbogi (“rainbow”).

rainbow attack

(mathematics, cryptography) Of or pertaining to rainbow tables.


CM

en-noun

CM (countable and uncountable, plural CMs)

Sense "commercial" is a borrowing from Japanese CM (CM, “commercial video ad”), from English commercial + message.

(cryptography) Initialism of cryptographic module.


depth

depth (countable and uncountable, plural depths)

From Middle English depthe, from Old English *dīepþ (“depth”), from Proto-Germanic *diupiþō (“depth”), equivalent to deep + -th (abstract nominal suffix). Cognate with Scots deepth (“depth”), Saterland Frisian Djüpte (“depth”), West Frisian djipte (“depth”), Dutch diepte (“depth”), Low German Deepde (“depth”), Danish dybde (“depth”), Icelandic dýpt (“depth”), Gothic 𐌳𐌹𐌿𐍀𐌹𐌸𐌰 (diupiþa, “depth”).

(cryptography) A set of more than one ciphertext enciphered with the same key.


salt

salt (countable and uncountable, plural salts)

Bislama: sol

Tok Pisin: sol

Maori: tote

PIE word
 *séh₂ls
From Middle English salt, from Old English sealt, from Proto-West Germanic *salt, from Proto-Germanic *saltą, from Proto-Indo-European *séh₂ls (“salt”). Doublet of sal, ultimately from Latin sāl (“salt”), which it superseded as the general term for "salt".

take bread and salt Compound words and expressionsabove the saltacid of saltamphid saltAttic saltbaker's saltbath saltbay saltbelow the saltbile saltbronzing saltbutter saltcat-saltcelery saltchicken saltcommon saltcovenant of saltdiazonium saltdishwasher saltdouble saltdry-saltEpsom salt(s)essential saltflake saltFrémy's saltfruit saltgarlic saltGlaser's saltGlauber's saltGreat Salt Lakegreen saltgreen salt of Magnushair-salthair salthartshorn salthei hei saltHimalayan salthorse saltinner saltkoshering saltkosher saltMagnus' green saltMeerwein's saltmicrocosmic saltmineral saltmixed saltMonsel's saltnot worth saltorganic saltpepper-and-saltpinch of saltpink saltplease pass the saltpolychrest saltpound saltpre-salt layerprunella saltput salt on someone's tailroad saltRochelle saltrock saltrub salt in someone's woundsrub salt in the woundsalt acidsalt and peppersalt-and-peppersalt-and-pepper dorissalt beefsalt bottomsalt boxsalt bridgesalt cakesalt cedarsaltcellarsalt-cellarsalt chucksalt claySalt Coatessalt codSalt Creeksalt domesalt doughsalt-effect distillationsalt flatsalt gardensalt glaciersalt glandsalt glazesalt grasssalt-greensalt haySalt Hillsalt horsesalt in the woundsalt junksalt lake → Salt Lake City

Salt Lake Countysalt licksalt linesalt marshsalt-marsh caterpillarsalt marsh haysalt-marsh terrapinsalt meatsalt minesalt of ambersalt of colcotharsalt of hartshornsalt of lemonsalt of Saturnsalt of sodasalt of sorrelsalt of tartarsalt of the earthsalt of tinsalt of Venussalt of vitriolsalt of wormwoodsalt outsalt pansalt pigsalt porksalt rheumsalt-rising breadSalt Riversalt sea

Salt Seasalt sedativesalt shakersalt spoonsaltspoonsalt spray testsalt substitutesalt the minesalt treesalt trucksalt watersalt-watersaltwatersalt water taffysalt wedgesalt worksSchlippe's saltsea saltsedative saltsell salt to a slugsmelling saltspirit of saltspirits of saltsulfur saltsulphur saltsyntactic salttable salttake with a pinch of saltthrow saltTutton's saltwhite saltwith all the salt in the Dead Seaworth one's saltworth one's weight in salt

(cryptography) A sequence of random data added to plain text data (such as passwords or messages) prior to encryption or hashing, in order to make brute force decryption more difficult.

sůl

additional bytes inserted into an encryption


salt

en-verb

salt (third-person singular simple present salts, present participle salting, simple past and past participle salted)

salts (present singular third-person)
salting (participle present)
salted (participle past)
salted (past)

(cryptography) To add filler bytes before encrypting, in order to make brute-force decryption more resource-intensive.


key

From Middle English keye, kaye, keiȝe, from Old English cǣġ (“key, solution, experiment”) (whence also Scots key and kay (“key”)), of uncertain origin. The only sure cognates are Saterland Frisian Koai (“key”), West Frisian kaai (“key”), and North Frisian kay (“key”). Possibly from Proto-Germanic *kēgaz, *kēguz (“stake, post, pole”), from Proto-Indo-European *ǵogʰ-, *ǵegʰ-, *ǵegʰn- (“branch, stake, bush”), which would make it cognate with Middle Low German kāk (“whipping post, pillory”), and perhaps to Middle Dutch keige (“javelin, spear”) and Middle Low German keie, keige (“spear”). For the semantic development, note that medieval keys were simply long poles (ending in a hook) with which a crossbar obstructing a door from the inside could be removed from the outside, by lifting it through a hole in the door. Liberman has noted, however, "The original meaning of *kaig-jo- was presumably '*pin with a twisted end.' Words with the root *kai- followed by a consonant meaning 'crooked, bent; twisted' are common only in the North Germanic languages."

шпи́лка

object used to maintain the orientation between two others

Key in the Encyclopædia Britannica (11th edition, 1911)

(cryptography) A piece of information (e.g., a password or passphrase) used to encode or decode a message or messages.

sleutel

cryptography: piece of information used to encode or decode


malleable

en-adj

malleable (comparative more malleable, superlative most malleable)

more malleable (comparative)
most malleable (superlative)

From Middle French malléable, borrowed from Late Latin malleābilis, derived from Latin malleāre (“to hammer”), from malleus (“hammer”), from Proto-Indo-European *mal-ni- (“crushing”), an extended variant of *melh₂- (“crush, grind”).

(cryptography, of an algorithm) in which an adversary can alter a ciphertext such that it decrypts to a related plaintext


password

passwords (plural)
pass-word (alternative)

From pass + word; the sentry-passing sense predates the cryptographic sense and was its inspiration.

A strong password has a mixture of lowercase and uppercase letters, numbers, and punctuation marks.

(computing, cryptography) A string of characters used to log in to a computer or network, to access a level in a video game, and so on; archetypally a word but nowadays often an alphanumeric string or a phrase.

wagwoord

computing: string of characters known only to a user

passkey

coordinate in its sense contrasted with passwords

keyphrase

used either coordinately or hyponymously; equivalent except for containing spaces


(cryptography) Initialism of Message Digest 5, a cryptographic hash function.


delta

en-verb

delta (third-person singular simple present deltas, present participle deltaing, simple past and past participle deltaed)

deltas (present singular third-person)
deltaing (participle present)
deltaed (participle past)
deltaed (past)

From Ancient Greek δέλτα (délta), borrowed from a Phoenician word for "door", ultimately from Proto-Semitic *dalt-. Doublet of dalet.
* (river): from the triangular shape of the majuscule Greek letter delta Δ
* (USSF): from the delta wing, symbol of the USSF, a triangular wing, shaped like the majuscule Greek letter delta Δ

Turingery worked on deltaed key to produce the deltaed contribution of the chi-wheels. Turing's discovery that delta-ing would reveal information otherwise hidden was essential to the developments that followed.

2007, B. J. Copeland, “Tunny and Colossus: Breaking the Lorenz Schlüsselzusatz traffic”, in Karl de Leeuw, Jan Bergstra, editors, The History of Information Security: A Comprehensive Handbook, Amsterdam: Elsevier, →ISBN, page 458:

(cryptography) To calculate the differences between the characters in an enciphered text and the characters a fixed number of positions previous.


IV

(cryptography) Initialism of initialization vector.


code

en-noun

code (countable and uncountable, plural codes)

desctree

→ Hindi: कूट (kūṭ)
→ Sanskrit: कूट (kūṭa)

→ Japanese: コード (kōdo)

→ Khmer: កូដ (kout)

→ Korean: 코드 (kodeu)

From Middle English code (“system of law”), from Old French code (“system of law”), from Latin cōdex, later form of caudex (“the stock or stem of a tree, a board or tablet of wood smeared over with wax, on which the ancients originally wrote; hence, a book, a writing.”). Doublet of codex.

(cryptography) A cryptographic system using a codebook that converts words or phrases into codewords.


code

en-verb

code (third-person singular simple present codes, present participle coding, simple past and past participle coded)

codes (present singular third-person)
coding (participle present)
coded (participle past)
coded (past)

We should code the messages we send out on Usenet.


