Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [terminology]

Questions about the meaning and proper use of specific technical terms or notation within cryptography.

Terminology describes the vocabulary of technical terms used in a particular field or on a specific subject; in this case: cryptographic terms… which frequently overlap with scientific terms.

368 questions
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What is the main difference between a key, an IV and a nonce?

What are the main differences between a nonce, a key and an IV? Without any doubt the key should be kept secret. But what about the nonce and the IV? What's the main difference between them and their purposes? Is it only that, in literature and in…
curious
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What are the differences between .pem, .csr, .key, .crt and other such file extensions?

I'm new to SSL / TLS, and I want to work with the OpenSSL toolkit. What do .pem and .csr stand for? I do know that .key is the private key and .crt is the public key.
Richard R. Matthews
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101
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What is the difference between a digest and a hash function?

I was wondering about the difference between these two terms... What is the difference between a digest and a hash function?
Francesco Mari
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Layman's explanation of encryption backdoors

In the media, I sometimes read about "backdoors" in encryption algorithms. I'd like to understand what such a backdoor actually consists of. Is it: a) a hidden weakness in the math formulas that can cause security to be broken by brute force in a…
forthrin
75
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1 answer

Easy explanation of "IND-" security notions?

There are many schemes that can advertise themselves with certain security notions, usually IND-CPA or IND-CCA2, for example plain ElGamal has IND-CPA security but doesn't provide IND-CCA security. The most common ones are the "IND-" ones,…
SEJPM
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62
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Definition of textbook RSA

What is the definition of textbook or "raw" RSA? What are some of the properties of textbook RSA? How does it differ from other schemes based on RSA?
Bobby S
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56
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Kerckhoffs’ principles – Why should I make my cipher public?

As I understand it, the less people know about the internals of my protocol or cipher, the more secure the protocol is. However Kerckhoffs's principle states that A cryptosystem should be secure even if everything about the system, except the key,…
rath
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51
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Differences between the terms "pre-master secret", "master secret", "private key", and "shared secret"?

Both crypto.SE and security.SE have excellent Q&As about how TLS generates session keys (I have linked some at the bottom). In reading these threads I'm having troubles with terminology since the following terms seem to be used with overlapping…
Mike Ounsworth
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51
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What are SNARKs?

What does it mean and what is it used for, I have been hearing this term a lot lately. From the context I've heard it talked about it seems to be connected with zero knowledge?
wi1
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What are the differences Between “White-Box Cryptography” and “Code Obfuscation”?

I have been reading the question "What is a white-box implementation of a cryptographic algorithm?" and it led to this short article / Q&A which states in question 2: Q2: What is the difference with code obfuscation? Related and complementary…
MByD
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What is a "freestart collision"?

In their work on SHA-1 collisions (cf. the EUROCRYPT-2016 paper “Freestart collision on full SHA-1” by Stevens, Karpman, and Peyrin) Stevens et al show that they are able to generate "freestart collisions" on SHA-1. They say: Even though freestart…
otus
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What is the difference between CSPRNG and PRNG?

What is the difference between CSPRNG and PRNG? Is there performance differential between them? For example: We use PRNG for key generation which is very expensive and CSPRNG for IV/nonce in block ciphers which is fast? What is the difference…
randomness
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8 answers

Simply put, what does “perfect secrecy” mean?

I would like to ask for a clear (but maybe not so deep) explanation of what the term "perfect secrecy" means. As far as I have researched and understood, it has to do with probabilities of assuming that a certain variable will be the key for a…
Emyr
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What is Attribute Based Encryption?

Can someone explain what attribute based encryption is? I was searching for a book or something that can help me in this regard but so far I have found none. Google also returns practically nothing aside from the papers.
Mark
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What is “Fast Prime”?

In this note, the manufacturer of a RSA key generation gizmo vulnerable to the new ROCA attack (see second section) explains that it is common practice to employ acceleration algorithms in order to generate key pairs, especially if time resources…
fgrieu
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