FORMAL PROOF OF RELATIVE STRENGTH OF SECURITY AMONG ECK2007 MODEL AND OTHER PROOF MODELS FOR KEY AGREEMENT PROTOCOLS

The differences among the extended Canetti ＆ Krawezyk 2007 model （ECK2007） and other four models, i.e., the Bellare ＆ Rogaway （1993, 1995）models （BR93,BR95）, the Bellare, Pointcheval ＆ Rogaway （2000） model （BPR2000） and the Canetti ＆ Krawczyk （2001） model （CK2001） are given. The relative strength of security among these models is analyzed. To support the implication or non-implication relation among these models, the formal proof or the counter-example is provided.

A Resistant Quantum Key Exchange Protocol and Its Corresponding Encryption Scheme

The emergence of quantum computer will threaten the security of existing public-key cryptosystems, including the Diffie Hellman key exchange protocol, encryption scheme and etc, and it makes the study of resistant quantum cryptography very urgent. This motivate us to design a new key exchange protocol and eneryption scheme in this paper. Firstly, some acknowledged mathematical problems was introduced, such as ergodic matrix problem and tensor decomposition problem, the two problems have been proved to NPC hard. From the computational complexity prospective, NPC problems have been considered that there is no polynomial-time quantum algorithm to solve them. From the algebraic structures prospective, non-commutative cryptography has been considered to resist quantum. The matrix and tensor operator we adopted also satisfied with this non-commutative algebraic structures, so they can be used as candidate problems for resisting quantum from perspective of computational complexity theory and algebraic structures. Secondly, a new problem was constructed based on the introduced problems in this paper, then a key exchange protocol and a public key encryption scheme were proposed based on it. Finally the security analysis, efficiency, recommended parameters, performance evaluation and etc. were also been given. The two schemes has the following characteristics, provable security,security bits can be scalable, to achieve high efficiency, quantum resistance, and etc.

Efficient Authenticated Key Agreement Protocol Using Self-Certified Public Keys from Pairings

An efficient authenticated key agreement protocol is proposed, which makesuse of bilinear pairings and self-certificd public keys. Its security is based on the securityassumptions of the bilinear Diff ie-Hellman problem and the computational Diffie-Hellman problem.Users can choose their private keys independently. The public keys and identities of users can beverified implicitly when the session key being generating in a logically single step. A trusted KeyGeneration Center is no longer requiredas in the ID-based authenticated key agreement protocolsCompared with existing authenticated key agreement protocols from pairings, the. new proposedprotocol is more efficient and secure.

New semi-quantum key agreement protocol based on high-dimensional single-particle states

A new efficient two-party semi-quantum key agreement protocol is proposed with high-dimensional single-particle states.Different from the previous semi-quantum key agreement protocols based on the two-level quantum system,the propounded protocol makes use of the advantage of the high-dimensional quantum system,which possesses higher efficiency and better robustness against eavesdropping.Besides,the protocol allows the classical participant to encode the secret key with qudit shifting operations without involving any quantum measurement abilities.The designed semi-quantum key agreement protocol could resist both participant attacks and outsider attacks.Meanwhile,the conjoint analysis of security and efficiency provides an appropriate choice for reference on the dimension of single-particle states and the number of decoy states.

An Efficient Lightweight Authentication and Key Agreement Protocol for Patient Privacy

Tele-medical information system provides an efficient and convenient way to connect patients at home with medical personnel in clinical centers.In this system,service providers consider user authentication as a critical requirement.To address this crucial requirement,various types of validation and key agreement protocols have been employed.The main problem with the two-way authentication of patients and medical servers is not built with thorough and comprehensive analysis that makes the protocol design yet has flaws.This paper analyzes carefully all aspects of security requirements including the perfect forward secrecy in order to develop an efficient and robust lightweight authentication and key agreement protocol.The secureness of the proposed protocol undergoes an informal analysis,whose findings show that different security features are provided,including perfect forward secrecy and a resistance to DoS attacks.Furthermore,it is simulated and formally analyzed using Scyther tool.Simulation results indicate the protocol’s robustness,both in perfect forward security and against various attacks.In addition,the proposed protocol was compared with those of other related protocols in term of time complexity and communication cost.The time complexity of the proposed protocol only involves time of performing a hash function Th,i.e.,:O(12Th).Average time required for executing the authentication is 0.006 seconds;with number of bit exchange is 704,both values are the lowest among the other protocols.The results of the comparison point to a superior performance by the proposed protocol.

A secure key agreement protocol based on chaotic maps

To guarantee the security of communication in the public channel, many key agreement protocols have been proposed. Recently, Gong et al. proposed a key agreement protocol based on chaotic maps with password sharing. In this paper, Gong et al.＇s protocol is analyzed, and we find that this protocol exhibits key management issues and potential security problems. Furthermore, the paper presents a new key agreement protocol based on enhanced Chebyshev polynomials to overcome these problems. Through our analysis, our key agreement protocol not only provides mutual authentication and the ability to resist a variety of conarnon attacks, but also solve the problems of key management and security issues existing in Gong et al.＇ s protocol.