IP

en-noun

IP (countable and uncountable, plural IPs)

initial permutation
initial permutation#English

(cryptography) Initialism of initial permutation.


seed

seed (countable and uncountable, plural seeds)

seeds (plural)
sede (alternative obsolete)

]
From Middle English seed, sede, side, from Old English sēd, sǣd (“seed, that which is sown”), from Proto-West Germanic *sād, from Proto-Germanic *sēdą, from Proto-Indo-European *seh₁- (“to sow, throw”).
Cognate with Saterland Frisian Säid (“seed”), West Frisian sied (“seed”), Dutch zaad (“seed”), Low German Saad (“seed”), German Saat (“seed; sowing”), Danish sæd (“seed”), Swedish säd (“seed”), Icelandic sæði (“seed”), Latin satiō (“seeding, time of sowing, season”). More at sow.

alkutilanne

initial state, condition or position of a process

If you use the same seed you will get exactly the same pattern of numbers.

As suggested in [3], space can be saved by using a deterministic pseudo random number generator (PRNG) and storing only the seed of that PRNG.

2009, Daniel J. Bernstein, Johannes Buchmann, Erik Dahmen, editors, Post-Quantum Cryptography, Springer, →ISBN, page 44:

Seeds are Minecraft's way of generating terrain. Each biome you spawn in is determined by the seed. With a custom seed, you can have a desert biome right next to a mesa biome.

2015, Jesse Stay, Thomas Stay, Jacob Cordeiro, Minecraft For Dummies, John Wiley & Sons, →ISBN, page 242:

pseudorandom number generator
pseudorandom number generator

(countable) The initial state, condition or position of a changing, growing or developing process; the ultimate precursor in a defined chain of precursors.

(cryptography) The initialization state of a pseudorandom number generator or similar system. (seed number)


pepper

en-noun

pepper (countable and uncountable, plural peppers)

peppers (plural)
piper (alternative archaic)

Tok Pisin: pepa

→ Hawaiian: pepa

→ Marshallese: pepa

From Middle English peper, piper, from Old English piper, from Proto-West Germanic *pipar, from Latin piper, from an Indo-Aryan source; compare Sanskrit पिप्पलि (pippali, “long pepper”). The name was given to the capsicum fruit because of its unusual spicy taste, not unlike the Old World spice. Cognate with Scots pepar, Saterland Frisian Pieper, West Frisian piper, Dutch peper, German Low German Peper, German Pfeffer, Danish peber, Swedish peppar, Icelandic pipar. Doublet of falafel and peepul.

cog

(cryptography) A randomly-generated value that is added to another value (such as a password) prior to hashing. Unlike a salt, a new one is generated for each value and it is held separately from the value.


pepper

en-verb

pepper (third-person singular simple present peppers, present participle peppering, simple past and past participle peppered)

peppers (present singular third-person)
peppering (participle present)
peppered (participle past)
peppered (past)
piper (alternative archaic)

(cryptography) To use a pepper (type of value used prior to hashing).


asymmetric

en-adj

asymmetric (comparative more asymmetric, superlative most asymmetric)

more asymmetric (comparative)
most asymmetric (superlative)

From a- + symmetric, as Ancient Greek ἀσυμμετρία (asummetría, “disproportion, deformity”).

der

(cryptography) Not involving a mutual exchange of keys between the sender and receiver.


symmetric

en-adj

symmetric (comparative more symmetric, superlative most symmetric)

more symmetric (comparative)
most symmetric (superlative)

From symmetry + -ic, from Latin symmetria, from Ancient Greek συμμετρία (summetría).

(cryptography) Using the same key (or keys that are trivially related) for both encryption and decryption.


fingerprint

fingerprints (plural)
finger-print (alternative)

/ˈfɪŋɡɚˌpɹɪnt/

asymmetric cryptography
asymmetric cryptography

(cryptography) A unique identification for a public key in asymmetric cryptography.

بَصْمَة

unique identification for public key in asymmetric cryptosystem


aristocrat

/ˈæɹɪstəˌkɹæt/

/əˈɹɪstəˌkɹæt/

From French aristocrate (“aristocrat”), attested once in the 16th century but recoined in the Revolutionary era, from aristocratie (“aristocracy”), from Medieval Latin aristocratia, from Ancient Greek ἀριστοκρατία (aristokratía), from ἄριστος (áristos, “best”) (compare Old English ar) + κράτος (krátos, “rule”). By surface analysis, aristo- + -crat.

der

ἀριστοκρατία

Coordinate term: patristocrat

(cryptography) A cipher in which the original punctuation and spacing are retained.


block

→ Dutch: block

→ German: Block

→ Irish: bloc

→ Manx: block

→ Maori: poraka

→ Norwegian: blokk

→ Polish: blok

desctree

→ Russian: блок (blok)
→ Armenian: բլոկ (blok)
→ Yakut: блок (blok)

→ Spanish: block

→ Vietnamese: lốc

From Middle English blok (“log, stump, solid piece”), from Old French bloc (“log, block”), from Middle Dutch blok (“treetrunk”), from Old Dutch *blok (“log”), from Proto-West Germanic *blokk, from Proto-Germanic *blukką (“beam, log”), from Proto-Indo-European *bʰelǵ- (“thick plank, beam, pile, prop”). Cognate with Old Frisian blok, Old Saxon blok, Old High German bloh, bloc (“block”), Old English bolca (“gangway of a ship, plank”), Old Norse bǫlkr (“divider, partition”). More at balk. See also bloc, bulk.

طَابُوقَة

substantial often approximately cuboid piece

թաղամաս

group of buildings demarcated by streets

A logical extent or region; a grouping or apportionment of like things treated together as a unit.

(cryptography) A fixed-length group of bits making up part of a message.

lohko

cryptography: fixed-length group of bits making up part of a message


pad

1554, "bundle of straw to lie on", probably from Low German or West Flemish pad (“sole of the foot”), perhaps ultimately from Proto-Indo-European *pent- (“to pass”), which would make it related to both path and find.

unk

probably

(cryptography) A random key (originally written on a disposable pad) of the same length as the plaintext.


Alice

From Middle English Alice, from Old French Alys, Alice, from Old High German Adalheidis, proposed to derive from Proto-Germanic *aþalaz (“noble”) + *haiduz (“character”). Doublet of Adelaide.

af

Alice sends the message, "I am Alice," to Bob. Bob chooses a nonce, N and sends it to Alice. Alice encrypts the nonce using Alice and Bob's symmetric secret key, K#95;#123;A-B#125;, and sends the encrypted nonce, K#95;#123;A-B#125;(N) back to Bob.

1978, V.S. Bagad, I.A. Dhotre, Computer Networks, Technical Publications, →ISBN:

Alice opens her lantern, Bob opens his the instant he sees Alice's, and Alice notes the time T that passes between the moment she opens hers and the moment she sees the light returning to her from Bob's.

2009, N. David Mermin, It's About Time: Understanding Einstein's Relativity, Princeton University Press, →ISBN, page 19:

(cryptography, physics) The person or system that sends a message to another person or system conventionally known as Bob.


cipher

ciphers (plural)
cypher (alternative uncommon)

14th century. From Middle English cifre, from Old French cyfre, cyffre (French chiffre), ultimately from Arabic صِفْر (ṣifr, “zero, empty”), from صَفَرَ (ṣafara, “to be empty”). Doublet of chiffre and zero. Sense 8 (a fault in an organ valve) may be a different word.

a public-key cipher

(cryptography) A cryptographic system using an algorithm that converts letters or sequences of bits into ciphertext.


nonce

Inherited from Middle English nonse, nones, a rebracketing of Middle English to þen anes, for þen anes (to/for the once (i.e., the one occasion or instance)), from the dative singular neuter of þe. The cryptography sense is commonly said to be a contraction of number used once, although this is probably incorrect.

gl

The protocol opens with A communicating in clear to AS his own claimed identity and the identity of the desired correspondent, B, together with A's nonce identifier for this transaction, I_(A1). ("Nonce" means "used only once.")

1978 December 2, Roger M. Needham, “Using Encryption for Authentication in Large Networks of Computers”, in Communications of the ACM, volume 21, number 12:

The information gained by the eavesdropper would permit a replay attack, but only with a request for the same document, and even that may be limited by the server's choice of nonce.

1999, Network Working Group, RFC 2617 – HTTP Authentication: Basic and Digest Access Authentication, The Internet Society, page 22

Both CCM and GCM require a unique nonce (N used once) value to maintain their privacy and authenticity goals.

2006, Tom St Denis, Cryptography for Developers, page 340:

The main idea with the challenge-response type of authentication protocol is that the challenge sent by the server is used only once (referred to as a cryptographic nonce, which means “number used once”).

2012, Steven Anson, Mastering Windows Network Forensics and Investigation:

(cryptography) A value constructed so as to be unique to a particular message in a stream, in order to prevent replay attacks.


digest

From Latin dīgesta, neuter plural of dīgestus, past participle of dīgerō (“separate”).

