A pairing‐free identity‐based handover AKE protocol with anonymity in the heterogeneous wireless networks

Nowadays, seamless roaming service in heterogeneous wireless networks attracts more and more attention. When a mobile user roams into a foreign domain, the process of secure handover authentication and key exchange (AKE) plays an important role to verify the authenticity and establish a secure communication between the user and the access point. Meanwhile, to prevent the user's current location and moving history information from being tracked, privacy preservation should be also considered. However, existing handover AKE schemes have more or less defects in security aspects or efficiency. In this paper, a secure pairing‐free identity‐based handover AKE protocol with privacy preservation is proposed. In our scheme, users' temporary identities will be used to conceal their real identities during the handover process, and the foreign server can verify the legitimacy of the user with the home server's assistance. Besides, to resist ephemeral private key leakage attack, the session key is generated from the static private keys and the ephemeral private keys together. Security analysis shows that our protocol is provably secure in extended Canetti‐Krawczyk (eCK) model under the computational Diffie‐Hellman (CDH) assumption and can capture desirable security properties including key‐compromise impersonation resistance, ephemeral secrets reveal resistance, strong anonymity, etc. Furthermore, the efficiency of our identity‐based protocol is improved by removing pairings, which not only simplifies the complex management of public key infrastructure (PKI) but also reduces the computation overhead of ID‐based cryptosystem with pairings. It is shown that our proposed handover AKE protocol provides better security assurance and higher computational efficiency for roaming authentication in heterogeneous wireless networks.     

An independent three‐factor mutual authentication and key agreement scheme with privacy preserving for multiserver environment and a survey

In the past decades, the demand for remote mutual authentication and key agreement (MAKA) scheme with privacy preserving grows rapidly with the rise of the right to privacy and the development of wireless networks and Internet of Things (IoT). Numerous remote MAKA schemes are proposed for various purposes, and they have different properties. In this paper, we survey 49 three‐factor–based remote MAKA schemes with privacy preserving from 2013 to 2019. None of them can simultaneously achieve security, suitability for multiserver environments, user anonymity, user untraceability, table free, public key management free, and independent authentication. Therefore, we propose an efficient three‐factor MAKA scheme, which achieves all the properties. We propose a security model of a three‐factor–based MAKA scheme with user anonymity for multiserver environments and formally prove that our scheme is secure under the elliptic curve computational Diffie‐Hellman problem assumption, decisional bilinear Diffie‐Hellman problem assumption, and hash function assumption. We compare the proposed scheme to relevant schemes to show our contribution and also show that our scheme is sufficiently efficient for low‐power portable mobile devices.     

X‐Region: A framework for location privacy preservation in mobile peer‐to‐peer networks

While enjoying various LBS (location‐based services), users also face the threats of location privacy disclosure. This is because even if the communications between users and LBS providers can be encrypted and anonymized, the sensitive information inside LBS queries may disclose the exact location or even the identity of a user. The existing research on location privacy preservation in mobile peer‐to‐peer (P2P) networks assumed that users trust each other and directly share location information with each other. Nonetheless, this assumption is not practical for most of the mobile P2P scenarios, for example, an adversary can pretend to be a normal user and collect the locations of other users. Aiming at this issue, this paper presents x‐region as a solution to preserve the location privacy in a mobile P2P environment where no trust relationships are assumed amongst mobile users. The main idea is to allow users to share a blurred region known as x‐region instead of their exact locations so that one cannot distinguish any user from others inside the region. We propose a theoretical metric for measuring the anonymity property of x‐region, together with three algorithms for generating an x‐region, namely, benchmark algorithm, weighted expanding algorithm, and aggressive weighted expanding algorithm. These algorithms achieve the anonymity and QoS requirements with different strategies. Our experiments verify the performance of the algorithms against three key metrics. Copyright © 2013 John Wiley & Sons, Ltd.     

