Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Cryptography

Authenticated Key Exchange Protocol in the Standard Model under Weaker Assumptions

Janaka Alawatugoda

Published Jan 5, 2023• 2 citations
Publisher

Abstract

A two-party authenticated key exchange (AKE) protocol allows each of the two parties to share a common secret key over insecure channels, even in the presence of active adversaries who can actively control and modify the exchanged messages. To capture the malicious behaviors of the adversaries, there have been many efforts to define security models. Amongst them, the extended Canetti–Krawczyk (eCK) security model is considered one of the strongest security models and has been widely adopted. In this paper, we present a simple construction of a pairing-based eCK-secure AKE protocol in the standard model. Our protocol can be instantiated with a suitable signature scheme (i.e., an existentially unforgeable signature scheme against adaptive chosen message attacks). The underlying assumptions of our construction are the decisional bilinear Diffie–Hellman assumption and the existence of a pseudorandom function. Note that the previous eCK-secure protocol constructions either relied on random oracles for their security or used somewhat strong assumptions, such as the existence of strong-pseudorandom functions, target collision-resistant functions, etc., while our protocol construction uses fewer and more-standard assumptions in the standard model. Furthermore, preserving the same security argument, our protocol can be instantiated with any appropriate signature scheme that comes in the future with better efficiency.

DOI
10.3390/cryptography7010001

Related papers

Strongly Authenticated Key Exchange Protocol from Bilinear Groups without Random Oracles.

Zheng Yang, Jörg Schwenk

Malicious insider security of authenticated key exchange (AKE) protocol addresses the situation that an AKE protocol is secure even with existing dishonest parties established by adversary in corresponding security experiment. In the eCK model, the EstablishParty query is used to model the malicious insider setting. However such strong query is not clearly formalized so far. We show that the proof of possession assumptions for registering public keys are of prime importance to malicious insider security. In contrast to previous schemes, we present an eCK secure protocol in the standard model, without assuming impractical, strong, concurrent zero-knowledge proofs of knowledge of secret keys done to the CA at key registration. The security proof of our scheme is based on standard pairing assumption, collision resistant hash functions, bilinear decision Diffie-Hellman (BDDH) and decision linear Diffie-Hellman (DLIN) assumptions, and pseudo-random functions with pairwise independent random source πPRF [14].

•Jan 1, 2012•0 citations

An eCK-secure Authenticated Key Exchange Protocol Without Random Oracles

Daisuke Moriyama, Tatsuaki Okamoto

Two-party key exchange protocol is a mechanism in which two parties communicate with each other over an insecure channel and output the same session key.A key exchange protocol that is secure against an active adversary who can control and modify the exchanged messages is called authenticated key exchange (AKE) protocol.LaMacchia, Lauter and Mityagin presented a strong security definition for public key infrastructure (PKI) based two-pass protocol, which we call the extended Canetti-Krawczyk (eCK) security model, and some researchers have provided eCK-secure AKE protocols in recent years.However, almost all protocols are provably secure in the random oracle model or rely on a special implementation technique so-called the NAXOS trick.In this paper, we present a PKI-based two-pass AKE protocol that is secure in the eCK security model.The security of the proposed protocol is proven without random oracles (under three assumptions), and does not rely on implementation techniques such as the NAXOS trick.

KSII Transactions on Internet and Information Systems•Jan 1, 2011•11 citations

Efficient eCK-secure Authenticated Key Exchange Protocols in the Standard Model.

Zheng Yang

The extended Canetti–Krawczyk (eCK) security models, are widely used to provide security arguments for authenticated key exchange protocols that capture leakage of various kinds of secret information like the long-term private key and session-specific secret state. In this paper, we study the open problem on constructing eCK secure AKE protocol without random oracles and NAXOS like trick. A generic construction GC-KKN satisfying those requirements is first given relying on standard cryptographic primitives following the guideline of efficiency. On the second a concrete protocol is proposed which is the first eCK secure protocol in the standard model under both standard assumptions and post-specified peer setting. Both proposed schemes can be more efficiently implemented with secure device than previous eCK secure protocols in the standard model, where the secure device might be normally used to store the long-term private key and implement algorithms of protocol which require to be resilience of state leakage.

•Jan 1, 2013•0 citations

An ID-based authenticated key exchange protocol based on bilinear Diffie-Hellman problem

Hai Huang, Zhenfu Cao

In this paper, we present a new ID-based two-party authenticated key exchange (AKE) protocol, which makes use of a new technique called twin Diffie-Hellman problem proposed by Cash, Kiltz and Shoup. We show that our scheme is secure under bilinear Diffie-Hellman (BDH) assumption in the enhanced Canetti-Krawczyk (eCK) model, which better supports the adversary's queries than previous AKE models. To the best of our knowledge, our scheme is the first ID-based AKE protocol provably secure in eCK model.

