Questions tagged [terminology]

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

Filter by
Sorted by
Tagged with
2
votes
2answers
48 views

Is Keystore a file, a database, a specification?

What exactly are keystores? I understand they are used to store things like private keys, certificates etc. But how exactly is that done? Is it just an encrypted databases where you put all these ...
0
votes
1answer
53 views

What is the term to describe the combination of ciphertext, IV and authentication tag?

Authenticated encryption with associated data, such as AES-GCM, will take as input: IV, optional associated data, plaintext and key. A ciphertext and an authentication tag will be produced. Is there a ...
3
votes
1answer
322 views

What does it mean: Hardware vs software implementation of a cryptosystem

While reading some cryptography papers, I passed by some new terms like the hardware and software implementation of encryption systems. The question: what are the hardware and the software ...
1
vote
1answer
51 views

How do we say that one cryptographic primitive is stronger than another?

Can anyone help me understand this: How do we say that one cryptographic primitive is stronger than another?
1
vote
1answer
191 views

One way function existence

Let $x = (x_1, x_2,...,x_n)\in\{0,1\}^n$ for $n\in\mathbb{N}$. Prove that if one-way functions (OWFs) exist, then there exists a one-way function $f$ such that for every bit $i\in[1,n]$ there exists ...
0
votes
2answers
89 views

What exactly is asymmetric about 'asymmetric cryptography'?

What exactly is asymmetric about 'asymmetric cryptography'? https://www.sysadmins.lv/blog-en/digital-signatures.aspx says: "In other words, anything that is encrypted by a public key can be ...
1
vote
1answer
70 views

What is a clearsigned message?

PGP Digital Timestamping Service webpage mentions The service operates in a number of different "modes" depending upon the required results. The current modes are:- ...
0
votes
1answer
67 views

What does this Big-O notation mean based on appendix?

I am reading the following book: Introduction to Modern Cryptography Second Edition by Jonathan Katz and Yehuda Lindell. I am going through page 533 where they list what some of the notation means, ...
3
votes
3answers
167 views

Measuring entropy of a uniform distribution source

What is entropy? I do not understand it at all. One article states: When there is an equal chance for all items to appear, we have a uniform distribution. In uniform distribution the entropy is high....
1
vote
0answers
43 views

Question about hiding commitment scheme for integers

Given a generic group $\mathbb{G}$ of an unknown order (such as a $3000$-bit RSA group) and a randomly generated element $g \in \mathbb{G}$, is the commitment scheme $\mathrm{Com}(x)= g^x$ not ...
10
votes
4answers
2k views

Does a hash function necessarily need to allow arbitrary length input?

I always assumed that a hash function allows input of arbitrary length, since that's what all the hash functions I was aware of did. Wikipedia's definition of a hash function is as follows: A hash ...
1
vote
1answer
73 views

What is the more accurate way of stating the correctness of a PK encryption scheme?

Is it more accurate to state that a public key encryption scheme is correct if for all $m \in M$ and $(pk, sk) \in \operatorname{Gen}(1^k)$ a. $\operatorname{Dec}_{sk}(\operatorname{Enc}_{pk}(m))=m\;$ ...
0
votes
2answers
216 views

There is Alice and there is Bob. But what is the name of the malicious user?

I know it is a kinda funny and maybe even naive question but its still security related, so I decided to ask. Bob and Alice are widely used names indicating the two end-users/parties for web protocols....
7
votes
1answer
455 views

What does it mean to be "sound"?

I've been reading this in many places and I still don't properly understand what it means to be "sound". As an example of what I am asking for: The Fiat-Shamir transfrom is sound in the ...
5
votes
4answers
244 views

What does perfect mean within perfect forward secrecy and why do some cryptographers disagree with the term?

In this blog post, Matthew Green says Forward secrecy (usually misnamed “perfect forward secrecy”)... The Wikipedia article on forward secrecy (which the same sentence links to in the blog) says ...
1
vote
2answers
389 views

Is it fair to say that MACs use a signing algorithm?

The Wikipedia page on MAC calls the algorithm that is used to generate the MAC as a signing algorithm. Is that a fair use of that term? Can we then say that HMAC-SHA-1 uses SHA-1 as the signing ...
3
votes
0answers
54 views

What is the fundamental difference between multipartite and multilevel secret sharing?