(cryptography) The result of applying a hash function to a message.

resumo

cryptography: the result of applying a hash function to a message


knapsack

From Low German knapzak or Dutch knapzak (older form cnapsack), from Middle Dutch cnappen (“to bite with teeth”), ultimately from knappen (“to eat, crack”), of imitative origin, + sack. German Knappsack is from Dutch.

onomatopoeic

imitative

(cryptography) A set of values from which a subset is chosen.


tweak

From Middle English twikken, from Old English twiccian (“to pluck”), from Proto-West Germanic *twekkōn (“to fasten; clamp; pinch”). Related to twitch. The drug-related sense may be a blend of twitch and freak.

inh

(cryptography) An additional input to a block cipher, used in conjunction with the key to select the permutation computed by the cipher.


key exchange

en-noun

key exchange (countable and uncountable, plural key exchanges)

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-key exchange.wav

(cryptography) An exchange of peers' keys at the initialization phase of connection.


RSA

(cryptography) Initialism of Rivest-Shamir-Adleman (“an encryption algorithm”).


MDC

modification detection code
w:Modification Detection Code

(cryptography) Initialism of modification detection code.


signature

/ˈsɪɡnət͡ʃə(ɹ)/

/ˈsɪɡnɪt͡ʃə(ɹ)/

/ˈsɪɡnət͡ʃɚ/

/ˈsɪɡnɪt͡ʃɚ/

/ˈsɪɡnɪt͡ʃə(ɹ)/

Borrowed from Middle French signature, or from Medieval Latin signātūra, future active periphrastic of verb signāre (“to sign”) from signum (“sign”), + -tūra, feminine of -tūrus, future active periphrastic suffix. Displaced native Old English handseten (literally “hand setting”).

ncog

(cryptography) Data attached to a message that guarantees that the message originated from its claimed source.

簽名 /签名

cryptography: data attached to a message that guarantees that the message originated from its claimed source


keyring

keyrings (plural)
key ring (alternative)

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-keyring.wav

(cryptography) A set of data holding linked encryption keys.

密鑰環 /密钥环

cryptography: set of data holding linked keys


keyserver

keyservers (plural)
key server (alternative)

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-keyserver.wav

public key cryptography
public key cryptography

(cryptography) In public key cryptography, the server that stores and distributes the public key files.


encryption

en-noun

encryption (usually uncountable, plural encryptions)

/ɪnˈkɹɪpʃən/

/ɛnˈkɹɪpʃən/

/ɪŋˈkɹɪpʃən/

Fully homomorphic encryption (FHE) is a new encryption technique that enables computing on data blindly, without decrypting it.

2023 May 26, Rand Hindi, “How Homomorphic Encryption Can Make Blockchain Private”, in Forbes, New York, N.Y.: Forbes Media, →ISSN, →OCLC, archived from the original on 2023-06-12:

(cryptography) The process of obscuring information to make it unreadable without special knowledge, key files, or passwords.

As ZT() can only test whether a single ciphertext is an encryption of zero, it cannot work when there are more than one ciphertext to test.

2005, Kun Peng, Colin Boyd, Ed Dawson, Byoungcheon Lee, An Efficient And Verifiable Solution To The Millionaire Problem:

(cryptography) A ciphertext, a cryptogram, an encrypted value. Usually used with the preposition "of" followed by the value that is hidden in it.


PGP

Pretty Good Privacy
Pretty Good Privacy#English

(encryption, software) Initialism of Pretty Good Privacy, a program using public key encryption popularly used with email.


public key

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-public key.wav

Coordinate term: private key

(cryptography) One of the two keys used in asymmetric cryptography, which is published to others.

clau pública

the public one of the two keys used in asymmetric cryptography


whiten

en-verb

whiten (third-person singular simple present whitens, present participle whitening, simple past and past participle whitened)

whitens (present singular third-person)
whitening (participle present)
whitened (participle past)
whitened (past)

From Middle English whitenen, whitnen, from Old Norse hvítna (“to whiten”), from Proto-Germanic *hwītnōną (“to whiten, become white”), from Proto-Indo-European *kwind-, *kwint- (“bright”), equivalent to white + -en. Cognate with Icelandic hvítna (“to whiten”), Swedish vitna, hvitna (“to whiten”), Danish hvidne (“to whiten”). Compare Old English hwītian (“to whiten, become white, be white, make white”).

cog

(cryptography) To increase the security of an iterated block cipher by steps that combine the data with portions of the key.


crib

en-noun

crib (countable and uncountable, plural cribs)

From Middle English crib, cribbe, from Old English crib, cryb, cribb, crybb (“couch, bed; manger, stall”), from Proto-West Germanic *kribbjā, from Proto-Germanic *kribjǭ (“crib, wickerwork”), from Proto-Indo-European *grebʰ-, *gerbʰ- (“bunch, bundle, tuft, clump”), from *ger- (“to turn, twist”).
Cognate with Saterland Frisian Kräbbe, Krääb, Krääf (“crib”), West Frisian krêbe (“crib”), Dutch krib (“crib, manger”), German Krippe (“rack, crib”), Danish krybbe (“crib”), Icelandic krubba (“crib”). Doublet of crèche. The sense of ‘stealing, taking notes, plagiarize’ seems to have developed out of the verb.
The criminal sense may derive from the 'basket' sense, circa the mid 18th century, in that a poacher could conceal poachings in such a basket (see the 1772 Samuel Foote quotation). The cheating sense probably derives from the criminal sense.

inh

(cryptography) A known piece of information corresponding to a section of encrypted text, that is then used to work out the remaining sections.


crib

en-verb

crib (third-person singular simple present cribs, present participle cribbing, simple past and past participle cribbed)

cribs (present singular third-person)
cribbing (participle present)
cribbed (participle past)
cribbed (past)

(cryptography) To use a known piece of information corresponding to a section of encrypted text, to work out the remaining sections.


pigpen

[ˈpʰɪɡˌpʰɛn]


Bob

Probably from a medieval hypocorism of Rob.

The key that Alice and Bob are to share cannot be transmitted in the clear. Either it must be enciphered when sent, or Alice and Bob must derive it without an exhange of data from which the key can be derived.

2003, Matt Bishop, Computer Security: Art and Science, Addison-Wesley Professional, →ISBN, page 247:

(cryptography, physics) The person or system receiving a message or signal from a source conventionally known as Alice.


Eve

(cryptography) A conventional name for an agent attempting to intercept a message sent by Alice that is intended for Bob.


Mallet

Cryptographic scenarios use archetypal characters with standard names chosen to remember their role: Mallet was derived from "malicious" and "man-in-the-middle attack", as well as the tool mallet.

Even if Alice and Bob's public keys are stored on a datavase, this attack will work. Mallet can intercept Alice's database inquiry, and substitute his own public key for Alice's. He can do the same to Bob.

1994, Bruce Schneier, Applied Cryptography, →ISBN, page 44:

(cryptography) The malicious party in examples of threat scenarios. See Alice and Bob.


Victor

From a Late Latin personal name Victor, borne by several saints, from victor (“conqueror”). Doublet of victor.

Coordinate term: Peggy

(cryptography) Placeholder name for the party that verifies a proof.


MAC

en-noun

MAC (countable and uncountable, plural MACs)

message authentication code
w:message authentication code

(cryptography) Initialism of message authentication code.


padding

padding (countable and uncountable, plural paddings)

(military, cryptography) Extraneous text added to a message for the purpose of concealing its beginning, ending, or length.


CSR

CSR (countable and uncountable, plural CSRs)

(cryptography) Initialism of certificate signature request.


SAN

SAN (countable and uncountable, plural SANs)

Subject Alternative Name
w:Subject Alternative Name

(cryptography, computer security) Acronym of Subject Alternative Name.


OTP

(cryptography) Initialism of one-time pad.


PKC

public-key cryptography
public-key cryptography#English

(cryptography) Initialism of public-key cryptography.


autoclave

Borrowed from French autoclave, formed with prefix auto- + Latin clavis (“key”).


trapdoor

trapdoors (plural)
trap door (alternative)
trap-door (alternative)

(mathematics, cryptography) The special information that permits the inverse of a trapdoor function to be easily computed.


trapdoor

en-verb

trapdoor (third-person singular simple present trapdoors, present participle trapdooring, simple past and past participle trapdoored)

trapdoors (present singular third-person)
trapdooring (participle present)
trapdoored (participle past)
trapdoored (past)
trap door (alternative)
trap-door (alternative)

(cryptography, transitive) To subvert (a cryptographic scheme) by means of a secret parameter that makes the trapdoor function easy to compute.


Peggy

Coordinate term: Victor

(cryptography) Placeholder name for the party that supplies a proof.


decode

If and when the remaining Allied intercepts and decodes are opened up, we may expect to learn a great deal more about the later stages of the Holocaust.