ACM Asia Conference on Computer and Communications Security (ASIA CCS)•Mar 10, 2009•78 citations

A practical strongly secure one‐round authenticated key exchange protocol without random oracles

Zheng Yang, Yang Wu

Abstract Most recently, a variant of extended Canetti–Krawczyk model called aseCKwis introduced to provide stronger security than previous eCK models. NamelyeCKwmodels formulate a stronger notion regarding weak perfect forward secrecy than other eCK models. In particular, anyeCKwsecure protocols can be generally transformed to achieve full provide perfect forward secrecy without requiring additional round. So far, there is no protocol which has been proven secure in theeCKwmodel without random oracles. In this paper, we study the open problem on constructingeCKwsecure AKE protocol in the standard model. A new one‐round AKE protocol is introduced relying on standard cryptographic primitives and a variant of bilinear decisional Diffie–Hellman assumption. The main advantage of our proposal is its high efficiency in key exchange in contrast to the previous eCK secure protocols without random oracles and under post‐specified peer setting. Copyright © 2014 John Wiley & Sons, Ltd.

Security and Communication Networks•Sep 9, 2014•3 citations

Strongly Secure Authenticated Key Exchange in the Standard Model

Zheng Yang

Nowadays many crucial network applications rely on the existence of a confidential channel established by authenticated key exchange (AKE) protocols over public networks.With the rapid development of cyber technology, novel attacks to cryptosystem emerge in an endless stream.This has also led to the development of AKE solutions to provide increasingly stronger security guarantees.In this thesis we focus on provision of practical constructions for AKE protocols which are provably secure in a strong sense without resorting to random oracles.We first we present three new efficient compilers to generically turn passively secure key exchange protocols (KE) into authenticated key exchange protocols (AKE) where security also holds in the presence of active adversaries.Our compilers are not only a useful tool for the design of new AKE systems with many additional security properties in a modular and less error-prone fashion, but they also help to relax the assumptions on existing, practical key exchange mechanisms which are not known to be provably secure AKE protocols.Security of our compilers is shown in a strong modified CK model where the adversary is allowed to reveal either long-term secret key or state information of the protocol participants.On the second, we study the open problem on constructing eCK secure two party AKE protocol without random oracles and NAXOS trick.A generic construction satisfying those requirements is given based on well-known cryptographic primitives following the guideline of efficiency.Then a concrete protocol is proposed which is the first eCK secure protocol in the standard model under both standard assumptions and post-specified peer setting (i.e.without knowing any cryptographic information about its communication peer).Both proposed schemes can be more efficiently implemented with secure device than previous works which are eCK secure in the standard model, where the secure device might be normally used to store the long-term private key and to implement codes of protocol which need to be resilience of state leakage.Finally, we generalize our one-round two party AKE construction to group case that yields an efficient tripartite AKE protocol based on bilinear maps and a candidate group AKE protocol (with more than three members) based on multilinear maps.Up to now they are the first solutions which can be proved secure in the g-eCK model without random oracles.Meanwhile we make first step to show how to simplify the security proof for one-round group AKE under g-eCK model.i

