In identity-based encryption (IBE) the public key of a user $A$ is some identity string $ID_A$, e.g., an email address. To encrypt a message for this user there is no need to retrieve an authentic copy of the public key, as it is in public key cryptography, but one can simply use the identity string ...

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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 ...
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How to prove identity without revealing identity

Let us say Alice publishes a book under the name of Claire. The book becomes wildly popular and now Bob comes along, claiming to be Claire, to reap all the success. How does Alice prove that she wrote ...
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What is the “artificial abort” technique?

In the security proof of Brent Waters's paper Efficient Identity-Based Encryption Without Random Oracles, he uses a novel “artificial abort” step on page 6. At this point the simulator is still ...
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Question about dual system encryption

Recently, I have been reading some dual system encryption papers. In these systems, is the adversary able to generate “semi-functional ciphertexts”?
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Pairings in Identity-based encryption vs. Attribute-based encryption

The bilinear map in Identity-based encryption should satisfy $e(aP,bQ)=e(P,Q)^{a\cdot b}$ whereas Attribute-based encryption schemes use $e(P^a,Q^a)=e(P,Q)^{a\cdot b}$ with $a,b\in\mathbb{Z}_p$ and ...
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How to compare different signature scheme's performance?

I am interested in comparing the computational performance of two signature schemes. However, I am unsure how to do that. My candidates are RSA and Shamir's ID Based Signature scheme. To get a fair ...
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Shamir's ID based signatures - Notation issues

I am currently implementing Shamir's ID Based signature scheme as defined in the original paper. The sign and verify operation are defined as follows: Sign: $s = g * r^{f(t,m)} (\mod n)$ ...
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Shamir's ID based signatures

I am currently implementing Shamir's ID based signature algorithm as proposed in Adi Shamir, Identity-Based Cryptosystems and Signature Schemes. Advances in Cryptology: Proceedings of CRYPTO 84, ...
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what's the advantages of identity-based systems over certificate-based ones?

Actually, I'm not familiar to how identity-based and certificate-based systems work, so ,can anyone give me a detail and comprehensive answer to this question? Moreover, in what environments the ...
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Could MITM securely identify identity?

Consider protocol like QUIC or MinimaLT which are essentially layer4 replacement for TCP/UDP (riding on top of UDP currently because of fear of random firewalls dropping new L4 protocol). From crypto ...
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How does identification currently work with the German identity card? [closed]

Since 18th of December 2010 Germany makes use of an identity card that should allow electronic authentication: (image source: commons.wikipedia.org) From a users perspective, the authentication ...
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a possibly stronger type of attack on identity-based encryption

What is known about the security of identity-based encryption schemes against attacks that involve seeing multiple ciphertexts and then receiving the private keys corresponding to some of those ...
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What crypto system allows for 3 parties: Party 1 who makes an assertion, Party 2 mutates the assertion, Party 3 validates it

I'm looking for the cryptographic equivalent of a Drivers license where the issuer can be verified, the issuer doesn't need to know who you showed the drivers license to, but also allows ...
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Is there any semantic difference between predicate encryption and functional encryption?

Predicate encryption(PE) arrived as a descendant of attribute based encryption. Attribute based encryption allows the encryptor to embody a policy to the ciphertext (Ciphertext-Policy based ...