2004, David Cesarani, Holocaust: Responses to the Persecution and Mass Murder of the Jews, page 148:

The British picked up a decode in November 1942 indicating that guards at Auschwitz would need six hundred gas masks.

2005, Richard Breitman, U.S. Intelligence And The Nazis, page 31:

Decodes stating that Hollandia airfields were becoming overcrowded with IJA aircraft waiting to stage forward to Wewak led to pre-emptive strikes by Allied air forces and the destruction of more than 300 Japanese aircraft on the ground.

2006, Ian Pfennigwerth, A Man of Intelligence, page 223:

He was sure that references to AK in the intercepts stood for Midway, but none of the decodes made the identification certain.

2011, Hervie Haufler, Codebreakers' Victory, page 192:


plain text

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-plaintext.wav

Using the sophisticated code was useless since the spy merely stole the plain text from the waste basket.

(cryptography) Text or any data that is to be encrypted (as opposed to ciphertext).


plain text

(cryptography, computing) Alternative spelling of plaintext.


DES

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-DES.wav

(cryptography) Initialism of Data Encryption Standard.


plaintext

There are weak keys in the sense that their use by foisting chosen plaintexts can be proved, which could be interesting for chip cards with a ‘burnt-in key’.

2007, Reinhard Wobst, “Life After DES: New Methods, New Attacks”, in Angelika Shafir, transl., Cryptology Unlocked, John Wiley & Sons, Ltd, →ISBN, section 3 (IDEA: A Special-Class Algoritmh), subsection 5 (Cryptanalyzing IDEA), page 239:

(cryptography, computing) Alternative spelling of plain text.


SMP

en-noun

SMP (countable and uncountable, plural SMPs)

socialist millionaire problem
w:Socialist millionaires

(cryptography) Initialism of socialist millionaire problem.


computationally secure

en-adj

computationally secure (comparative more computationally secure, superlative most computationally secure)

more computationally secure (comparative)
most computationally secure (superlative)

(cryptography) Not decodable with all available computer power.


SRES

The network sends a challenge to the mobile at each connection, and the mobile must send an SRES back to the network before it will allow access.

(telecommunications, cryptography) Acronym of signed response (to an authentication challenge on GSM mobile networks).


spn

substitution-permutation network
w:substitution-permutation network

(cryptography) Initialism of substitution-permutation network.


malleability

en-noun

malleability (countable and uncountable, plural malleabilities)

(cryptography) a property of a cryptographic algorithms in which an adversary can alter a ciphertext such that it decrypts to a related plaintext


keyword

keywords (plural)
key word (alternative)
key-word (alternative)

Coordinate term: keyphrase

(cryptography) Any word used as the key to a code.


substitution cipher

substitution cipher (plural substitution ciphers)

(cryptography) A method of encryption by which units of plaintext are substituted with ciphertext according to a regular system; the "units" may be single letters (the most common), pairs of letters, triplets of letters, mixtures of the above, and so forth. The receiver deciphers the text by performing an inverse substitution.


foursquare

en-adj

foursquare (comparative more foursquare, superlative most foursquare)

more foursquare (comparative)
most foursquare (superlative)

From Middle English foure square; equivalent to four + square.

(cryptography) Pertaining to a four-square cipher.


foursquare

en-noun

foursquare (countable and uncountable, plural foursquares)

(countable, cryptography) A four-square cipher.


LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-3DES.wav

(cryptography, informal) Abbreviation of Triple DES, a cipher formed from the Data Encryption Standard (DES) cipher by using it three times.


fractionation

fractionation (countable and uncountable, plural fractionations)

By surface analysis, fraction + -ation, or, by surface analysis, fractionate + -ion.

(cryptography) A preliminary stage of encryption that divides each plaintext symbol into several ciphertext symbols.


birthday attack

birthday attack (plural birthday attacks)

(cryptography) A covert method of decryption exploiting the so-called birthday paradox.


rainbow table

Coined by cryptanalyst Philippe Oechslin in 2003.

coined

(mathematics, cryptography) A table of surjective functions used to decrypt a text that was coded using a hash table.


unsalted

(cryptography) Without a cryptographic salt.


keychain

keychains (plural)
key chain (alternative)

(cryptography) A digital repository for the storage of cryptographic keys.


Mallory

From an Anglo-Norman nickname for an unfortunate person, from Old French maleure, malheure (“unhappy, unlucky”) (whence French malheur), from mal (“bad”) + eur (“fortune”).

(cryptography, computer security) The malicious party in examples of threat scenarios. See Alice and Bob.


zero-knowledge proof

en-noun

zero-knowledge proof (plural zero-knowledge proofs)

Implementation of a zero-knowledge proof significantly improves the privacy and security of many systems. However, it introduces additional costs in processing power and hard drive space.

2020, Lorne Lantz, Daniel Cawrey, Mastering Blockchain, O'Reilly Media, →ISBN, page 185:

This issue of privacy in blockchain isn't new, and many ideas have been proposed, such as keeping the data off-chain and using zero-knowledge proofs (ZKPs) to prove we did the right computation (e.g., Aleo and Aztec) or using mixnets to anonymize transactions (e.g., Tornado Cash).

(cryptography) An interactive method for one party to prove to another that a (usually mathematical) statement is true, without revealing anything other than the veracity of the statement.

preuve à divulgation nulle de connaissance


fractionate

en-verb

fractionate (third-person singular simple present fractionates, present participle fractionating, simple past and past participle fractionated)

fractionates (present singular third-person)
fractionating (participle present)
fractionated (participle past)
fractionated (past)

From fraction + -ate (verb-forming suffix).

(cryptography) To divide each plaintext symbol into several ciphertext symbols as a preliminary stage of encryption.


CSPRNG

pseudorandom number generator
pseudorandom number generator#English

(cryptography) Initialism of cryptographically secure pseudorandom number generator.


codebook

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In the 19th century codebooks were used not so much for secrecy as for compression, to bring down the prohibitive cost of telegraph communication. […] But when Dr. Bellovin hunted though the card catalog, his interest was piqued by an 1882 codebook whose title included the word “secrecy.”

2011 July 25, John Markoff, “Codebook Shows an Encryption Form Dates Back to Telegraphs”, in The New York Times:

(cryptography) A book, table, database, or other object that stores the mapping between plaintext words or phrases and their equivalents in a code.

salakirjoitusavain

cryptography: mapping between plaintext and code


ECC

en-noun

ECC (countable and uncountable, plural ECCs)

(cryptography) Initialism of elliptic curve cryptography.


cleartext

cleartext (countable and uncountable, plural cleartexts)

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-cleartext.wav

(cryptography) The unencrypted form of an encrypted text; plain text


unblind

en-verb

unblind (third-person singular simple present unblinds, present participle unblinding, simple past and past participle unblinded)

unblinds (present singular third-person)
unblinding (participle present)
unblinded (participle past)
unblinded (past)

(cryptography, transitive) To convert (a blind signature) back to the unblinded state (as opposed to the blinded state).


MITM

Man-in-the-middle attack
Meet-in-the-middle attack

(cryptography) Initialism of meet-in-the-middle attack: Cryptographic attack that attempts to find a value in each of the ranges and domains of the composition of two functions such that the forward mapping of one through the first function is the same as the inverse image of the other through the second function.


codeword

Bob cannot get any information out of the codeword since he doesn't know what transmission bases Alice used.

(cryptography) A string representing an encoded piece of text.


FS

(cryptography) Initialism of forward secrecy.


(cryptography) Having had its MD5 checksum computed.


tweakable

en-adj

tweakable (comparative more tweakable, superlative most tweakable)

more tweakable (comparative)
most tweakable (superlative)

(cryptography, not comparable) Of a block cipher: accepting a second input (the "tweak"), used in conjunction with the key to select the permutation computed by the cipher.


keyspace

en-noun

keyspace (countable and uncountable, plural keyspaces)

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-keyspace.wav

(cryptography) The notional space that contains all possible cryptographic keys.


unkeyed

an unkeyed hash function

(computing, cryptography) Without a key.


keyphrase

(cryptography) A phrase used in encryption as a key, like a single keyword (password).


monoalphabetic

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-monoalphabetic.wav

(cryptography) Of a substitution cipher, using the same fixed mappings from plaintext to cipher letters across the entire text.


cilly

Uncertain; possibly a pun on silly and the letters CIL used as a cryptographic key.

Another type of cilly was the repeated use of the same message key, perhaps the initials of the operator's girlfriend […]

Answer c is a reference to a cilly, which was a three-character message key used in the German Enigma machine.

2002, Ronald L Krutz, Russell Dean Vines, The CISSP Prep Guide: Gold Edition:

Taunt describes the work involved in breaking Enigma messages, cribs, cillies, the Herivel tip, help from Bombes and more.

