An ECC‐based authenticated group key exchange protocol in IBE framework

With the rapid demand for various increasing applications, the internet users require a common secret key to communicate among a group. The traditional key exchange protocols involve a trusted key generation center for generation and distribution of the group key among the various group members. Therefore, the establishment of a trusted key generation center server and the generation (and distribution) of common session key require an extra overhead. To avoid this difficulty, a number of group key exchange protocols have been proposed in the literature. However, these protocols are vulnerable to many attacks and have a high computational and communication cost. In this paper, we present an elliptic curve cryptography–based authenticated group key exchange (ECC‐AGKE) protocol, which provides better security and has lower computational cost compared to related proposed schemes. Further, a complexity reduction method is deployed to reduce the overall complexity of the proposed elliptic curve cryptography–based authenticated group key exchange protocol. The security of proposed work is ensured by the properties of elliptic curves. A security adversarial model is given and an extensive formal security analysis against our claim is done in the random oracle model. We also made a comparison of our proposed protocol with similar works and found that ours have better complexity, security and efficiency over others.     

SRGH: A secure and robust group‐based handover AKA protocol for MTC in LTE‐A networks

Machine‐type communication (MTC) is defined as an automatic aggregation, processing, and exchange of information among intelligent devices without humans intervention. With the development of immense embedded devices, MTC is emerging as the leading communication technology for a wide range of applications and services in the Internet of Things (IoT). For achieving the reliability and to fulfill the security requirements of IoT‐based applications, researchers have proposed some group‐based handover authentication and key agreement (AKA) protocols for mass MTCDs in LTE‐A networks. However, the realization of secure handover authentication for the group of MTCDs in IoT enabled LTE‐A network is an imminent issue. Whenever mass MTCDs enter into the coverage area of target base‐station simultaneously, the protocols incur high signaling congestion. In addition, the existing group‐based handover protocols suffer from the huge network overhead and numerous identified problems such as lack of key forward/backward secrecy, privacy‐preservation. Moreover, the protocols fail to avoid the key escrow problem and vulnerable to malicious attacks. To overcome these issues, we propose a secure and robust group‐based handover (SRGH) AKA protocol for mass MTCDs in LTE‐A network. The protocol establishes the group key update mechanism with forward/backward secrecy. The formal security proof demonstrates that the protocol achieves all the security properties including session key secrecy and data integrity. Furthermore, the formal verification using the AVISPA tool shows the correctness and informal analysis discusses the resistance from various security problems. The performance evaluation illustrates that the proposed protocol obtains substantial efficiency compared with the existing group‐based handover AKA protocols.     

A fault‐tolerant group key agreement protocol exploiting dynamic setting

A fault‐tolerant group key agreement is an essential infrastructure for Internet communication among all involved participants; it can establish a secure session key no matter how many malicious participants exit simultaneously in an effort to disrupt the key agreement process. Recently, Zhao et al. proposed an efficient fault‐tolerant group key agreement protocol named efficient group key agreement that can resist denial‐of‐service attacks, reply attacks, man‐in‐middle attacks, and common modulus attacks; it can also preserve forward secrecy with lower computational cost than previous protocols. We show that it is still vulnerable to active attacks by malicious participants and modify the corresponding security weakness adaptively. Furthermore, we propose an efficient fault‐tolerant group key agreement based on a binary tree structure and enhance it to a dynamic setting where participants can leave or join the group arbitrarily according to their preferences with instant session key refreshment. Additionally, our session key refreshment is based on secure key updating to protect forward/backward confidentiality and is resistant to active/passive attacks. The performance analysis shows that our proposed protocol has lower computational cost and little additional communication cost exploiting dynamic setting. Copyright © 2013 John Wiley & Sons, Ltd.     

A secure and efficient password‐authenticated group key exchange protocol for mobile ad hoc networks

Password‐authenticated group key exchange protocols enable communication parties to establish a common secret key (a session key) by only using short secret passwords. Such protocols have been receiving significant attention. This paper shows some security weaknesses in some recently proposed password‐authenticated group key exchange protocols. Furthermore, a secure and efficient password‐authenticated group key exchange protocol in mobile ad hoc networks is proposed. It only requires constant round to generate a group session key under the dynamic scenario. In other words, the overhead of key generation is independent of the size of a total group. Further, the security properties of our protocol are formally validated by a model checking tool called AVISPA. Security and performance analyses show that, compared with other related group key exchange schemes, the proposed protocol is also efficient for real‐world applications in enhancing the security over wireless communications. Copyright © 2011 John Wiley & Sons, Ltd.     