Provable analysis and improvement of smart card–based anonymous authentication protocols

Nowadays, authentication protocols are essential for secure communications specially for roaming networks, distributed computer networks, and remote wireless communication. The numerous users in these networks rise vulnerabilities. Thus, privacy‐preserving methods have to be run to provide more reliable services and sustain privacy. Anonymous authentication is a method to remotely authenticate users with no revelation about their identity. In this paper, we analyze 2 smart card–based protocols that the user's identity is anonymous. However, we represent that they are vulnerable to privileged insider attack. It means that the servers can compromise the users' identity for breaking their privacy. Also, we highlight that the Wen et al protocol has flaws in both stolen smart card and stolen server attacks and the Odelu et al protocol is traceable. Then, we propose 2 modified anonymous authentication protocols. Finally, we analyze our improved protocols with both heuristic and formal methods.     

An anonymous biometric‐based remote user‐authenticated key agreement scheme for multimedia systems

We analyze the security of the Li et al . authentication scheme and show its vulnerability to off‐line password‐guessing and replay attacks. We design a new anonymous authentication scheme. The proposed scheme not only removes the drawback of the scheme of the Li et al . scheme but also protects user's anonymity. Moreover, we show validity of our proposed scheme using Burrows, Abadi, and Needham logic. Our scheme is comparable in terms of the communication and computational overhead with related schemes. Copyright © 2015 John Wiley & Sons, Ltd.     

A practical authentication protocol with anonymity for wireless access networks

The use of anonymous channel tickets was proposed for authentication in wireless environments to provide user anonymity and to probably reduce the overhead of re‐authentications. Recently, Yang et al. proposed a secure and efficient authentication protocol for anonymous channel in wireless systems without employing asymmetric cryptosystems. In this paper, we will show that Yang et al.'s scheme is vulnerable to guessing attacks performed by malicious visited networks, which can easily obtain the secret keys of the users. We propose a new practical authentication scheme not only reserving the merits of Yang et al.'s scheme, but also extending some additional merits including: no verification table in the home network, free of time synchronization between mobile stations and visited networks, and without obsolete anonymous tickets left in visited networks. The proposed scheme is developed based on a secure one‐way hash function and simple operations, a feature which is extremely fit for mobile devices. We provide the soundness of the authentication protocol by using VO logic. Copyright © 2010 John Wiley & Sons, Ltd.     

Anonymous and expeditious mobile user authentication scheme for GLOMONET environments

The Global Mobility Network (GLOMONET) is rapidly becoming important as well as a popular feature in today's high‐performance network. The legal mobile users enjoy life using the ubiquitous services via GLOMONET. However, because of the broadcast nature of the wireless channel, providing user authentication along with the privacy and anonymity of the users in GLOMONET is indeed a challenging task. In this article, we come up with a secure and expeditious mobile communication environment using symmetric key cryptosystem to ensure mobile users' anonymity and privacy against eavesdroppers and backward/forward secrecy of the session key. Our scheme can also protect numerous security threats, like man‐in‐the‐middle attack, known session key attack, lost smartcard attack, and forgery attack. Furthermore, we put forward a new technique named as “friendly foreign agent policy,” where many foreign agents can make different groups among themselves and perform important responsibilities to authenticate a legitimate mobile user without interfering his or her home agent even though the mobile user moves to a new location, covered by a new foreign agent (belongs to the same group). Security and performance analyses show that the proposed scheme is secure and more efficient as compared with other competitive schemes for GLOMONET environments.     

Cryptanalysis and improvement of ‘a robust smart‐card‐based remote user password authentication scheme’