2005, Brian J Winkel, Cipher A Deavours, David Kahn, Louis Kruh, The German Enigma cipher machine:

By 1944, cillies had already become rare; hence, Bletchley Park had already found other breaks into the Enigma nets.

2006, Rebecca Ann Ratcliff, Delusions of intelligence: Enigma, Ultra and the end of secure ciphers:

Cillies resulted from a combination of two different mistakes in a multi-part message by some Enigma operators.

2007, Friedrich Ludwig Bauer, Decrypted secrets: methods and maxims of cryptology:

(cryptography, historical) Any predictable facet of the Enigma Machine cipher due to operator error or laziness, whose existence helped the Allies to break the code.


integrity

integrity (countable and uncountable, plural integrities)

/ɪnˈtɛɡɹəti/

/ɪnˈtɛɡɹɪti/

Borrowed from Middle French intégrité, from Latin integritās (“soundness, integrity”), from integer. Doublet of entirety.

der

(cryptography) With regards to data encryption, ensuring that information is not altered by unauthorized persons in a way that is not detectable by authorized users.


atomic authorization

en-noun

atomic authorization (countable and uncountable, plural atomic authorizations)

(cryptography) (A digitally signed document containing) published rights with cryptographically verifiable integrity, secured independently of the applications that utilize them and entities to which they apply.


idiomorph

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-idiomorph.wav


multicollision

a multicollision attack

(cryptography) Involving multiple hash collisions.


keystream

(cryptography) A stream of random or pseudorandom characters that are combined with the plaintext to produce a ciphertext.


black chamber

(historical, cryptography, informal) A government or royal court's cryptanalyst department.


QKD

(cryptography) Initialism of quantum key distribution.


stego

Clipping of various terms relating to steganography.

A stego text might become meaningless if words of the cover text are freely replaced to synonyms without considering the context.

2013, Kazuhiro Kondo, Multimedia Information Hiding Technologies and Methodologies for Controlling Data, Hershey, P.A.: Information Science Reference, →ISBN, page 357, column 1:

(cryptography) Steganographic; relating to or hidden using steganography.


stego

stego (countable and uncountable, plural stegos)

One might use traditional steganalysis to find stegos and then identify the guilty actors.

2020, Hanzhou Wu, “Unsupervised steganographer identification via clustering and outlier detection”, in Mahmoud Hassaballah, editor, Digital Media Steganography, London: Academic Press, →ISBN, page 296:

(countable, cryptography) A secret message hidden using steganography.


oblivious transfer

oblivious transfer (plural oblivious transfers)

(cryptography) A transfer in which a sender sends some information to a receiver but does not know what is received.


VMS

(cryptography) Initialism of Voynich manuscript.


dictionary attack

dictionary attack (plural dictionary attacks)

/ˌdɪkʃənəɹi əˈtæk/

/ˌdɪkʃəˌnɛɹi əˈtæk/

Experts warn against using ordinary words as passwords as they are vulnerable to dictionary attacks.

(computing, cryptography) An attempt to illegally access a computer network, website, etc., that uses a list of words (from a dictionary) to try to guess decryption keys or passwords.

هجوم المعجم

attempt to illegally access a computer network, website, etc., that uses a list of words to try and guess decryption keys or passwords


cryptoprocessor

(cryptography) A dedicated computer on a chip or microprocessor that carries out cryptographic operations.


cryptoprocessing

(cryptography) Cryptographic operations carried out by a computer or cryptoprocessor.


one-time pad

One-time pads have been proven to be impossible to crack if used correctly.

(cryptography) A form of encryption where each bit or character from the plaintext is encrypted by a modular addition with a bit or character from a secret random key (or pad) of the same length as the plaintext.


avalanche effect

avalanche effect (plural avalanche effects)

(cryptography) A property of some cipher systems in which a small change in the input results in a very large change in the output.


zeroization

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-zeroization.wav

(cryptography) The erasure of sensitive parameters from a cryptographic module to prevent their disclosure if the equipment is captured.


Playfair

Playfair (countable and uncountable, plural Playfairs)

* (craters): The craters are Named after Scottish mathematician, scientist and C of S minister John Playfair
* (cipher): The cipher is Named after British Lord, baron, politician and scientist Lyon Playfair, who popularized the cipher.

named-after

(cryptography) Ellipsis of Playfair cipher.

Here's a cipher message. Probably Playfair.

(cryptography) an encryption using the Playfair cipher


keyholder

keyholders (plural)
key holder (alternative)

LL-Q1860 (eng)-Flame, not lame-keyholder.wav

A key duplicating machine comprising […] a keyholder attached to said shaft, said keyholder providing for holding a key blank and an existing key having notches thereon; […]

1978, Official Gazette of the United States Patent and Trademark Office, page 32:

(cryptography) The individual or organization with access to a cryptographic key.


trapdoor function

en-noun

trapdoor function (plural trapdoor functions)

From the idea that it is easy to fall through a trapdoor but difficult to climb back out.

(mathematics, cryptography) A function that is easy to compute in one direction but difficult to compute in the opposite direction (finding its inverse) without special information.


semiweak

There are 2⁵⁶ (7.21 × 10¹⁶, about 72 quadrillion) possible keys for DES, of which four are weak and twelve are semiweak.

(cryptography, Data Encryption Standard) Producing only two different subkeys.


stream cipher

(cryptography) a symmetric-key cipher in which plaintext digits are combined with a pseudorandom cipher digit stream


PFS

perfect forward secrecy
w:perfect forward secrecy

(cryptography) Initialism of perfect forward secrecy.


presignature

(cryptography) An intermediate value used in forming a signature, unrelated to the contents of the message being signed.


blindable

Finally, we use the term additive joint encryption scheme to denote a secure, blindable, xor-homomorphic, witnessed probabilistic public-key joint encryption scheme.

1994, Douglas R. Stinson, Advances in cryptology: CRYPTO '93, 13th Annual International Cryptology Conference, Santa Barbara, California, USA, August 22-26, 1993: proceedings:

Blindable encryption also provides a useful way to make a given ciphertext unrecognizable.

2004, Ari Juels, Financial Cryptography: 8th International Conference: volume 8, page 188:

(cryptography) Such that, given an encrypted bit (binary digit), anybody can create a random ciphertext decrypting to the same bit.


Russian copulation

(cryptography) A method of rearranging plaintext before encryption by breaking it into two parts and inverting their order, so as to conceal obvious headers, salutations, signatures, etc.


keypair

keypairs (plural)
key pair (alternative)

public-key cryptography
public-key cryptography

(cryptography) A public key and its associated private key (in public-key cryptography).


preshared

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-preshared.wav

(cryptography, of a key or secret) Shared between the communicating parties by some secure channel before it needs to be used.


Turingery

From Turing + -ery, after its inventor Alan Turing.

(cryptography) A manual cryptanalysis technique used in breaking the Lorenz cipher during World War II, based on deducing the wheel settings of the machine that did the encryption.


autokey

(cryptography) Being a cipher that incorporates the plaintext into the key.


MMB

(cryptography) Initialism of modular multiplication-based block cipher.


Merkle tree

Named after American computer scientist Ralph Merkle (1952–), who patented it in 1979.

named-after

2001, Josep Domingo-Ferrer, Mobile Agent Route Protection through Hash-Based Mechanisms, C. Pandu Rangan, Cunsheng Ding (editors), Progress in Cryptology - INDOCRYPT 2001: 2nd International Conference, Proceedings, Volume 2, Springer, LNCS 2247, page 17,
The second solution uses Merkle trees and minimizes the cost of route protection by the agent owner, so that a single digital signature suffices to protect the whole route; for hosts along the route, the verification cost is similar to the cost of previous schemes in the literature, namely one digital signature verification per route step.

2004, Michael Szydlo, Merkle Tree Traversal in Log Space and Time, Christian Cachin, Jan Camenisch (editors), Advances in Cryptology - EUROCRYPT 2004: International Conference, Proceedings, Springer, LNCS 3027, page 541,
Merkle trees have found many uses in theoretical cryptographic constructions, having been specifically designed so that a leaf value can be verified with respect to a publicly known root value and the authentication data of the leaf.

In order to support dynamic data operations, the Merkle Tree is made dynamic by making use of relative index.

2015, Puonam M. Pardeshi, Bharat Tidke, “Improvement of Data Integrity and Data Dynamics for Data Storage Security in Cloud Computing”, in J. K. Mandal, Suresh Chandra Satapathy, Manas Kumar Sanyal, Partha Pratim Sarkar, Anirban Mukhopadhyay, editors, Information Systems Design and Intelligent Applications, Proceedings of 2nd International Conference, Volume 1, Springer, page 279:

(computer science, cryptography) A binary hash tree.


Polybius square

en-noun

Polybius square (plural Polybius squares)

From Polybius + square (“grid”). It was invented by the Ancient Greek historian and scholar Polybius.