A secure and robust group key distribution and authentication protocol with efficient rekey mechanism for dynamic access control in secure group communications

In today's Internet era, group communications have become more and more essential for many emerging applications. Given the openness of today's networks, efficient and secure distribution of common key is an essential issue for secure communications in the group. To maintain confidentiality during communication in the group, all authorized members require a common key called the group key in advance. This paper proposes a group key distribution and authentication protocol for dynamic access control in secure group communication using Chinese remainder theorem (CRT), which is highly secure and computationally efficient. The proposed protocol (1) has drastically reduced the computation complexity of group controller ( GC ) and members, (2) has provided intense security by means of an additional secret parameter used by GC and members, (3) has minimized storage and communication overheads, (4) has been decentralized for higher scalability so that it can efficiently handle large‐scale changes in the group membership, and (5) is suitable for many practical applications due to intense security along with low computation and storage overheads. Detailed security analysis proves that our protocol can guarantee the privacy and security requirements of group communications. Moreover, performance analysis also verifies the efficiency and effectiveness of the proposed protocol. The proposed protocol has been experimented on star topology‐based key distribution system and observed that the protocol significantly reduces the computation cost and minimizes the communication and storage overheads.     

An enhanced anonymous and unlinkable user authentication and key agreement protocol for TMIS by utilization of ECC

The telecare medicine information systems (TMISs) not only help patients to receive incessant health care services but also assist the medical staffs to access patients' electronic health records anytime and from anywhere via Internet. Since the online communications are exposed to numerous security threats, the mutual authentication and key agreement between patients and the medical servers are of prime significance. During the recent years, various user authentication schemes have been suggested for the TMISs. Nonetheless, most of them are susceptible to some known attacks or have high computational cost. Newly, an effective remote user authentication and session key agreement protocol has been introduced by Ravanbakhsh and Nazari for health care systems. Besides the nice contributions of their work, we found that it has two security weaknesses, namely, known session‐specific temporary information attack and lack of perfect forward secrecy. As a result, to overcome these deficiencies, this paper suggests a novel anonymous and unlinkable user authentication and key agreement scheme for TMISs using the elliptic curve cryptosystem (ECC). We have evaluated the security of the proposed scheme by applying the automated validation of internet security protocols and applications (AVISPA) tool with the intention of indicating that our scheme can satisfy the vital security features. In addition, we have compared the proposed protocol with related schemes to show that it has a proper level of performance. The obtained results demonstrate that the new scheme is more preferable considering both efficiency and security criteria.     

Strongly secure ID‐based authenticated key agreement protocol for mobile multi‐server environments

To provide mutual authentication and communication confidentiality between mobile clients and servers, numerous identity‐based authenticated key agreement (ID‐AKA) protocols were proposed to authenticate each other while constructing a common session key. In most of the existing ID‐AKA protocols, ephemeral secrets (random values) are involved in the computations of the common session key between mobile client and server. Thus, these ID‐AKA protocols might become vulnerable because of the ephemeral‐secret‐leakage (ESL) attacks in the sense that if the involved ephemeral secrets are compromised, an adversary could compute session keys and reveal the private keys of participants in an AKA protocol. Very recently, 2 ID‐AKA protocols were proposed to withstand the ESL attacks. One of them is suitable for single server environment and requires no pairing operations on the mobile client side. The other one fits multi‐server environments, but requires 2 expensive pairing operations. In this article, we present a strongly secure ID‐AKA protocol resisting ESL attacks under mobile multi‐server environments. By performance analysis and comparisons, we demonstrate that our protocol requires the lowest communication overhead, does not require any pairing operations, and is well suitable for mobile devices with limited computing capability. For security analysis, our protocol is provably secure under the computational Diffie‐Hellman assumption in the random oracle model.     

UCAP:a PCL secure user authentication protocol in cloud computing

As the combine of cloud computing and Internet breeds many flexible IT services,cloud computing becomes more and more significant.In cloud computing,a user should be authenticated by a trusted third party or a certification authority before using cloud applications and services.Based on this,a protocol composition logic (PCL) secure user authentication protocol named UCAP for cloud computing was proposed.The protocol used a symmetric encryption symmetric encryption based on a trusted third party to achieve the authentication and confidentiality of the protocol session,which comprised the initial authentication phase and the re-authentication phase.In the initial authentication phase,the trusted third party generated a root communication session key.In the re-authentication phase,communication users negotiated a sub session key without the trusted third party.To verify the security properties of the protocol,a sequential compositional proof method was used under the protocol composition logic model.Compared with certain related works,the proposed protocol satisfies the PCL security.The performance of the initial authentication phase in the proposed scheme is slightly better than that of the existing schemes,while the performance of the re-authentication phase is better than that of other protocols due to the absence of the trusted third party.Through the analysis results,the proposed protocol is suitable for the mutual authentication in cloud computing.     

