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Chosen-Ciphertext Secure Identity-Based Encryption in the Standard Model with short Ciphertexts.
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In this article, a practical identity-based encryption scheme that is secure in the standard model against chosen-ciphertext (IND-CCA2) attacks is described, which is based on an assumption similar to (but slightly stronger than) Bilinear Decisonal Di-e-Hellman (BDDH).Abstract:
We describe a practical identity-based encryption scheme that is secure in the standard model againstchosen-ciphertext(IND-CCA2)attacks. Securityisbasedonanassumptioncomparableto (but slightly stronger than) Bilinear Decisonal Di‐e-Hellman (BDDH). A comparison shows that our construction outperforms all known identity-based encryption schemes in the standard model anditsperformanceisevencomparablewiththeonefromtherandom-oraclebasedBoneh/Franklin IBEscheme. OurproposedIBEschemehasfurthermorethepropertythatitfulflllssomenotionof \redundancy-freeness",i.e. theencryptionalgorithmisnotonlyaprobabilisticinjectionbutalsoa surjection. As a consequence the ciphertext overhead is nearly optimal: to encrypt k bit messages for k bit identities and with k bit randomness we get 3k bit ciphertexts to guarantee (roughly) k bits of security.read more
Citations
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Book ChapterDOI
Chosen-Ciphertext Secure Proxy Re-encryption without Pairings
TL;DR: In this article, a new proxy re-encryption scheme without resorting to bilinear pairings is proposed, and the chosen-ciphertext security of the proposed scheme is proved in the random oracle model.
Book ChapterDOI
Efficient One-Round Key Exchange in the Standard Model
TL;DR: In this article, the authors consider one-round key exchange protocols secure in the standard model and show how KEMs can be used in a generic way to obtain two different protocol designs with progressively stronger security guarantees.
Book ChapterDOI
CCA2 secure IBE: standard model efficiency through authenticated symmetric encryption
Eike Kiltz,Yevgeniy Vahlis +1 more
TL;DR: In this article, the authors proposed two constructions of chosen-ciphertext secure identity-based encryption (IBE) schemes, which have a security proof in the standard model, yet they offer performance competitive with all known random-oracle based schemes.
Book ChapterDOI
Direct chosen-ciphertext secure identity-based key encapsulation without random oracles
Eike Kiltz,David Galindo +1 more
TL;DR: A new and practical identity-based key encapsulation mechanism that is secure in the standard model against choseniphertext (CCA2) attacks and more efficient than all previously proposed schemes.
Journal ArticleDOI
Provably Secure Timed-Release Public Key Encryption
TL;DR: This work formalizes the concept of a secure timed-release public-key cryptosystem and shows that, if a third party is relied upon to guarantee decryption after the specified date, this concept is equivalent to identity-based encryption; this explains the observation that all known constructions use identity- based encryption to achieve timed- release security.
References
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Book ChapterDOI
Identity-based cryptosystems and signature schemes
TL;DR: In this article, the authors introduce a novel type of cryptographic scheme, which enables any pair of users to communicate securely and to verify each other's signatures without exchanging private or public keys, without keeping key directories, and without using the services of a third party.
Proceedings ArticleDOI
Random oracles are practical: a paradigm for designing efficient protocols
Mihir Bellare,Phillip Rogaway +1 more
TL;DR: It is argued that the random oracles model—where all parties have access to a public random oracle—provides a bridge between cryptographic theory and cryptographic practice, and yields protocols much more efficient than standard ones while retaining many of the advantages of provable security.
Journal ArticleDOI
Identity-Based Encryption from the Weil Pairing
Dan Boneh,Matthew K. Franklin +1 more
TL;DR: This work proposes a fully functional identity-based encryption (IBE) scheme based on bilinear maps between groups and gives precise definitions for secure IBE schemes and gives several applications for such systems.
Book ChapterDOI
Efficient identity-based encryption without random oracles
TL;DR: This work first presents their IBE construction and reduces the security of the scheme to the decisional Bilinear Diffie-Hellman (BDH) problem, and shows that their techniques can be used to build a new signature scheme that is secure under the computational Diffie -Hellman assumption without random oracles.
Book ChapterDOI
A Practical Public Key Cryptosystem Provably Secure Against Adaptive Chosen Ciphertext Attack
Ronald Cramer,Victor Shoup +1 more
TL;DR: In this paper, a new public key cryptosystem is proposed and analyzed, which is provably secure against adaptive chosen ciphertext attack under standard intractability assumptions. But the scheme is quite practical, and is not provable to be used in practice.