(cryptography) A grid used for fractionating plaintext characters so that they can be represented by a smaller set of symbols.


rubber-hose cryptanalysis

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-rubber-hose cryptanalysis.wav

Referring to the use of a rubber hose as a weapon to beat somebody with.

We have shown that GNUnet is vulnerable to rubber-hose cryptanalysis, but we additionally have presented an efficient content filter for GNUnet. If content filtering is legally enforced, censoring GNUnet is possible at a very large scale.

2003, Dennis Kügler, “An Analysis of GNUnet”, in Privacy Enhancing Technologies: Third International Workshop, edited by Roger Dingledine, Springer Science & Business Media, →ISBN, page 175:

Catherine scooted out of the way, giving Terry access to the keyboard. With a labored sigh, Terry began searching the encrypted text. “I could try a ciphertext-only attack,” he mumbled to no one in particular. “Then again,” he glared at the attacker and continued, “I could always try rubber-hose cryptanalysis.” He thought for a moment. “I don't need a total break; I'm only interested in information deduction. Let me check the swap file.”

2005, Ryan Russell, Peter A Riley, Jay Beale, Chris Hurley, Tom Parker, Brian Hatch, Stealing the Network: How to Own an Identity: How to Own an Identity, Syngress, →ISBN, page 279:

Other types of cryptanalytic attacks include chosen cipher text, chosen key, rubber hose cryptanalysis, and purchase key. Algorithms differ by degrees of security; this depends on how hard they are to break.

2010, Hazarathaiah Malepati, Digital Media Processing: DSP Algorithms Using C, Newnes, →ISBN, page 18:

(cryptography, euphemistic) The extraction of cryptographic secrets by coercion or torture.


Cardan grille

Proposed in 1550 by Girolamo Cardano (1501-1576), known in French as Jérôme Cardan.

(cryptography) A sheet of card or thin metal, etc., used in composing secret messages. The words of the message are written through a number of holes cut arbitrarily in the sheet, and the remaining paper is then filled with irrelevant words to disguise it.


split key

Moreover, even those systems (such as split key systems) that can decrease these risks, do so with a marked increase in cost.

1997, Cryptography and Privacy Sourcebook, →ISBN, page 15:

A toolkit for split key cryptography in and of itself is (almost) a byproduct of developing ultra-high assurance applications such as root certifying authorities.

2007, Matt Blaze, Financial Cryptography, →ISBN, page 233:

Camenisch et al. [CCGS10] define, among other things, split key exchange and give a construction based on the decisional Diffie-Hellman assumption.

2014, Michel Abdalla, Roberto De Prisco, Security and Cryptography for Networks, →ISBN, page 45:

(cryptography) A cryptographic key that is divided into two or more values that individually cannot be used to deduce the entire key.


web of trust

(cryptography) A decentralized cryptographic mechanism for establishing the authenticity of the binding between a public key and its owner.


monoliteral

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-monoliteral.wav

(cryptography) That uses a single letter as a cipher


cryptoviral extortion

(cryptography, computer security, Internet) A data kidnapping attack studied in the field of cryptovirology, in which malware encrypts user data and asks for payment in exchange for the decryption key.


cryptoviral

(cryptography, computer security) related to a cryptovirus


secret sharing

(cryptography) Any method for distributing a secret amongst a group of participants, each of whom is allocated a share; the secret can be reconstructed only when a sufficient number of shares (possibly of different types) are combined.


Feistel cipher

Named after the German-born physicist and cryptographer Horst Feistel.

(cryptography) A symmetric structure used in the construction of block ciphers. It is an iterated cipher with an internal function called a round function.


GCM

Galois/Counter Mode
w:Galois/Counter Mode

(cryptography) Initialism of Galois/Counter Mode.


cryptovirology

(cryptography, computer security) The use of cryptography to design powerful malicious software such as ransomware and asymmetric backdoors.


Diffie-Hellman

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-Diffie-Hellman.wav

Named after Whitfield Diffie and Martin Hellman.

(cryptography) A particular mechanism for key exchange in cryptographic communications.


Kerckhoffs's principle

(cryptography) The idea that a cryptosystem should be designed to be secure even if everything about the system, except the secret key, is public knowledge.

Auguste Kerckhoffs
Kerckhoffs's principle


cryptovariable

(cryptography) The key used for encryption and decryption.


block cipher

(cryptography) Any deterministic cipher that operates on fixed-size groups of bits (binary digits), called blocks, with an unvarying transformation specified by a symmetric key.


cryptofunction

(cryptography) A mathematical function used to carry out cryptography.


pubkey

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-pubkey.wav


key stretching

(cryptography) Techniques used to make a key more secure against brute force attacks by increasing the resources needed to test each possible key.


S-box

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-S-box.wav

In block ciphers, S-boxes are typically used to obscure the relationship between the key and the ciphertext.

(cryptography) A basic component of symmetric-key algorithms, which performs substitution, transforming one set of bits into another.


trust anchor

(cryptography) An authoritative entity that is assumed to be trustable.


SHA

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-SHA.wav

Secure Hash Algorithm
w:Secure Hash Algorithms

(cryptography) Acronym of Secure Hash Algorithm.


cold boot attack

cold boot attack (plural cold boot attacks)

(cryptography) A type of sidechannel attack in which somebody with physical access to a computer is able to retrieve encryption keys from a running operating system after a reboot. It relies on the fact that the contents of memory can still be read for a short period after power is cut off.


self-signed

(computing, cryptography) Of a security certificate: signed by the same entity whose identity it certifies; signed with its own private key.


self-signing

(computing, cryptography) The use of self-signed security certificates.


cryptoworm

(cryptography, computer security) A form of malware that spreads in the form of a worm and encrypts victims' data.


Threefish

From three + fish, modelled on the earlier Twofish.

(cryptography) A symmetric-key tweakable block cipher involving the Skein hash function.


HMAC

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-HMAC.wav

hash-based message authentication code
w:HMAC

(cryptography) Initialism of hash-based message authentication code, a specific type of the message authentication code (MAC) involving a cryptographic hash function and a secret cryptographic key.


HAIFA

(cryptography) Abbreviation of hash iterative framework: a cryptographic structure used in the design of hash functions.


nothing-up-my-sleeve number

nothing-up-my-sleeve number (plural nothing-up-my-sleeve numbers)

In reference to magic tricks in which the performer may have something concealed in a sleeve (or may demonstrate to the audience that they do not).

The key schedule, however, expanding the key using an essentially one-way method, is more complex, with the binary expansions of both e and the golden ratio of "nothing up my sleeve numbers".

2014 May 2, Mr. Ajay Bhaisare, “Data Protection Outsourcing of Cloud Data to Maintain Trust between Cloud Service and Data Owner Using RC5 Algorithm”, in IJCSMC, volume 3, number 5, page 608:

Anyway, they make the same point: “The BADA55-VPR curves illustrate the fact that 'verifiably pseudorandom' curves with 'systematic' seeds generated from 'nothing-up-my-sleeve numbers' also do not stop the attacker from generating a curve with a one-in-a-million weakness.”

(cryptography) A number which, by its construction, is above suspicion of having hidden properties; used in creating cryptographic functions such as hashes and ciphers.


polynomial basis

polynomial basis (plural polynomial bases)

When using polynomial bases, the first stage in computing the product of two elements of #92;mathbbF#95;#123;2ⁿ#125; is the multiplication of two polynomials of degree at most n-1 in #92;mathbbF#95;2#91;x#93;.

1999, I. Blake, G. Seroussi, N. Smart, Elliptic Curves in Cryptography, Cambridge University Press, page 20:

2010, Vladimir Tujillo-Olaya, Jaime Velasco-Medina, Hardware Architectures for Elliptic Curve Cryptoprocessors Using Polynomial and Gaussian Normal Basis Over GF(2²³³), Marina L. Gravrilova, C. J. Kenneth Tan, Edward David Moreno (editors), Transactions on Computational Science XI: Special Issue on Security in Computing, Part 2, Springer, LNCS 6480, page 79,
In this case, the GF(2ᵐ) multiplication is implemented in hardware using three algorithms for polynomial basis (PB) and three for gaussian normal basis (GNB).

In contrast to the case of normal bases considered in Theorem 5.1.9, the dual basis of a polynomial basis is usually not a polynomial basis.
[…]
5.1.13 Theorem [1265, 1298] Let #92;theta be a root of a monic irreducible polynomial f of degree m over K#61;#92;mathbbF#95;q, and let B#61;#92;#123;1,#92;theta,#92;theta²,#92;dots#92;theta#123;m-1#125;#92;#125; be the corresponding polynomial basis of F#61;#92;mathbbF#95;#123;qᵐ#125; over K. Then the dual basis B#42; of B is a polynomial basis if and only if f is a binomial and m#92;equiv 1#92;#33;#92;#33;#92;#33;#92;#33;#92;pmodp, where q is a power of the prime p.
5.1.14 Corollary There exists a dual pair of polynomial bases of #92;mathbbF#95;#123;qᵐ#125; over #92;mathbbF#95;q if and only if the following three conditions are satisfied:[…].