An efficient certificateless key exchange protocol for heterogeneous networks in human-centered IoT systems

Human-centered Internet of things (IoT) systems enable human beings to enjoy the ubiquitous services and play more and more important roles in our life. A common application scenario in human-centered IoT systems is that two distributed wireless devices from heterogeneous networks want to communicate with each other. However, key generation centers (KGCs) from different networks usually use independent security parameters. It is difficult for two users with different security parameters to establish a common session key. We propose a certificateless key exchange protocol for two different devices managed by different KGCs to address the issue. The security of the proposed protocol is conducted in the random oracle model with the hardness assumption of elliptic curve computational Diffie-Hellman (ECDH) problem. The main merits of our protocol include the following: (a) it enables users from heterogeneous networks to establish upon a shared session key, (b) it can solve the key escrow problem, (c) it does not use bilinear pairings and obtains computational efficiency, and (d) it achieves stronger security compared with other related protocols.     

Secure group communication in wireless mesh networks

Wireless mesh networks (WMNs) have emerged as a promising technology that offers low-cost community wireless services. The community-oriented nature of WMNs facilitates group applications, such as webcast, distance learning, online gaming, video conferencing, and multimedia broadcasting. Security is critical for the deployment of these services. Previous work focused primarily on MAC and routing protocol security, while application-level security has received relatively little attention. In this paper we focus on providing data confidentiality for group communication in WMNs. Compared to other network environments, WMNs present new challenges and opportunities in designing such protocols. We propose a new protocol framework, Secure Group Overlay Multicast (SeGrOM), that employs decentralized group membership, promotes localized communication, and leverages the wireless broadcast nature to achieve efficient and secure group communication. We analyze the performance and discuss the security properties of our protocols. We demonstrate through simulations that our protocols provide good performance and incur a significantly smaller overhead than a baseline centralized protocol optimized for WMNs.     

结合双线性对和DLP的无证书两方认证协议

为解决无线通信网络中不同用户之间的通信安全问题,通常会采用身份认证协议来确保通信双方身份的合法性。该认证协议应能抵抗重放攻击、延时攻击等威胁,同时认证过程中的计算量应尽量小。本文针对SEAHA (secure and efficient handover authentication)认证方案存在的计算量大、不能抵抗伪装攻击的问题提出了一种基于双线性对和离散对数难题（DLP）的无证书两方认证协议。该协议中基站和节点共同生成节点密钥对来抵抗伪装攻击,利用离散对数难题生成会话密钥降低认证过程中的计算量。安全分析和性能分析结果表明,提出协议在保证安全性的前提下,有效降低了认证过程计算量。      

An efficient pairing‐free identity‐based authenticated group key agreement protocol

An authenticated group key agreement protocol allows participants to agree on a group key that will be subsequently used to provide secure group communication over an insecure network. In this paper, we give a security analysis on a pairing‐free identity‐based authenticated group key agreement because of Islam et al. We show that the protocol of Islam et al. cannot satisfy the minimal security requirements of the key agreement protocols. We propose an efficient pairing‐free identity‐based authenticated group key agreement for imbalanced mobile network. The proposed protocol can be implemented easily for practical application in mobile networks as it is free from bilinear. Under the difficulty of the InvCDH and CDH we demonstrate that the proposed protocol provides perfect forward secrecy, implicit key authentication and the dynamic functionality. As compared with the group key agreement protocols for imbalanced mobile network, the proposed protocol provides stronger security properties and high efficiency. Copyright © 2013 John Wiley & Sons, Ltd.     

基于椭圆曲线的隐私增强认证密钥协商协议

认证密钥协商协议能够为不安全网络中的通信双方提供安全的会话密钥,但是,大多数的认证密钥协商协议并没有考虑保护用户隐私.论文关注网络服务中用户的隐私属性,特别是匿名性和可否认性,规范了增强用户隐私的认证密钥协商协议应满足的安全需求,即双向认证、密钥控制、密钥确认、会话密钥保密、已知会话密钥安全、会话密钥前向安全、用户身份匿名、用户身份前向匿名、不可关联和可否认,并基于椭圆曲线密码系统设计了一个满足安全需求的隐私增强认证密钥协商协议.     