CLORKE-SFS:Certificateless One-Round Key Exchange Protocol with Strong Forward Security in Limited Communication Scenarios

Certificateless one-round key exchange(CL-ORKE)protocols enable each participant to share a common key with only one round of communication which greatly saves communication cost.CLORKE protocols can be applied to scenarios with limited communication,such as space communication.Although CL-ORKE protocols have been researched for years,lots of them only consider what secrets can be compromised but ignore the time when the secrets have been corrupted.In CL-ORKE protocols,the reveal of the long-term key attacks can be divided into two different attacks according to the time of the long-term key revealed:the attack to weak Forward Security(wFS)and the attack to strong Forward Security(sFS).Many CLKE protocols did not take into account the sFS property or considered sFS as wFS.In this paper,we first propose a new security model for CL-ORKE protocols which considers the sFS property as well as the Ephemeral Key Reveal attack.Then,we give a CL-ORKE protocol which is called CLORKE-SFS.CLORKE-SFS is provably secure under the proposed model provided the Elliptic Curve Computational Diffie-Hellman(ECCDH)and the Bilinear Computational Diffie-Hellman problem(BCDH)assumption hold.The security model and the protocol may give inspiration for constructing oneround key exchange protocols with perfect forward security in certificateless scenarios.

An efficient three-party password-based key agreement protocol using extended chaotic maps

Three-party password-based key agreement protocols allow two users to authenticate each other via a public channel and establish a session key with the aid of a trusted server. Recently, Farash et al. [Farash M S, Attari M A 2014 ＂An efficient and provably secure three-party password-based authenticated key exchange protocol based on Chebyshev chaotic maps＂, Nonlinear Dynamics 77（7）： 399-411] proposed a three-party key agreement protocol by using the extended chaotic maps. They claimed that their protocol could achieve strong security. In the present paper, we analyze Farash et al.＇s protocol and point out that this protocol is vulnerable to off-line password guessing attack and suffers communication burden. To handle the issue, we propose an efficient three-party password-based key agreement protocol using extended chaotic maps, which uses neither symmetric cryptosystems nor the server＇s public key. Compared with the relevant schemes, our protocol provides better performance in terms of computation and communication. Therefore, it is suitable for practical applications.

Twin-Field Quantum Key Distribution Protocol Based on Wavelength-Division-Multiplexing Technology

Quantum key distribution(QKD) generates information-theoretical secret keys between two parties based on the physical laws of quantum mechanics. Following the advancement in quantum communication networks, it becomes feasible and economical to combine QKD with classical optical communication through the same fiber using dense wavelength division multiplexing(DWDM) technology. This study proposes a detailed scheme of TF-QKD protocol with DWDM technology and analyzes its performance, considering the influence of quantum channel number and adjacent quantum crosstalk on the secret key rates. The simulation results show that the scheme further increases the secret key rate of TF-QKD and its variants. Therefore, this scheme provides a method for improving the secret key rate for practical quantum networks.

Universally Composable Symbolic Analysis of Group Key Exchange Protocol

Canetti and Herzog have already proposed universally composable symbolic analysis(UCSA) to analyze mutual authentication and key exchange protocols. However,they do not analyze group key exchange protocol. Therefore,this paper explores an approach to analyze group key exchange protocols,which realize automation and guarantee the soundness of cryptography. Considered that there exist many kinds of group key exchange protocols and the participants’ number of each protocol is arbitrary. So this paper takes the case of Burmester-Desmedt(BD) protocol with three participants against passive adversary(3-BD-Passive) . In a nutshell,our works lay the root for analyzing group key exchange protocols automatically without sacrificing soundness of cryptography.

Key Management Protocol of the IEEE 802.16e

IEEE 802.16e, as an amendment and corrigendum to the IEEE 802.16-2004, published on 28 February 2006, and intended to update and expand IEEE 802.16-2004 to allow for mobile subscriber stations. This paper summarizes the key management protocol belonging to security part of the IEEE 802.16e, which includes security negotiation, authorization, key derivation, handshake, and key transportation. While these building blocks are well designed, we point out some unwelcome features for these building blocks. We also give out suggestions to diminish the proposed problems.

A novel approach to authenticated group key transfer protocol based on AG codes

Group key management technique is a fundamental building block for secure and reliable group communication systems.In order to successfully achieve this goal, group session key needs to be generated and distributed to all group members in a secure and authenticated manner.The most commonly used method is based on Lagrange interpolating polynomial over the prime field F p={0,1,2,…, p-1}. A novel approach to group key transfer protocol based on a category of algebraic-geometry code is presented over the infinite field GF(2 m). The attractive advantages are obvious. Especially, the non-repeatability, confidentiality, and authentication of group key transfer protocols are obtained easily. Besides, a more generalized and simple mathematical construction model is proposed which also can be applied perfectly to related fields of information security.