With the use of smart card in user authentication mechanisms, the concept of two‐factor authentication came into existence. This was a forward move towards more secure and reliable user authentication systems. It elevated the security level by requiring a user to possess something in addition to know something. In 2010, Sood et al. and Song independently examined a smart‐card‐based authentication scheme proposed by Xu et al. They showed that in the scheme of Xu et al., an internal user of the system can turn hostile to impersonate other users of the system. Both of them also proposed schemes to improve the scheme of Xu et al. Recently, Chen et al. identified some security problems in the improved schemes proposed by Sood et al. and Song. To fix these problems, Chen et al. presented another scheme, which they claimed to provide mutual authentication and withstand lost smart card attack. Undoubtedly, in their scheme, a user can also verify the legitimacy of server, but we find that the scheme fails to resist impersonation attacks and privileged insider attack. We also show that the scheme does not provide important features such as user anonymity, confidentiality to air messages, and revocation of lost/stolen smart card. Besides, the scheme defies the very purpose of two‐factor security. Furthermore, an attacker can guess a user's password from his or her lost/stolen smart card. To meet these challenges, we propose a user authentication method with user anonymity. We show through analysis and comparison that the proposed scheme exhibits enhanced efficiency in contrast to related schemes, including the scheme of Chen et al. Copyright © 2013 John Wiley & Sons, Ltd.     

Privacy‐preserving multireceiver ID‐based encryption with provable security

Multireceiver identity (ID) based encryption and ID‐based broadcast encryption allow a sender to use the public identities of multiple receivers to encrypt messages so that only the selected receivers or a privileged set of users can decrypt the messages. It can be used for many practical applications such as digital content distribution, pay‐per‐view and multicast communication. For protecting the privacy of receivers or providing receiver anonymity, several privacy‐preserving (or anonymous) multireceiver ID‐based encryption and ID‐based broadcast encryption schemes were recently proposed, in which receiver anonymity means that nobody (including any selected receiver), except the sender, knows who the other selected receivers are. However, security incompleteness or flaws were found in these schemes. In this paper, we propose a new privacy‐preserving multireceiver ID‐based encryption scheme with provable security. We formally prove that the proposed scheme is semantically secure for confidentiality and receiver anonymity. Compared with the previously proposed anonymous multireceiver ID‐based encryption and ID‐based broadcast encryption schemes, the proposed scheme has better performance and robust security. Copyright © 2012 John Wiley & Sons, Ltd.     

An improved anonymous multi‐receiver identity‐based encryption scheme

Anonymous receiver encryption is an important cryptographic primitive. It allows a sender to use the public identities of multiple receivers to encrypt messages so that only the authorized receivers or a privileged set of users can decrypt the messages, and the identities of the receivers are not revealed. Recently, Zhang et al. proposed a novel anonymous multi‐receiver encryption scheme and claimed that their scheme could realize the receiver's identity privacy. Unfortunately, in this paper, we pointed out that the scheme by Zhang et al. did not achieve the anonymity of the receiver identity after analyzing the security of the scheme. At the same time, we give the corresponding attack. After analyzing the reason to produce such attacks, a novel anonymous multi‐receiver encryption scheme is given to achieve the anonymity of the receiver's identities. And we formally prove that the proposed scheme is semantically secure for confidentiality and receiver identities’ anonymity. The security of the scheme is based on decisional bilinear Diffie‐Hellman problem. Compared with the scheme by Zhang et al., Fan et al., Wang et al., and Chien et al., our scheme is shown to be better performance and robust security. To the best of our knowledge, our scheme is most efficient in terms of computational cost and communication overhead. Copyright © 2013 John Wiley & Sons, Ltd.     

A hidden mutual authentication protocol for low‐cost RFID tags

Radio‐frequency identification (RFID) technology enables the identification and tracking of objects by means of the wireless signals emitted by a tag attached to the objects of interest. Without adequate protection, however, malicious attackers can easily eavesdrop, scan or forge the information within the tag, thereby threatening the integrity of the system. Previous research has shown that the basic security requirements of RFID systems, i.e. identity authentication, information privacy and location privacy, can be satisfied using conventional cryptographic components. However, such components are expensive, and therefore conflict with the general requirement for low‐cost tag designs. Accordingly, this paper presents a low‐cost challenge‐response security protocol designated as the hidden mutual authentication protocol (HMAP) to accomplish both a mutual authentication capability between the tag and the reader and information privacy. The results show that HMAP provides an efficient means of concealing the authentication messages exchanged between the tag and the reader and is robust toward replay attacks. In addition, it is shown that HMAP is easily extended to provide complete location privacy by utilizing a hash function to generate different tag identifiers in each authentication session. Copyright © 2011 John Wiley & Sons, Ltd.     