一个高效的基于身份的群密钥协商协议

群密钥协商协议是在Ad Hoc网络群通信中建立会话密钥的一种有效解决方法.但由于Ad Hoc网络是一个拓扑结构变化频繁的网络,因而在群通信中,不仅要建立一致的会话密钥,还要考虑成员变化的情况.文中结合完全二又树结构,提出了一种新的基于身份的群密钥协商协议.新方案具有隐含密钥认证、已知会话密钥安全,前向安全、抗密钥泄露攻击.抗未知密钥共享攻击、密钥控制等安全特性,并且效率较高.     

认证密钥协商协议

Key agreement and identification protocols are much applicable among current protocols in cryptography. These protocols are used for a secure communication through an insecure channel in a network like Internet. Challenge-response identification protocol is an important identification method. In this paper, by making some slight changes in the public-key-based challenge-response identification protocol, we have introduced a new scheme in which the users in addition to authenticating each other can also agree on multiple keys. Then, this protocol'es security from both aspects regarding the identification and key agreement will be analyzed. At the end, we will prove our scheme has a high security and efficiency in comparison with some famous and similar protocols.     

A chaotic map‐based anonymous multi‐server authenticated key agreement protocol using smart card

Authenticated key agreement protocols play an important role for network‐connected servers to authenticate remote users in Internet environment. In recent years, several authenticated key agreement protocols for single‐server environment have been developed based on chaotic maps. In modern societies, people usually have to access multiple websites or enterprise servers to accomplish their daily personal matters or duties on work; therefore, how to increase user's convenience by offering multi‐server authentication protocol becomes a practical research topic. In this study, a novel chaotic map‐based anonymous multi‐server authenticated key agreement protocol using smart card is proposed. In this protocol, a legal user can access multiple servers using only a single secret key obtained from a trusted third party, known as the registration center. Security analysis shows this protocol is secure against well‐known attacks. In addition, protocol efficiency analysis is conducted by comparing the proposed protocol with two recently proposed schemes in terms of computational cost during one authentication session. We have shown that the proposed protocol is twice faster than the one proposed by Khan and He while preserving the same security properties as their protocol has. Copyright © 2014 John Wiley & Sons, Ltd.     

一个可证安全的基于身份多密钥认证协商协议

An authentication multiple key agreement protocol allows the users to compute more than one session keys in an authentication way. In the paper, an identity-based authentication multiple key agreement protocol is proposed. Its authentication part is proven secure against existential forgery on adaptively chosen message and ID attacks under the random oracle model upon the CDH assumptions. The session keys are proven secure in a formal CK security model under the random oracle model upon the CBDH assumptions. Compared with the previous multiple key agreement protocols, it requires less communication cost.     

A new authenticated group key agreement in a mobile environment

A group key agreement protocol enables a group of communicating parties over an untrusted, open network to come up with a common secret key. It is designed to achieve secure group communication, which is an important research issue for mobile communication. In 2007, Tseng proposed a new group key agreement protocol to achieve secure group communication for a mobile environment. Its security is based on the decisional Diffie–Hellman assumption. It remedies the security weakness of the protocol of Nam et al. in which participants cannot confirm that their contributions were actually involved in the group key. Unfortunately, Tseng’s protocol is a nonauthenticated protocol that cannot ensure the validity of the transmitted messages. In this paper, the authors shall propose a new authenticated group key agreement to remedy it. It is based on bilinear pairings. We shall prove the security of the proposed protocol under the bilinear computational Diffie–Hellman assumption. It is also proven to a contributory group key agreement protocol.     

An off-line dictionary attack on a simple three-party key exchange protocol

Key exchange protocols allow two or more parties communicating over a public network to establish a common secret key called a session key. Due to their significance in building a secure communication channel, a number of key exchange protocols have been suggested over the years for a variety of settings. Among these is the so-called S-3PAKE protocol proposed by Lu and Cao for password-authenticated key exchange in the three-party setting. In the current work, we are concerned with the password security of the S-3PAKE protocol. We first show that S-3PAKE is vulnerable to an off-line dictionary attack in which an attacker exhaustively enumerates all possible passwords in an off-line manner to determine the correct one. We then figure out how to eliminate the security vulnerability of S-3PAKE.