Proof of Security of a Semi-Device-Independent Quantum Key Distribution Protocol

Semi-device-independent quantum key distribution （SDI-QKD） has been proposed by applying the quantum dimension correlation, and the security relies on the violation of quantum dimension witness inequalities. We prove the security of the SDI-QKD protocol under the depolarization channel by considering the quantum dimension witness inequalities and minimum entropy and the specific process of the QKD protocol, combining with a four- quantum-state preparation and three measurement bases. We also provide the relationship between the dimension witness value, the error rate and the security key rate by the numerical simulation.

Security Analysis of Broadcaster Group Key Exchange Protocols

Group key exchange protocols are basic protocols to provide privacy and integrity in secure group communication. This paper discusses the security of one type of group key exchange protocols and defines the kind of protocols as broadcaster group protocols. It points out two attacks on this kind of protocols. The first attack can be avoided by using fresh values in each action during one session of the group protocol. The second attack should be related with concrete application. It also proposes a dynamic key agreement protocol as an example of solutions at the last part of the paper.

STRONGER PROVABLE SECURE MODEL FOR KEY EXCHANGE

The key exchange is a fundamental building block in the cryptography. Several provable security models for the key exchange protocol are proposed. To determine the exact properties required by the protocols, a single unified security model is essential, The eCK , eCK and CK models are examined and the result is proved that the eCK＇ model is the strongest provable security model for the key exchange. The relative security strength among these models is analyzed. To support the implication or non-implication relations among these models, the formal proofs and the counter-examples are given.

Round-robin differential quadrature phase-shift quantum key distribution

Recently,a round-robin differential phase-shift（RRDPS） protocol was proposed[Nature 509,475（2014）],in which the amount of leakage is bounded without monitoring the signal disturbance.Introducing states of the phase-encoded Bennett-Brassard 1984 protocol（PE-BB84） to the RRDPS,this paper presents another quantum key distribution protocol called round-robin differential quadrature phase-shift（RRDQPS） quantum key distribution.Regarding a train of many pulses as a single packet,the sender modulates the phase of each pulse by one of {0,π/2,π,3π/2},then the receiver measures each packet with a Mach-Zehnder interferometer having a phase basis of 0 or π/2.The RRDQPS protocol can be implemented with essential similar hardware to the PE-BB84,so it has great compatibility with the current quantum system.Here we analyze the security of the RRDQPS protocol against the intercept-resend attack and the beam-splitting attack.Results show that the proposed protocol inherits the advantages arising from the simplicity of the RRDPS protocol and is more robust against these attacks than the original protocol.

Formal Verification in 3oux Tripartite Diffie-Hellman Protocol

Security analysis of cryptographic protocols has been widely studied for many years.As far as we know,we have not found any methods to effectively analyze group key exchange protocols for the three parties yet,which did not sacrifice the soundness of cryptography.Recently,Canetti and Herzog have proposed Universally Composable Symbolic Analysis(UCSA) of two-party mutual authentication and key exchange protocol which is based on the symmetric encryption schemes.This scheme can analyze the protocols automatically and guarantee the soundness of cryptography.Therefore,we discuss group key exchange protocol which is based on Joux Tripartite Diffie-Hellman(JTDH) using UCSA.Our contribution is analyzing group key exchange protocol effectively without damaging the soundness of cryptography.

New Public Key Cryptosystems from Combinatorial Group Theory

External direct product of some low layer groups such as braid groups and general Artin groups, with a kind of special group action on it, provides a secure cryptographic computation platform, which can keep secure in the quantum computing epoch. Three hard problems on this new platform, Subgroup Root Problem, Multi-variant Subgroup Root Problem and Subgroup Action Problem are presented and well analyzed, which all have no relations with conjugacy. New secure public key encryption system and key agreement protocol are designed based on these hard problems. The new cryptosystems can be implemented in a general group environment other than in braid or Artin groups.

An Efficient Two-Party Key Exchange Protocol with Strong Security

Combined public key （CPK） cryptography does not need certificates to guarantee the authenticity of public keys and avoids the inherent key escrow problem of identity-based cryptography. Based on the efficient CPK scheme, we present an efficient three-round two-party authenticated key exchange protocol with strong security, which is provably secure in the standard model under the decisional Diffie-Hellman （DDH） assumption. The protocol can keep the session key secret from the adversary except that one party＇s ephemeral private key and static private key are all revealed to the adversary. Compared to the existing protocols, this protocol not only assures strong security but also is more efficient.

An Improved ID-Based Group Key Agreement Protocol

ID-based constant-round group key agreement protocols are efficient in both computation and communication, but previous protocols did not provide valid message authentication. An improvement based on attack analysis is proposed in this paper. The improved method takes full advantage of the data transmitted at various stages of the protocol. By guaranteeing the freshness of authentication messages, the authenticity of the generator of authentication messages, and the completeness of the authenticator, the improved protocol can resist various passive and active attacks. The forward secrecy of the improved protocol is proved under a Katz-Yung （KY） model. Compared with existing methods, the improved protocol is more effective and applicable.