Skip to main content
New
Stack Overflow Jobs powered by Indeed: A job site that puts thousands of tech jobs at your fingertips (U.S. only). Search jobs

Questions tagged [abe]

Attribute-Based Encryption is 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 set of attributes of the user includes all the attributes used to encrypt the ciphertext.

Filter by
Sorted by
Tagged with
0 votes
0 answers
13 views

in MA-ABE, what is the diference when prove a scheme is selective or static?

I have read [1]Decentralized Multi-authority ABE for NC1 from BDH, [2]Decentralizing Attribute-Based Encryption, [3]Fully Adaptive Decentralized Multi-Authority ABE, When I compare security proof in [...
Wang Xingwang's user avatar
2 votes
0 answers
74 views

Why are most ABE KeyGen algorithms probabilistic algorithms?

It seems that in most Attribute Based Encryption schemes, the keygen algorithm is probabilistic, which means that given the same public key, master secret key and attribute set (or access structure), ...
CHG's user avatar
  • 31
0 votes
0 answers
27 views

Security proof of this paper(Ciphertext-Policy Attribute-Based Encryption) which proposes the first CP-ABE scheme

I have trouble in understanding the security proof of this paper(Ciphertext-Policy Attribute-Based Encryption) why are these two hybrids equivalent to the modified game above? It is obvious that $...
WF Huang's user avatar
2 votes
1 answer
50 views

Which one is more general, attribute based encryption or inner product predicate encryption?

If we have a scheme for inner product predicate encryption (IPPE), then can we claim that we already have designed an attribute based encryption (ABE) scheme; So we do not need to design an ABE again. ...
user1035648's user avatar
1 vote
1 answer
95 views

On the spectral norm in lattice-based cryptography

In the preliminaries section of a paper$^\color{magenta}{\star}$ on lattice-based cryptography, the matrix norm $\| \cdot \|_{2}$ is used. Why do we define such norm? What's the purpose of defining ...
user1035648's user avatar
3 votes
1 answer
119 views

Why do we need "selective security" for ABE?

The general question is: Why are ABE schemes usually/sometimes proven in the selective-set of attributes model of security? Or even co-selective (both attributes and policy function)? Is it just ...
user1035648's user avatar
2 votes
1 answer
113 views

Multi party authentication or encryption

I rent a room in a building. There are also 9 others who rent other rooms in this building. Just like everyone else who rents a room I only have one key of this building. With my key I can open the ...
Quinten C's user avatar
  • 123
0 votes
0 answers
27 views

reason of using $y=0$ result in ABE for arithmetic circuits

In Boneh et. al.'s ABE scheme (https://eprint.iacr.org/2013/669.pdf, https://link.springer.com/content/pdf/10.1007/978-3-642-55220-5_30.pdf), the result value for the arithmetic function is selected ...
Mahdi Mahdavi's user avatar
1 vote
1 answer
78 views

What is the meaning of the power notation in the access structure?

In the paper about ABE (like this), the access structure is defined as follow: Let ${P_1,P_2,...,P_n}$ be a set of parties. A collection $A⊆2^{\{P_1,P_2,...,P_n\}}$ is monotone if $∀B,C$: if $B∈A$ ...
Z. Chen's user avatar
  • 185
1 vote
1 answer
69 views

Combining CP-ABE and KP-ABE by wrapping one with the other?

I've looked around but can't find any discussion on using both CP-ABE and KP-ABE by simply wrapping one with the other. It seems like you'd be able to get more fine grained access control with a ...
Zachary Whitley's user avatar
2 votes
1 answer
122 views

KP-ABE Key Generation

In Key Policy Attribute-based encryption if we need a targeted broadcast where the set of attributes are the same for a group of users. It means they all share the same secret key right? Or is it that ...
Novice_researcher's user avatar
1 vote
1 answer
105 views

Adaptive Security Advantage

Adaptive model: the attacker can adaptively query the challenger for private keys. The challenge message need not be revealed at the start of the security game Selective model: the attacker has to ...
Novice_researcher's user avatar
1 vote
1 answer
83 views

Developments in ABE using Pairings

What are the recent developments in Attribute-Based Encryption (ABE) using Pairings assumptions? Is pairings the most viable assumption while designing ABE. What other assumptions are used for ABE ...
Novice_researcher's user avatar
1 vote
1 answer
175 views

What are access structures in Attribute-Based Encryption?

I'm reading this article, but I could'nt figure out Definition 1 (Access Structure) on page 3, section 3.1. It says: Let $\{P_1, P_2,...,P_n\}$ be a set of parties. A collection $\mathbb{A} \subseteq ...
user1108's user avatar
2 votes
2 answers
228 views

How to find the co-efficients of a function within Zp[x]?