Using group anonymity to hide the identity of VoIP mobile users communicating over hybrid networks while preserving quality of service

Security and privacy have become critical in computer networks, especially with the emergence of E‐commerce. Other than securing the transfer of data, users are interested in protecting their profile privacy against exposure attacks. Multimedia communications are at the core of new information and communication technologies. We seek to achieve end users' profile privacy without violating the Quality of Service constraints on the throughput, end‐to‐end delay, and jitter, as these parameters represent the critical factors in multimedia applications. We propose an end‐to‐end anonymity design that takes into consideration the constraints of Voice‐over‐IP applications in a hybrid network environment, which involves ad hoc and infrastructure networks. Using clusterheads for communication anonymity to preserve user profile privacy, as well as encryption of the real‐time protocol payload, we prove using analysis and simulations that our model can be easily integrated into currently deployed network infrastructures. Copyright © 2016 John Wiley & Sons, Ltd.     

Privacy-enhanced,Attack-resilient Access Control in Pervasive Computing Environments with Optional Context Authentication Capability

In pervasive computing environments (PCEs), privacy and security are two important but contradictory objectives. Users enjoy services provided in PCEs only after their privacy issues being sufficiently addressed. That is, users could not be tracked down for wherever they are and whatever they are doing. However, service providers always want to authenticate the users and make sure they are accessing only authorized services in a legitimate way. In PCEs, such user authentication may include context authentication in addition to the entity authentication. In this paper, we propose a novel privacy enhanced anonymous authentication and access control scheme to secure the interactions between mobile users and services in PCEs with optional context authentication capability. The proposed scheme seamlessly integrates two underlying cryptographic primitives, blind signature and hash chain, into a highly flexible and lightweight authentication and key establishment protocol. It provides explicit mutual authentication and allows multiple current sessions between a user and a service, while allowing the user to anonymously interact with the service. The proposed scheme is also designed to be DoS resilient by requiring the user to prove her legitimacy when initializing a service session.

An efficient two‐party authentication key exchange protocol for mobile environment

The primary goal of this research is to ensure secure communications by client‐server architectures in mobile environment. Although various two‐party authentication key exchange protocols are proposed and claimed to be resistant to a variety of attacks, studies have shown that various loopholes exist in these protocols. What's more, many two‐party authentication key exchange protocols use timestamp to prevent the replay attack and transmit the user's identity in plaintext form. Obviously, these methods will lead to the clock synchronization problem and user's anonymity problem. Fortunately, the three‐way challenged‐response handshake technique and masking user's original identity with a secret hash value used in our study address these problems well. Of course, the proposed protocol based on elliptic curve cryptography supports flawless mutual authentication of participants, agreement of session key, impersonation attack resistance, replay attack resistance, and prefect forward secrecy, as well. The analyses in the aspects of efficiency and security show that the proposed protocol is a better choice for mobile users.     

Privacy‐preserving authentication scheme for on‐road on‐demand refilling of pseudonym in VANET

Privacy in Vehicular Ad Hoc Networks (VANET) is fundamental because the user's safety may be threatened by the identity and the real‐time spatiotemporal data exchanged on the network. This issue is commonly addressed by the use of certified temporal pseudonyms and their updating strategies to ensure the user's unlinkability and anonymity. IEEE 1609.2 Standard specified the process of certifying pseudonym along with certificates structure. However, the communication procedure between the certifying authority and the requesting vehicle was not defined. In this paper, a new privacy‐preserving solution for pseudonym on‐road on‐demand refilling is proposed where the vehicle anonymously authenticates itself to the regional authority subsidiary of the central trusted authority to request a new pseudonyms pool. The authentication method has two phases, the first one uses anonymous tickets, and the second one is a challenge‐based authentication. The anonymous tickets are certificates that do not include the identity of the user. Instead, it contains a reference number and the certifying authority signature. The challenge authentication is identity‐less to preserve the privacy, yet it is used to prevent the misuse of tickets and the impersonation of its owner. Our proposed scheme is analyzed by the use of Burrows, Abadi and Needham (BAN) logic to demonstrate its correctness. It is also specified and checked by using the Security Protocol ANimator (SPAN) and the Automated Validation of Internet Security Protocols and Applications (AVISPA) tools. The logical demonstration proved that this privacy‐preserving authentication is assured. The SPAN and AVISPA tools illustrated that it is resilient to security attacks.     

