Identity-based Cryptosystem Research Articles

On the Challenges in Designing Identity-Based Privacy-Preserving Authentication Schemes for Mobile Devices

Providing secure, efficient, and privacy-preserving user authentication in mobile networks is a challenging problem due to the inherent mobility of users, variety of attack vectors, and resource-constrained nature of user devices. Recent studies show that identity-based cryptosystems can eliminate the certificate overhead and thus address the issues associated with public-key infrastructure technology—which is a rare bit of good news in today's computer security world. In this paper, we employ three representative identity-based remote user authentication schemes (i.e., Truong et al. 's scheme, Li et al. 's scheme, and Zhang et al. 's scheme) as case studies to reveal the challenges and subtleties in designing a practical authentication scheme for mobile devices. First, we demonstrate that Truong et al. 's scheme, which was presented at the IEEE AINA 2012, cannot achieve a few important security goals under our new attacking scenarios: 1) it fails to resist against known session-specific temporary information attack; 2) it cannot withstand key compromise impersonation attack; and 3) it is of poor usability. Second, we show that Li et al. 's privacy-preserving scheme, which was proposed at GLOBECOM 2012, is subject to some subtle (yet severe) efficiency problems that make it virtually impossible for any practical use. Third, we scrutinize a “provably secure” scheme for roaming services in mobile networks designed by Zhang et al. at SCN 2015 and find it prone to collusion attack and replay attack. Further, we investigate into the underlying causes for these identified failures, and figure out an improvement over Truong et al. 's scheme to overcome the revealed challenges while maintaining reasonable efficiency.

Cognitive-based routing model with identity-based cryptography in MANET

In MANET, trust-based routing algorithm is the major protocol for selecting optimal route path. The optimal path is selected based on the available maximum path trust value in the network and the transmission is occurred through this selected trust path. This kind of transmission should be securable and energy efficient. So, in this paper we have exhibited a trust model for routing with identity-based cryptography in MANET. For effective course way choice we have proposed cognitive agent-based trust model. Cognitive agents are the self-sufficient projects which sense the environment, follow up on nature, and utilise its information to accomplish their goal(s). This cognitive agent is developed with the behaviours-observations-beliefs (BOB) model to assess the convictions or trust esteem for every node in MANET. For securable transmission, likewise we have proposed identity-based cryptography. In identity-based cryptosystem, confirmation of client's legitimacy is accomplished by its one of a unique identifier (ID). Private key produces from a private key generator (PKG) while the public key is acquired from client's ID. From the simulation results, we show that better packet delivery ratio, energy consumption, throughput compared to the previous work.

An ID-Based Linearly Homomorphic Signature Scheme and Its Application in Blockchain

Identity-based cryptosystems mean that public keys can be directly derived from user identifiers, such as telephone numbers, email addresses, and social insurance number, and so on. So they can simplify key management procedures of certificate-based public key infrastructures and can be used to realize authentication in blockchain. Linearly homomorphic signature schemes allow to perform linear computations on authenticated data. And the correctness of the computation can be publicly verified. Although a series of homomorphic signature schemes have been designed recently, there are few homomorphic signature schemes designed in identity-based cryptography. In this paper, we construct a new ID-based linear homomorphic signature scheme, which avoids the shortcomings of the use of public-key certificates. The scheme is proved secure against existential forgery on adaptively chosen message and ID attack under the random oracle model. The ID-based linearly homomorphic signature schemes can be applied in e-business and cloud computing. Finally, we show how to apply it to realize authentication in blockchain.

Cryptanalysis and Enhancement of an Anonymous Self-Certified Key Exchange Protocol

Authentication protocols with anonymity have gained much popularity recently which allows users to access any public network without compromising their identity. Several key exchange protocols have been proposed in the literature using either public key infrastructure or identity-based cryptosystem. However, the former suffers from heavy computation cost and latter fails to prevent key escrow problem. Recently, Islam et al. have proposed a self-certified authenticated key agreement protocol based on ECC which removes the above limitations. However, through careful analysis, we found that their scheme lack anonymity and vulnerable to trace the attack, clogging attack, and fails to prevent the replay attack. To overcome these weaknesses, we propose an anonymous self-certified authenticated key exchange protocol by including the required security features. The scheme is formally proved using Automated Validation of Internet Security protocols and Applications software. Also, the formal authentication proofs using Burrows–Abadi–Needham logic ensures successful authentication. Furthermore, the performance analysis demonstrates that the proposed scheme accomplishes less computational cost and is applicable to a client–server architecture.

Certificate‐based signature scheme in the standard model

Certificate-based cryptosystem can eliminate the private key escrow problem inherent in the identity-based cryptosystem and can simplify the costly certificate management in the traditional public key cryptosystem. In 2016, Lu et al. raised an open problem of whether the certificate-based signature (CBS) scheme can be proved secure against the malicious-but-passive certifier attack. In this study, the authors try to solve this problem. They give an enhanced security model of the CBS scheme which can resist the malicious-but-passive certifier attack. Then they propose a concrete CBS scheme in the standard model by using bilinear pairings. They prove the scheme to be secure in the enhanced security model under the Squ-CDH assumption. In this way, the authors give an affirmative answer to the above open problem. Finally, the authors evaluate the efficiency of the scheme which shows it to be practical. In addition, they find that malicious-but-passive certifier security cannot coexist with super adversary security in a CBS scheme in the standard model.