I am a newbie in Finite Field arithmetic and while trying to implement an Elliptic Curve Cryptography based ABE scheme in a programming language, I am unable to understand how to implement function ...
RJ_SU's user avatar
  • 29
0 votes
0 answers
24 views

I wanted to know the size of plaintext, key and ciphertext of the KP-ABE algorithm

I have to present an ieee paper at my college, and I picked up a topic based on KP-ABE encryption and the paper doesn't have the size of plaintext, key and ciphertext in it
Prajoy's user avatar
  • 1
3 votes
1 answer
241 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} \...
Kluddizz's user avatar
  • 133
1 vote
1 answer
74 views

CP-ABE (Bethencourt): How KeyGen computes $D=g^{(\alpha+r)/\beta}$?

I have one doubt from CP-ABE KeyGen algorithm (paper). In Setup, master key is $MK=(\beta, g^\alpha)$. In KeyGen(MK, S), they say generate random number $r$ and compute $D=g^{(\alpha+r)/\beta}$. ...
user60588's user avatar
  • 287
1 vote
1 answer
102 views

What is the difference between $\in$ and $\in_{\small R}$?

I have a simple question about basic math. When I read different papers bout ABE, I see different methods to choose a random exponent. What is the difference between the following options? Choose a ...
tesoke's user avatar
  • 181
1 vote
1 answer
213 views

Is hybrid encryption required to use Attribute based Encryption to encrypt messages?

Does the mechanism behind Attribute Based Encryption require us to first encrypt the message by using a symmetric cipher, e.g. AES, and then encrypt the AES key by using Attribute Based Encryption? ...
user74341's user avatar
0 votes
0 answers
56 views

Is attribute-based encryption used to encrypt data and apply access control, or only do the latter?

I am trying to decide whether to encrypt data by using attribute-based encryption or use an encryption algorithm such as AES before using attribute-based encryption. Is attribute-based encryption ...
user74341's user avatar
3 votes
1 answer
431 views

Can anyone elaborate why KP-ABE is better than CP-ABE for television program broadcasting?

I know the difference between KP-ABE and CP-ABE. I am not able to understand why KP-ABE is better for broadcasting than CP-ABE ?
Richa's user avatar
  • 83
0 votes
0 answers
60 views

Proxy decrypt algorithm in Extended Proxy-Assisted Attribute Based Encryption (ABE) Scheme

Context I'm trying to implement the Attribute-Based Encryption (ABE) scheme described in the paper - Extended Proxy-Assisted Approach: Achieving Revocable Fine-Grained Encryption of Cloud Data (Yang ...
doughgle's user avatar
  • 103
3 votes
2 answers
124 views

Are attributes of an access structure visible or guessable in a CP-ABE ciphertext?

Suppose that Alice has attributes A, B and C. I have a ciphertext with this policy: A AND C. Can an adversary guess the attributes and then decrypt the ciphertext? What is the probability of ...
user65364's user avatar
2 votes
0 answers
85 views

Correctness Proof in "A tree-based CP-ABE scheme with hidden policy ... "

I could not understand one step in correctness proof of paper titled "A tree-based CP-ABE scheme with hidden policy supporting secure data sharing in cloud computing" authored by Runhua Xu, Yang Wang,...
user60588's user avatar
  • 287
2 votes
1 answer
116 views

DecryptNode for non-leaf Node in CP-ABE

I've looked at paper Ciphertext-Policy Attribute-Based Encryption by Bethencourt, Sahai, Waters and see this an answer here for the explanation of DecrypNode for a ...
user60588's user avatar
  • 287
2 votes
1 answer
446 views

What is the relationship between attribute based encryption (ABE) and access control?

So if possible could someone tell me or at least recommend a book.
user658961's user avatar
1 vote
1 answer
307 views

Adaptive vs. Static security model in ABE

From Lewko, I understand the difference between an adaptive and selective model: Adaptive model: the attacker can adaptively query the challenger for private keys. Selective model: the attacker has ...
Tri Vo Hoang's user avatar
4 votes
3 answers
170 views

Scheme that encrypt with $n$ pk that any sk of the pks can decrypt?

Suppose there are $n$ users each with public/private key pair $(pk_i,sk_i)$ $i=1,\cdots,n$. Is there any scheme that I can encrypt $m$ using the set of public keys $(pk_1,\cdots,pk_n)$, and can ...
Felix LL's user avatar
  • 321
1 vote
1 answer
847 views

derive child keys from a private key

My problem is the following: I have an organization with many members. When someone from the outside communicates with this organization, I want any member to be able to decrypt the communication. ...
bejito's user avatar
  • 11
2 votes
0 answers
174 views

Why only ABE is used in ABAC

Why ABAC access control model uses ABE not RSA or any other public key cryptography? Moreover what is the relation of ABAC with public key cryptography (ABE/RSA)?
Richa's user avatar
  • 83
1 vote
0 answers
50 views

What are general circuits exactly?