2013, Gary L. Mullen, Daniel Panario, Handbook of Finite Fields, Taylor & Francis (Chapman & Hall / CRC Press), page 103:

primitive polynomial
primitive polynomial

(algebra, field theory, cryptography, of a finite field) Specifically, a basis, of the form {1, α, ..., αⁿ⁻¹}, of a finite extension F_(qⁿ) of a Galois field F_q, where α is a primitive element of F_(qⁿ) (i.e., a root of a degree-n primitive polynomial over F_q).


DSA

Digital Signature Algorithm
w:Digital Signature Algorithm

(cryptography) Initialism of Digital Signature Algorithm.


permutation box

permutation box (plural permutation boxes)

(cryptography) A method of permuting or transposing bits (binary digits) across S-box inputs while retaining diffusion.


Shannon's maxim

Kerckhoffs's principle
Kerckhoffs's principle

(cryptography) "The enemy knows the system" — a restatement of Kerckhoffs's principle.


black room

(cryptography) A governmental facility for intercepting and decrypting communications.


subround

(cryptography) A subsidiary stage of encryption, part of a round.


PoW

PoW (countable and uncountable, plural PoWs)

With PoW, as new, unverified transactions become available or broadcast to the entire blockchain network, each node that maintains a copy of the ledger (also known as a “miner”) verifies a set of those transactions to prevent so called “double spending”.

2019, Peng Zhang, Role of Blockchain Technology in IoT Applications, Academic Press, →ISBN, page 187:

(countable and uncountable, cryptography, cryptocurrencies) Initialism of proof of work.


proof of work

proof of work (countable and uncountable, plural proofs of work)

proofs of work (plural)
proof-of-work (alternative)

The network timestamps transactions by hashing them into an ongoing chain of hash-based proof-of-work, forming a record that cannot be changed without redoing the proof-of-work.

2008 October 31, Satoshi Nakamoto, “Bitcoin: A Peer-to-Peer Electronic Cash System”, in metzdowd.com Cryptography Mailing List:

Blockchains that use “proof-of-work”, as many popular cryptocurrencies do, raise yet another problem: they require a huge amount of raw energy to secure them.

2018 March 5, Nouriel Roubini, Preston Byrne, “Bitcoin is based on the blockchain pipe dream”, in The Guardian:

(cryptography, cryptocurrencies) A form of cryptographic proof in which a prover proves to verifiers that a certain amount of a specific computational effort has been expended.


KDF

key derivation function
w:key derivation function

(cryptography) Initialism of key derivation function.


ciphertext-only attack

ciphertext-only attack (plural ciphertext-only attacks)

known-plaintext attack
known-plaintext attack

(cryptography) An attack on a cryptosystem that relies only on the attacker's knowledge of some ciphertexts encrypted with that system and key. Less powerful than a known-plaintext attack.


known-plaintext attack

known-plaintext attack (plural known-plaintext attacks)

ciphertext-only attack
ciphertext-only attack

chosen-plaintext attack
chosen-plaintext attack

(cryptography) An attack on a cryptosystem that relies on the attacker's knowledge of not just some ciphertexts encrypted with that system and key, but also their corresponding plaintexts (cribs). More powerful than a ciphertext-only attack, but less powerful than a chosen-plaintext attack.

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chosen-plaintext attack

chosen-plaintext attack (plural chosen-plaintext attacks)

chosen-ciphertext attack
chosen-ciphertext attack

(cryptography) An attack on a cryptosystem that relies on the attacker's ability to choose any plaintext of their liking and encrypt it into the corresponding ciphertext with that system and key. More powerful than a known-plaintext attack but less powerful than a chosen-ciphertext attack.

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chosen-ciphertext attack

chosen-ciphertext attack (plural chosen-ciphertext attacks)

The ElGamal encryption system is resistant against chosen-plaintext attacks, but not against chosen-ciphertext attacks.

(cryptography) An attack on a cryptosystem that relies on the attacker's ability to choose any ciphertext of their liking and decrypt it into the corresponding plaintext with that system and key. More powerful than a chosen-plaintext attack.

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collision attack

collision attack (plural collision attacks)

(cryptography) An attack on a cryptographic hash function that is able to find a hash collision (a pair of different inputs that have the same hash) faster than by brute force.


preimage attack

preimage attack (plural preimage attacks)

(cryptography) An attack on a cryptographic hash function that is able to find a preimage for a hash; that is, it is able to determine (faster than by brute force) some input that results in a known hash when passed through the algorithm.


second preimage attack

second preimage attack (plural second preimage attacks)

second preimage attacks (plural)
second-preimage attack (alternative)

(cryptography) An attack on a cryptographic hash function that is able to find a second preimage for a hash and its preimage; that is, given a hash and an input that has that specific hash, it is able to find (faster than by brute force) another input with the same hash.


elliptic-curve cryptography

(cryptography) A branch of public-key cryptography in which elliptic curves are used to generate key pairs.


rotor machine

(cryptography) An mixed electronic and mechanical stream cipher composed of a series of wheels, widespread use from the 1920s–1970s.


cryptojack

en-verb

cryptojack (third-person singular simple present cryptojacks, present participle cryptojacking, simple past and past participle cryptojacked)

cryptojacks (present singular third-person)
cryptojacking (participle present)
cryptojacked (participle past)
cryptojacked (past)

(cryptography, computer security) To make unauthorized use of an individual's electronic device to mine for cryptocurrency.


SPN

service principal name
service principal name#English

(computing, cryptography) Abbreviation of service principal name.


keysigning

(cryptography) The process of digitally signing someone else's public key using one's own.


codetext

To work well, a code must have thousands of plaintext words or phrases with a codetext equivalent for each. Usually, for the sake of manageability, a codetext word is limited to three to five letters or numbers. All the codetexts and their plaintext meanings are listed in a codebook.

1974, The Family Creative Workshop, Plenary Publications International:

The repetitions of the codetext matched those of the proposed plaintext perfectly.[…]The two spent the morning inserting his equivalents into the codetexts, but none stood close enough together in the texts to obtain confirmation through new identifications.

2004, David Kahn, “Yardley’s Triumph”, in The Reader of Gentlemen’s Mail: Herbert O. Yardley and the Birth of American Codebreaking, New Haven, Conn., London: Yale University Press, page 67:

DNA encryption of images, part 1: Alice uses her library of primers to make codetextᶜ-plaintextᶜ pairs.[…]The result of adding the whole library to the long DNA, letting the copying happen, and then dissociating the copied DNA from the original is that Alice will have a collection of plaintextᶜ-codetextᶜ pairs, the codetextᶜ being photosensitive (the superscript c indicates a strand complementary, so able to bind to the original DNA). Alice then adds her mixture of plaintextᶜ-codetextᶜ pairs to her chip, and the strands will hybridize to the complementary, immobile strands on the chip.

2018, Jamie A. Davies, “Synthetic biology for engineering”, in Synthetic Biology: A Very Short Introduction, Oxford University Press, page 82:

(cryptography) An encoded form of a message, as opposed to plaintext.


Coppersmith method

the Coppersmith method (canonical)
Coppersmith's method (alternative)

Coppersmith's attack
Coppersmith's attack

(mathematics, cryptography) A method of finding small integer zeros of univariate or bivariate polynomials modulo a given integer. It forms the basis of Coppersmith's attack.


Coppersmith's attack

(mathematics, cryptography) A kind of cryptographic attack on the RSA cryptosystem, based on the Coppersmith method.


Party B

(cryptography) Synonym of Bob (“placeholder”).


Party A

(cryptography) Synonym of Alice (“placeholder”).


trustlet

(computing, cryptography) A trusted process or application in certain types of secure system.


homomorphic encryption

en-noun

homomorphic encryption (usually uncountable, plural homomorphic encryptions)

In 2010, Nigel P. Smart and Frederik Vercauteren presented a fully homomorphic encryption scheme with smaller key and ciphertext sizes.

2014, Xun Yi, Russell Paulet, Elisa Bertino, Homomorphic Encryption and Applications, Springer, →ISBN, page 50:

As mentioned before, homomorphic encryption is adopted in our auction design. Homomorphic encryption is used when there is a requirement to perform certain operations while the inputs are not disclosed.

2020, Haya Shajaiah, Ahmed Abdelhadi, Charles Clancy, Performance and Security for the Internet of Things […] , McGraw Hill, →ISBN, page 101:

(cryptography) A form of encryption that permits users to perform computations on its encrypted data without first decrypting it.


DPV

delegated path validation
w:delegated path validation

(cryptography) Initialism of delegated path validation.


classical cipher

classical cipher (plural classical ciphers)

(cryptography) A cryptographic algorithm was used historically and are easy to solve by hand or using modern technology.