According to this paper , Multipartite secret sharing scheme is a scheme in which the set of participants is divided into disjoint parts and all participants in the same part play an equivalent role ...
4
votes
2answers
153 views

What is the difference between security parameter and $b$-bit security?

In a previous question, I read ... for $b$-bit security meaning $O(2^b)$ work for an attacker to break the system... While in Katz's Introduction to modern Cryptography, I read: The key-generation ...
2
votes
2answers
373 views

Difference between computationally and perfectly hiding (binding) properties

I am new to Cryptography and has a trouble of understanding the difference between perfect and computationally hiding (binding) properties of a commitment scheme. I also would like to ask what does it ...
0
votes
2answers
45 views

What is the difference between an encryption protocol and an encryption standard?

What is the difference between an encryption protocol and an encryption standard? Am I missing something here? Or are they in fact two different concepts altogether?
3
votes
2answers
143 views

Short term for "Purposely-slowed hash"

When Argon2, Balloon, scrypt, bcrypt¹, PBKDF2… are used for a password, we can call them password hash (for password storage) or password-based key derivation function (for use in encryption). But ...
5
votes
2answers
1k views

What is the difference between data compression and compression in cryptographic algorithms?

What is the differences between data compression as used in e.g. the ZIP protocol and compression as performed in cryptographic hashes? Are there common properties as well, apart from creating a ...
0
votes
0answers
36 views

What does it mean exactly that an adversary can control a polynomial number of parties?

I have an intuitive idea of this, but I am not sure if I am formally interpreting it correctly. In the scenario I am considering, each party is identified by a sequence of $n$ bits and I have $2^{n}$ ...
5
votes
2answers
1k views

Meaning of the term "Key Material"

I am reading specifications from my client that focuses on the topic of security. In these specs, the term key material has appeared many times. I used Google to look for what the term means. ...
1
vote
0answers
62 views

Function secret sharing and sharing a truth table

I was reading a paper (Function Secret Sharing by Boyle, Gilboa and Ishai, PDF) on Function Secret Sharing and in that the author talked about a naive construction of a p party DPF wherein the truth ...
0
votes
1answer
378 views

What is the definition of dummy password?

Recently, I try to read some papers about Password Authenticated Key Exchange (PAKE). I can’t understand the meaning of “dummy password .” Can someone gives a concrete definition of it. And what is ...
0
votes
2answers
358 views

is it necessary to write C=E(K,P), Can we write C=E(P,K)?

I just want to know that can we write encryption and decryption formula like $C=E(P,K)$ instead of $C=E(K,P)$
3
votes
1answer
758 views

What is Post-Compromise security exactly?

After reading these papers on Post-Compromise Security: Post Compromise Security Asynchronous Ratcheting Trees My understanding is the following: it is possible for a key-agreement protocol to ...
3
votes
1answer
124 views

I don't understand the definition of monotonic access structures

I am very confused with definition 1 in section 2.1 of this article. Definition 1 (Access Structure [2]) Let $\left\{ P_1, P_2, ..., P_n \right\}$ be a set of parties. A collection $\mathbb{A} \...
2
votes
2answers
125 views

Is there a term for cryptographic attacks where you can verify decryption without assuming any known structure on the plaintext?

The questions https://security.stackexchange.com/questions/1696/if-someone-breaks-encryption-how-do-they-know-theyre-successful and https://security.stackexchange.com/questions/119887/how-to-know-if-a-...
3
votes
1answer
871 views

What does "crypto_box" actually mean in libsodium and NaCl?

I cannot find what "crypto_box" actually means. In general, and in specific cases, what does "box" do? I know that libsodium is authenticated encryption, but GPG is not. "Box" makes me think the ...
2
votes
1answer
100 views

Meaning of difference Δ delta

I tried to understand some crypto text but I am new to this. Does this: Let $X,X'$ be $\ell$-bit values, and $\Delta X=X\oplus X'$ means that $X$ and $X'$ have $\ell$ bits and $\Delta X=X-X'$ or ...
1
vote
1answer
33 views

Terminology for parties in authentication protocols

Is there a common terminology to designate parties in authentication protocols? For example, we typically use prover and verifier to designate parties with zero-knowledge proofs.
1
vote
1answer
75 views

Confused about terminology in the many flavors of security [closed]

I am learning about cryptography from diverse sources, and I have found terminology a bit confusing. In principle, I understand the difference between the symbolic model and the computational model. ...
6
votes
2answers
203 views

What does the term "differential" in "differential privacy" mean?