•Jan 1, 2013•0 citations
A two-party authenticated key exchange (AKE) protocol allows each of the two parties to share a common secret key over insecure channels, even in the presence of active adversaries who can actively control and modify the exchanged messages. To capture the malicious behaviors of the adversaries, there have been many efforts to define security models. Amongst them, the extended Canetti–Krawczyk (eCK) security model is considered one of the strongest security models and has been widely adopted. In this paper, we present a simple construction of a pairing-based eCK-secure AKE protocol in the standard model. Our protocol can be instantiated with a suitable signature scheme (i.e., an existentially unforgeable signature scheme against adaptive chosen message attacks). The underlying assumptions of our construction are the decisional bilinear Diffie–Hellman assumption and the existence of a pseudorandom function. Note that the previous eCK-secure protocol constructions either relied on random oracles for their security or used somewhat strong assumptions, such as the existence of strong-pseudorandom functions, target collision-resistant functions, etc., while our protocol construction uses fewer and more-standard assumptions in the standard model. Furthermore, preserving the same security argument, our protocol can be instantiated with any appropriate signature scheme that comes in the future with better efficiency.
Malicious insider security of authenticated key exchange (AKE) protocol addresses the situation that an AKE protocol is secure even with existing dishonest parties established by adversary in corresponding security experiment. In the eCK model, the EstablishParty query is used to model the malicious insider setting. However such strong query is not clearly formalized so far. We show that the proof of possession assumptions for registering public keys are of prime importance to malicious insider security. In contrast to previous schemes, we present an eCK secure protocol in the standard model, without assuming impractical, strong, concurrent zero-knowledge proofs of knowledge of secret keys done to the CA at key registration. The security proof of our scheme is based on standard pairing assumption, collision resistant hash functions, bilinear decision Diffie-Hellman (BDDH) and decision linear Diffie-Hellman (DLIN) assumptions, and pseudo-random functions with pairwise independent random source πPRF [14].
Two-party key exchange protocol is a mechanism in which two parties communicate with each other over an insecure channel and output the same session key.A key exchange protocol that is secure against an active adversary who can control and modify the exchanged messages is called authenticated key exchange (AKE) protocol.LaMacchia, Lauter and Mityagin presented a strong security definition for public key infrastructure (PKI) based two-pass protocol, which we call the extended Canetti-Krawczyk (eCK) security model, and some researchers have provided eCK-secure AKE protocols in recent years.However, almost all protocols are provably secure in the random oracle model or rely on a special implementation technique so-called the NAXOS trick.In this paper, we present a PKI-based two-pass AKE protocol that is secure in the eCK security model.The security of the proposed protocol is proven without random oracles (under three assumptions), and does not rely on implementation techniques such as the NAXOS trick.
The extended Canetti–Krawczyk (eCK) security models, are widely used to provide security arguments for authenticated key exchange protocols that capture leakage of various kinds of secret information like the long-term private key and session-specific secret state. In this paper, we study the open problem on constructing eCK secure AKE protocol without random oracles and NAXOS like trick. A generic construction GC-KKN satisfying those requirements is first given relying on standard cryptographic primitives following the guideline of efficiency. On the second a concrete protocol is proposed which is the first eCK secure protocol in the standard model under both standard assumptions and post-specified peer setting. Both proposed schemes can be more efficiently implemented with secure device than previous eCK secure protocols in the standard model, where the secure device might be normally used to store the long-term private key and implement algorithms of protocol which require to be resilience of state leakage.
In this paper, we present a new ID-based two-party authenticated key exchange (AKE) protocol, which makes use of a new technique called twin Diffie-Hellman problem proposed by Cash, Kiltz and Shoup. We show that our scheme is secure under bilinear Diffie-Hellman (BDH) assumption in the enhanced Canetti-Krawczyk (eCK) model, which better supports the adversary's queries than previous AKE models. To the best of our knowledge, our scheme is the first ID-based AKE protocol provably secure in eCK model.
Abstract Most recently, a variant of extended Canetti–Krawczyk model called aseCKwis introduced to provide stronger security than previous eCK models. NamelyeCKwmodels formulate a stronger notion regarding weak perfect forward secrecy than other eCK models. In particular, anyeCKwsecure protocols can be generally transformed to achieve full provide perfect forward secrecy without requiring additional round. So far, there is no protocol which has been proven secure in theeCKwmodel without random oracles. In this paper, we study the open problem on constructingeCKwsecure AKE protocol in the standard model. A new one‐round AKE protocol is introduced relying on standard cryptographic primitives and a variant of bilinear decisional Diffie–Hellman assumption. The main advantage of our proposal is its high efficiency in key exchange in contrast to the previous eCK secure protocols without random oracles and under post‐specified peer setting. Copyright © 2014 John Wiley & Sons, Ltd.
Nowadays many crucial network applications rely on the existence of a confidential channel established by authenticated key exchange (AKE) protocols over public networks.With the rapid development of cyber technology, novel attacks to cryptosystem emerge in an endless stream.This has also led to the development of AKE solutions to provide increasingly stronger security guarantees.In this thesis we focus on provision of practical constructions for AKE protocols which are provably secure in a strong sense without resorting to random oracles.We first we present three new efficient compilers to generically turn passively secure key exchange protocols (KE) into authenticated key exchange protocols (AKE) where security also holds in the presence of active adversaries.Our compilers are not only a useful tool for the design of new AKE systems with many additional security properties in a modular and less error-prone fashion, but they also help to relax the assumptions on existing, practical key exchange mechanisms which are not known to be provably secure AKE protocols.Security of our compilers is shown in a strong modified CK model where the adversary is allowed to reveal either long-term secret key or state information of the protocol participants.On the second, we study the open problem on constructing eCK secure two party AKE protocol without random oracles and NAXOS trick.A generic construction satisfying those requirements is given based on well-known cryptographic primitives following the guideline of efficiency.Then a concrete protocol is proposed which is the first eCK secure protocol in the standard model under both standard assumptions and post-specified peer setting (i.e.without knowing any cryptographic information about its communication peer).Both proposed schemes can be more efficiently implemented with secure device than previous works which are eCK secure in the standard model, where the secure device might be normally used to store the long-term private key and to implement codes of protocol which need to be resilience of state leakage.Finally, we generalize our one-round two party AKE construction to group case that yields an efficient tripartite AKE protocol based on bilinear maps and a candidate group AKE protocol (with more than three members) based on multilinear maps.Up to now they are the first solutions which can be proved secure in the g-eCK model without random oracles.Meanwhile we make first step to show how to simplify the security proof for one-round group AKE under g-eCK model.i