Revised anonymous authentication protocol for adaptive client‐server infrastructure

Rapid evolution in information and communication technologies has facilitated us to experience mobile communication in our daily routine. Mobile user can only avail the services from the server, once he/she is able to accomplish authentication process successfully. In the recent past, several researchers have contributed diverse authentication protocols for mobile client‐server environment. Currently, Lu et al designed two‐factor protocol for authenticating mobile client and server to exchange key between them. Lu et al emphasized that their scheme not only offers invincibility against potential security threats but also offers anonymity. Although this article reveals the facts that their protocol is vulnerable against client and server impersonation, man‐in‐the‐middle, server key breach, anonymity violation, client traceability, and session‐specific temporary attacks, therefore, we have enhanced their protocol to mitigate the above mention vulnerabilities. The enhanced protocol's security strength is evaluated through formal and informal security analysis. The security analysis and performance comparison endorses the fact that our protocol is able to offer more security with least possible computation complexity.     

Design of a user anonymous password authentication scheme without smart card

Recently, Jiang et al. and He et al. independently found security problems in Chen et al.'s remote user authentication scheme for non‐tamper‐proof storage devices like Universal Serial Bus stick and proposed improvements. Nonetheless, we detect that the schemes proposed by Jiang et al. and He et al. overlook a user's privacy. We also observe that Jiang et al.'s scheme is vulnerable to insider attack and denial of service attacks and lacks forward secrecy. We point out that the password changing facility in He et al.'s scheme is equivalent to undergoing registration, whereas in Jiang et al.'s scheme, it is unsuitable. Moreover, the login phase of both the schemes is incapable to prevent the use of wrong password leading to the computation of an unworkable login request. Therefore, we design a new scheme with user anonymity to surmount the identified weaknesses. Without adding much in communication/computational cost, our scheme provides more security characteristics and keeps the merits of the original schemes. As compared with its predecessor schemes, the proposed scheme stands out as a more apt user authentication method for common storage devices. We have also presented a formal proof of security of the proposed scheme based on the logic proposed by Burrows, Abadi and Needham (BAN logic). Copyright © 2014 John Wiley & Sons, Ltd.     

A PTD‐based transaction protocol for public transportation

Advances in wireless network technology and the increasing number of users of the personal trusted device (PTD) make the PTD an ideal channel for offering personalized services to mobile users. In this paper, we propose using a PTD as a payment tool in a mobile transaction system for public transportation. To overcome the inherent weakness of computing resources in a PTD, we use a trusted observer to coordinate the mobile transaction and to integrate cryptology (such as a digital signature and a one‐way hash function). The proposed scheme satisfies the requirements for mobile transactions. These requirements include fairness, non‐repudiation, anonymity, off‐line capability, no forgery, efficient verification, simplicity, and practicability. Because a PTD is more portable and personal than a personal computer and because the public transportation can be a necessity in our daily lives, our scheme proposes a novel use of PTDs in mobile commerce. Copyright © 2008 John Wiley & Sons, Ltd.     

个人移动数据收集中的多维轨迹匿名方法

在情景感知位置服务中,移动互联网络的开放性使得个人移动数据面临巨大的安全风险,移动数据的时空关联特性对个人数据的隐私保护提出重大挑战.针对基于时空关联的背景知识攻击,本文提出了一种多维的轨迹匿名隐私保护方法.该方法在匿名轨迹数据收集系统的基础上,基于多用户协作的隐私保护模式,通过时间匿名和空间匿名算法,实现用户的隐私保护.实验结果表明,该方法可以有效的对抗基于位置和移动方式的背景知识攻击,满足了k-匿名的隐私保护要求.