SNARG

2018, Dan Boneh, Yuval Ishai, Amit Sahai, David J. Wu, Quasi-Optimal SNARGs via Linear Multi-Prover Interactive Proofs, Jesper Buus Nielsen, Vincent Rijmen (editors), Advances in Cryptology – EUROCRYPT 2018: 37th Annual International Conference on Cryptographic Techniques, Proceedings, Part III, Springer, LNCS 10822, page 224,
A SNARG is publicly verifiable if anyone can verify the proofs, and it is designated-verifier if only the holder of a secret verification state (generated along with the CRS) can verify proofs.

However, SNARGs and SNARKs (blockchain implementations of SNARGs) rely on pre-quantum assumptions and are not post-quantum secure. Hence, lattice-based SNARGs are proposed (Boneh et al., 2017).

2020, Melanie Swan, Renato P Dos Santos, Frank Witte, Quantum Computing, World Scientific, page 172:

2021, Yael Taumann Kalai, Vinod Vaikuntanathan, Rachel Yun Zhang, Somewhere Statistical Soundness, Post-Quantum Security, and SNARGs, Kobbi Nissim, Brent Waters (editors), Theory of Cryptography: 19th International Conference, TCC 2021, Proceedings, Part I, Springer, LNCS 13042, page 355,
In this section, we construct SNARGs for languages with a (computational) non-signaling mathsf PCP, assuming the existence of a SNARG for mathsf BatchNP.

(computing, cryptography) Acronym of succinct non-interactive argument.


SNARK

2019, Anca Nitulescu, Lattice-Based Zero-Knowledge SNARGs for Arithmetic Circuits, Peter Schwabe, Nicolas Thériault (editors), Progress in Cryptology – LATINCRYPT 2019: 6th International Conference, Proceedings, Springer, LNCS 11774, page 223,
SNARG vs. SNARK. If we replace the computational soundness with computational Knowledge Soundness we obtain what we call a SNARK, a succinct non-interactive argument of knowledge.

2020, Fuyuki Kitagawa, Takahiro Matsuda, Takashi Yamakawa, NIZK from SNARG, Rafael Pass, Krzysztof Pietrzak (editors), Theory of Cryptography: 18th International Conference, Proceedings, Part I, Springer, LNCS 12550, page 568,
Actually, what is often used in blockchains is a SNARK [4], which is a stronger variant of a SNARG that satisfies extractability.

2023, Matteo Campanelli, Chaya Ganesh, Hamidreza Khoshakhlagh, Janno Siim, Impossibilities in Succinct Arguments: Black-Box Extraction and More, Nadia El Mrabet, Luca De Feo, Sylvain Duquesne (editors), Progress in Cryptology - AFRICACRYPT 2023: 14th International Conference, Proceedings, Springer, LNCS 14064, page 467,
Whether we can build SNARKs with black-box extraction in the standard model is an elusive problem. […] In particular, we show that a SNARG can be lifted to a SNARK with the features above for the class of languages FewP (roughly, NP with polynomial many witnesses).

succinct non-interactive argument of knowledge#English

(computing, cryptography) Acronym of succinct non-interactive argument of knowledge.


bifid cipher

Coordinate term: trifid cipher

(cryptography) A classical cipher that combines the Polybius square with transposition, and uses fractionation to achieve diffusion.


trifid cipher

Coordinate term: bifid cipher

(cryptography) A classical cipher that extends the earlier bifid cipher with the use of trigrams.


pattern word

(cryptography) A word in which some letter appears more than once, useful in solving a cryptogram.


pigpen cipher

(cryptography) A geometric simple substitution cipher, which exchanges letters for symbols which are fragments of a grid.


unsteckered

From un- + German Stecker (“plug”) + -ed.

(cryptography) unprocessed by a plugboard.


steckered

(cryptography) Processed by a plugboard.


rail fence cipher

rail fence cipher (plural rail fence ciphers)

(cryptography) A transposition cipher in which the plain text is written in a zigzag fashion diagonally up and down on successive "rails" of an imaginary fence, and then the characters are read off in rows to obtain the ciphertext.


Nihilist cipher

Nihilist cipher (plural Nihilist ciphers)

The cipher was originally used by Russian Nihilists in the 1880s to organise terrorism against the tsarist regime.

(cryptography, historical) A symmetric cipher in which a Polybius square using a mixed alphabet is used to convert both the plain text and a keyword to a series of two-digit numbers, which are then summed in the normal way to get the ciphertext, with the key numbers repeated as required; (by extension) any of several improved algorithms based on this.


forty weepy weepy

From a message whose plaintext began fortyweepyyweepy: German fort (“forth”), short for Fortsetzung (“continuation”) + weep, typewriter code for 23:30, the time of the previous message. Enigma machines had no number keys, so the letter y marked the letters to be interpreted as numbers.

(cryptography, historical) Cryptanalysis of an Enigma message which was a continuation of a previous message sent at a known time.


passive attack

(cryptography) An attack in which the cryptanalyst cannot interact with any of the parties involved, attempting to break the system solely based upon observed data such as ciphertext.


GMAC

Galois Message Authentication Code
w:Galois Message Authentication Code

(cryptography) Acronym of Galois Message Authentication Code.


mixed alphabet

(cryptography) The mapping from plaintext to ciphertext characters in a substitution cipher, when it is not merely a shift or reversal but an arbitrary reordering.


password wallet

password wallet (plural password wallets)

I believe Mozilla 5 (to be released as Netscape 6) also has a password "wallet" feature. Not sure about other vendors.

2000 March 16, Peter W, “allowing directory access for authorized users”, in comp.infosystems.www.servers.unix (Usenet):

Instead, the individual passwords are generated algorithmically from the master password and the sites’ names. As an advantage compared with a password wallet, nothing at all needs to be stored on the client machines. As a disadvantage, there is no easy way to change the master password.

2007, Max Hailperin, Operating Systems and Middleware: Supporting Controlled Interaction, Thomson Course Technology, page 405:

The two main things to remember with a password wallet is to have a very secure unique password or passphrase to access the wallet, and keep a secure record of the password or passphrase,[…]

2017, Graham Day, Security in the Digital World: For the home user, parent, consumer and home office, Walter de Gruyter GmbH, page 111:

He showed Gemma the files to read and unlocked his password wallet. "The password wallet isn't very secure." "More secure than my physical diary which I'm sure has been checked.[…]"

2017, Ray McCarthy, The Solar Alliance, Corvids Press, page 154:

The user must have access to the password wallet whenever she needs a password.

2018, Matt Bishop, Computer Security: Art and Science, Pearson Education, page 523:

In this section, we adapt our OTP wallet construction to the proof-of-stake setting (the password wallet can also be adapted likewise).

2023, Shin'ichiro Matsuo, Lewis Gudgeon, Ariah Klages-Mundt, Daniel Perez Hernandez, Sam Werner, Thomas Haines, Aleksander Essex, Andrea Bracciali, Massimiliano Sala, editors, Financial Cryptography and Data Security. FC 2022 International Workshops: CoDecFin, DeFi, Voting, WTSC, Grenada, May 6, 2022, Revised Selected Papers, Springer International Publishing, page 632:

(computing, cryptography) An application or mechanism which stores someone's passwords by encryption.


patristocrat

Coordinate term: aristocrat

(cryptography) A cipher in which punctuation and word spacing are not retained.


transposition cipher

transposition cipher (plural transposition ciphers)

(cryptography) An encryption method that rearranges the order of the plaintext letters.


stegotext

(cryptography) A text that contains a secret subtext encoded via steganography.


covertext

(cryptography) A seemingly innocuous text that contains a secret text encoded within it.


truststore

certificate authority
certificate authority

(cryptography) A storage area for trusted cryptographic certificates issued by a certificate authority.


CRQC

It's almost like the NSA is dropping a not-so-subtle hint, though why it would is debatable. If it has a CRQC, or is on the path to one, it might want to warn allies, vendors, and citizens to think about using quantum-resistant technologies in case bad people develop a CRQC too. But why would the spies tip their hand so? It's all very curious.

2021 September 1, Gareth Corfield, “NSA: We 'don't know when or even if' a quantum computer will ever be able to break today's public-key encryption”, in The Register, archived from the original on 2024-05-18:

Shor's algorithm
Shor's algorithm#Proper noun

(cryptography) Initialism of cryptographically relevant quantum computer; a quantum computer powerful enough to break modern cryptography (e.g., using Shor's algorithm to break RSA or Ed25519).


digital signatures
digital signature#Noun

(cryptography) An algorithm, based on the properties of elliptic curves, used to securely create digital signatures.


Jefferson disk

Commonly attributed to Thomas Jefferson.

(historical, cryptography) Any of a set of stackable disks, each having the letters of the alphabet arranged in some sequence around its edge, used in a cipher system.