This may be a silly question but while reading this paper Circuit ABE from LWE, I came across this question on 2nd page - Is there an ABE scheme for general circuits with unbounded attribute length ...
chelsea's user avatar
  • 404
2 votes
2 answers
752 views

Access tree and Key geneation in KP-ABE

I tried for about 1 month to understand ABE and know I am confusing about access tree. In paper "Attributed-based encryption for fine-grained access control of encrypted data" the author explained the ...
tesoke's user avatar
  • 181
1 vote
2 answers
2k views

multiplication of two points belong to elliptic curve

I have a question about multiplication of two points belong to elliptic curve. I know every think about adding and scalar multiplication but not about multiplication of two points. Is there any method ...
tesoke's user avatar
  • 181
1 vote
1 answer
455 views

ABE (attribute based encryption) vs ABS (attribute based signature)

I want to know if there is any shortcoming that ABE cannot achieve and that the ABS complete it. I mean why the ABS is included if the authentication and the authorization are already ensured by the ...
A.Gh's user avatar
  • 19
2 votes
2 answers
3k views

I cannot understand the concept of a divisor for an elliptic curve

I am trying to understand ABE for a project of mine. I've grasped the concept of elliptic curves, but could not understand the meaning of divisors for functions on them. Could anyone help me with ...
tesoke's user avatar
  • 181
3 votes
1 answer
107 views

Enabling Oblivious Access Control via Function Encryption

Abstract With Functional Encryption, would access control between two parties be possible without revealing the entirety of one party's policy to the other? E.g. such that a server would be incapable ...
ruffsl's user avatar
  • 201
3 votes
2 answers
721 views

Attribute Authentication in Attribute Based Encryption (ABE)

When a data user requires access it asks the key issuer to generate a key for it using the specified attributes. How does the key issuer authenticate that the data user actually acquires the ...
user12's user avatar
  • 31
0 votes
1 answer
263 views

What cryptographic protocol or algorithm I can use to encrypt/decrypt a subset of columns of a database table for each user?

What cryptographic protocol or algorithm I can use to encrypt/decrypt a subset of columns of a database table for each user? For example say I have a database table with 50 columns ...
user1870400's user avatar
0 votes
3 answers
213 views

How to encrypt a message such when a certain condition is met it can be decrypted?

Assume, there is a certificate authority whose public key: $pk$, is known. Also, the certificate $c$ is known, but not the signed certificate. I want to encrypt a message: $m$, such that whoever has a ...
Aydin's user avatar
  • 442
0 votes
1 answer
215 views

About numberical comparison in Attribute based encryption

The first CP-ABE scheme in [BSW07] gave an example how to present a numberical comparison (e.g., a<11) to a Boolean access tree. But it seems like this feature is not implemented in Charm. In the ...
Tri Vo Hoang's user avatar
1 vote
0 answers
230 views

What is the key size and security level of attribute-based encryption schemes?

I am studying the ABE for my masters theses however I want to calculate the key and it's strength. I have done a research about the KP-ABE and I want to know the size of the key and how to determine ...
Mhamed Ali Kma's user avatar
1 vote
0 answers
121 views

Certificate Master Public Key with Pairing

I am currently working on CipherText Policy Attribute Based Encryption (CP-ABE) scheme. If we see the scheme, we can notice that the Authority may generate a Master Public Key and a Master Private Key(...
CipherX's user avatar
  • 381
11 votes
1 answer
286 views

Are pairings still the most efficient implementation for identity and attribute-based encryption?

I read on Wikipedia: [...] pairings have also been used to construct many cryptographic systems for which no other efficient implementation is known, such as identity based encryption or attribute ...
Shalec's user avatar
  • 407
-1 votes
1 answer
114 views

Will the ABE scheme based on RSA generate a constant secret key better than schemes based on elliptic curve cryptography?

We know in terms of security level, that an ECC key is stronger than an RSA one (e.g. a 160-bit ECC key would be equivalent to a 1024-bit key in RSA). If I can generate a constant secret key based on ...
MOBT's user avatar
  • 121
2 votes
0 answers
138 views

Why does the DBDH simulator have half the advantage of an adversary?

Literature that includes the DBDH assumption such as this paper or this paper has a formal security proof that states: Suppose an adversary with non-negligible advantage $\varepsilon = Adv$. A ...
user123's user avatar
  • 21
2 votes
0 answers
667 views

Which Attribute Based Encryption method is better for broadcast encryption? (KP-ABE or CP-ABE)

I have a basic understanding of public-private and symmetric crypto, but I keep struggling with the concept of ABE. I know the difference between the two variants: Key-Policy: A key is linked to a ...
user1226868's user avatar
1 vote
1 answer
378 views

How can I plot graphs of CP-ABE scheme using charm crypto?

Can I use charm crypto tool to run it over my datasets for CPABE scheme and plot graphs using its Benchmarking tool ? Or, how can I use Charm Crypto tool with CPABE toolkit ?
ut42's user avatar
  • 59
1 vote
0 answers
246 views

How are attributes encoded in private keys in Attribute-Based Encryption?

I understand how private keys are generated from public keys in a setup like Bitcoin (using ECDSA). I understand that anyone can verify they have the 'correct' private key using a digital signature ...
SingularityFuture's user avatar
2 votes
1 answer
148 views

What cipher(s) can or should I use for attribute based encryption?

What cipher(s) can or should I use for attribute based encryption? Can I use AES for that, or should I use some other, specific cipher(s)?
lochan's user avatar
  • 21