I'm new in Differential Privacy (DP) and I have two questions: Why do we have the term differential in differential privacy? Are The local and global differential privacy and global and local ...
6
votes
3answers
229 views

Would creating a custom human language be stronger protection than encrypting a known human language?

There are some languages that people haven't been able to read (Cretan Hieroglyphics for example). Does that mean that you can better protect data by making your own language than by encrypting an ...
1
vote
1answer
270 views

What's the difference between threshold signatures and multisignatures?

I was wondering what's the difference between threshold signatures and multisignatures. In what respects do they differ? For example, is n-out-of-n threshold signature, just a multisignature?
5
votes
2answers
2k views

Key Exchange vs Key Encapsulation

From what I understand, the steps of a key exchange protocol are Alice and Bob each encrypt something using their public key and private key and send the result to each other Alice and Bob each do ...
1
vote
1answer
109 views

Difference between Verification and Public Key for Signature Schemes

This is a semantics Question. Typically, in many asymmetric schemes, for this question specifically, digital signatures, we see that designers describe the key given to the verifier as Public Key. ...
0
votes
1answer
121 views

What does it mean for a number to be “in the order of” a prime number?

In some papers I'm looking at there is some language that says things like "Choose a random number in the order of prime q" and I see some syntax that it is referring to that looks s = Zq (...
5
votes
3answers
904 views

In laymans terms, what exactly is a "One time pad"?

Background I am an undergraduate novice learning about cryptography. Recently my professor introduced us to the concept of a "One time pad". According to my professor: A one time pad is a cipher ...
0
votes
0answers
34 views

Question about terminology of public key encryption in practice

I am asking myself the following question: Say Alice sets all things up so that she is the reciever in an RSA-system. What do you call this "network" now? I hope it is clear what I mean. I ...
0
votes
1answer
97 views

Termonology help: What is using AEAD without encrypting data called?

I'm using ChaCha20-Poly1305 in a "full AEAD" mode, where a payload of data is encrypted and a block of unencrypted "additional data" is secured as well. However, I'd like to also occasionally use the ...
1
vote
1answer
77 views

Is a bit string pseudorandom if it starts with predictable bits?

Assume we have $k = n + m$ bits string $S$ where the first $n$ bits are predictable, and the last $m$ bits are pseudorandom (the HMAC of the first $n$ bits + IV). Can we say $S$ is a pseudorandom ...
2
votes
3answers
232 views

Is obfuscation considered a cryptographic primitive?

The general definition of obfuscation is the process of obscuring a message (not necessarily source code). There is a "rigorous" method for obfuscation (indistinguishability obfuscation, ...
2
votes
1answer
128 views

What is Regular Digest/Hash Function

I was reading a paper, Practical and Provably-Secure Commitment Schemes from Collision-Free Hashing where there was a reference to message digests being 'regular' Here, MD is a message digest. I've ...
5
votes
1answer
208 views

In cryptography, what is "fractionation"?

I understand how fractionation is used in the straddling keyboard, which is an important feature of the VIC Cipher, and in the Polybius Square of the ADFGVX cipher, but I am not sure how to describe ...
3
votes
3answers
372 views

Why is "key-rotation" called key-rotation?

The word "rotate" in respect to "key-rotation" has connotations of looping/repeating variable values like a rotor, but as far as I can tell there isn't a single definition available for "key-rotation" ...
6
votes
2answers
1k views

zk-SNARKs vs. Zk-STARKs vs. Bulletproofs: definitions

I have become quite familiar with Bulletproofs the last few months. Bulletproofs is the name given to a zero-knowledge proof system for arithmetic circuits, by Benedikt Bünz et al. It is a specific ...
1
vote
1answer
80 views

Definition of diffusion matrix

I've been studying this article and since I'm not studying cryptography in English and it is not my native language, I don't understand some of the terminology. More precisely: what are diffusion ...

1
2 3 4 5 6