Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange


A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.

× 158
the study of the properties and construction of numbers, particularly integers. Prime numbers are of particular interest to number theorists and consequently cryptographers as they ar…
× 157
Questions about formal definitions of "security" for various cryptographic schemes (e.g. perfect secrecy, semantic security, ciphertext indistinguishability, etc.)
× 146
the detailed analysis of the security of an abstract or concrete cryptographic protocol.
× 141
unique (usually random) data passed into a hash function for password storage to avoid the possible usage of rainbow tables or similar attacks. Salt will not help against dictionary or brute f…
× 141
The attacker knows at least one sample of both the plain text and the cipher text.
× 136
Irreversibly converting user-selected passwords into authentication tokens that can be safely stored e.g. in a user database. Typically done with a salted password-based key derivation function (PBKDF…
× 129
an attack model for cryptanalysis in which the cryptanalyst gathers information, at least in part, by choosing a ciphertext and obtaining its decryption under an un…
× 122
Confidentiality in a very strong sense. Ciphers reaching perfect-secrecy can't be broken to disclose informations over the plaintext from the ciphertext, even with unlimited computing power. The most …
× 118
Hash-based digital signatures, such as Lamport one-time signatures, are digital signature schemes based on a (non-trapdoor) one-way function such as a cryptographic hash. Such schemes are expected to …
× 117
attacks using information leaked by implementations of cryptographic algorithms to obtain information about keys or (plaintext) data, instead of (or additional to) using cryptographic weaknesses.
× 117
The process of encrypting individual files on a storage medium and permitting access to the encrypted data only after proper authentication is provided.
× 116
an encryption algorithm which works by replacing plaintext units with corresponding ciphertext units, following some rule depending on the key.
× 112
a digital currency powered by cryptography. This tag is applicable only to Q&As about the cryptographic mechanisms used by a currency, not for questions about economy, usage, or ac…
× 108
Encryption using a key derived from a password or passphrase entered by the user.
× 106
Difficulty of finding an input string that hashes to a given value
× 105
a mode of operation for a block cipher, with the characteristic that each possible block of plaintext has a defined corresponding ciphertext value and vice versa.
× 105
an arbitrary number or string used only once within the context of a specific cryptographic scheme. Nonces are used e.g. in authentication protocols to prevent replay attacks, as well as …
× 103
A way, esp. one of several possible variations, in which a set or number of things can be ordered or arranged.
× 102
a cryptographic hash function standardized by NIST as a new alternative to the SHA-2 hash function family.
× 100
Cryptographic hardware enables the handling of cryptographic tasks and/or problems using hardware instead of software solutions.
× 100
A public-key cryptosystem invented by Pascal Paillier in 1999.
× 99
a family of cryptographic hash functions designed by the NSA and published by NIST in 2001. The family includes various output lengths (224, 256, 384, and 512 bits).
× 99
The National Institute of Standards and Technology (NIST) is a U.S. federal agency that works with industry to develop and apply technology, measurements, and standards.
× 98
an algorithm for producing digital signatures. The algorithm is based on Edwards curves introduced by Bernstein et al. (2007) and named after mathematician Harold M. Edwards.
× 98
a function that cannot be distinguished (with practical effort) from a permutation selected at random with uniform probability from the family of all permutations …
× 97
In a cryptographic sense, integrity means unimpaired and complete.
× 96
a protocol where one party commits themselves to a secret value without revealing it. At a later point, the value can be revealed.
× 95
Linear Feedback Shift Register, a pseudorandom bit generator which can be efficiently implemented in hardware.
× 93
Quantum cryptography describes the use of quantum mechanical effects to perform cryptographic tasks. This is not to be confused with quantum computing or cryptanalysis techniques such as Shor's algori…
× 92
Performance defines the abilities of a cipher in terms of processing throughput on various platforms, including its memory requirements.
× 91
a structure that has been used to create a number of different block ciphers (e.g., DES, Blowfish, Twofish, RC6).
× 90
A model used in cryptographic security proofs, in which concrete primitives such as hash functions are replaced with a "random oracle": a hypothetical black box that maps its inputs to truly random ou…
× 88
a fast and simple stream cipher used correctly in SSL and incorrectly in WEP.
× 85
a family of symmetric block-ciphers with block and keys sizes of 128, 160, 192, 224, or 256 bits.
× 85
a method of building a message authentication code from a block-cipher.
× 85
a type of public-key encryption in which the key used for encryption is based on selected attributes of the readers. Decryption of the ciphertext is possible only if the …