Constructing ID-based cryptographic technique for IFP and GDLP based cryptosystem

Shamir developed an idea of the ID-based cryptographic technique in 1984 [1]. In its place of making and issuing a public key for each user, the ID-based cryptographic scheme authorized each user to choose his name or network address etc. as his public key. The public-key verification is so easy and direct by using the advantage of public key cryptosystem. In this study, we proposed the new ID-based cryptographic scheme for applying public-key cryptosystem based on Integer Factorization Problem (IFP) and Generalized Discrete Logarithm Problem (GDLP). The main benefit of the ID-based cryptographic technique based on our proposed scheme over other published ID-based cryptosystems in the literature, is that the number of users can be extended to a * L users without undignified the system's security even when users plan, where L and a are the system's private keys and factors in N – 1 respectively.

A Novel Identity-Based Signcryption Scheme in the Standard Model

Identity-based signcryption is a useful cryptographic primitive that provides both authentication and confidentiality for identity-based crypto systems. It is challenging to build a secure identity-based signcryption scheme that can be proven secure in a standard model. In this paper, we address the issue and propose a novel construction of identity-based signcryption which enjoys IND-CCA security and existential unforgeability without resorting to the random oracle model. Comparisons demonstrate that the new scheme achieves stronger security, better performance efficiency and shorter system parameters.

Multi-message and multi-receiver heterogeneous signcryption scheme for ad-hoc networks

ABSTRACTSecurity is a significant issue for ad-hoc networks. Heterogeneous signcryption schemes proposed in recent years satisfy privacy and authentication of messages and reduce cost of computation and communication in a logical step. In this article, we present a new efficient heterogeneous signcryption scheme that shifts between the public key infrastructure (PKI) and the identity-based cryptosystem (IBC). The proposed scheme is suitable for broadcast communication conditions in which senders can signcrypt multiple messages for multiple receivers simultaneously in the ad-hoc networks. This scheme is proved to satisfy confidentiality and unforgeability on the basis of the assumptions of bilinear Diffie-Hellman problem (BDHP), q-Diffie-Hellman inversion problem (q-DHIP), q-bilinear Diffie-Hellman inversion problem (q-BDHIP), and computational Diffie-Hellman problem (CDHP) in the random oracle model. We discuss the efficiency of our scheme theoretically. In the efficiency analysis phase, we show that our scheme is practical and efficient. In the performance analysis phase, we present additional tests, data, and explanations to prove that our scheme can be applied in ad-hoc networks. Finally, we apply our scheme to a simulated ad-hoc network.

A PUF-Based Secure Communication Protocol for IoT

Security features are of paramount importance for the Internet of Things (IoT), and implementations are challenging given the resource-constrained IoT setup. We have developed a lightweight identity-based cryptosystem suitable for IoT to enable secure authentication and message exchange among the devices. Our scheme employs a Physically Unclonable Function (PUF) to generate the public identity of each device, which is used as the public key for each device for message encryption. We have provided formal proofs of security in the Session Key Security and Universally Composable Framework of the proposed protocol, which demonstrates the resilience of the scheme against passive and active attacks. We have demonstrated the setup required for the protocol implementation and shown that the proposed protocol implementation incurs low hardware and software overhead.

A new certificateless multiple key agreement scheme

Recently, by changing security requirements of computer networks, many public key schemes are introduced. One major shortcoming of identity-based cryptosystems is key screw. Certificateless public key cryptosystems were introduced to solve this problem. In this paper, a certificateless, public-key, multiple-key-agreement scheme will be offered which has some significant security properties such as perfect forward secrecy, strong security, and zero-knowledge proof. This scheme produces far more shared hidden keys per session in comparison with many existing schemes. In this paper, the security and the efficiency of the proposed scheme will be compared with some well-known current schemes.

Efficient Revocable ID-Based Signature With Cloud Revocation Server

Over the last few years, identity-based cryptosystem (IBC) has attracted widespread attention because it avoids the high overheads associated with public key certificate management. However, an unsolved but critical issue about IBC is how to revoke a misbehaving user. There are some revocable identity-based encryption schemes that have been proposed recently, but little work on the revocation problem of identity-based signature has been undertaken so far. One approach for revocation in identity-based settings is to update users’ private keys periodically, which is usually done by the key generation center (KGC). But with this approach, the load on the KGC will increase quickly when the number of users increases. In this paper, we propose an efficient revocable identity-based signature (RIBS) scheme in which the revocation functionality is outsourced to a cloud revocation server (CRS). In our proposed approach, most of the computations needed during key-updates are offloaded to the CRS. We describe the new framework and the security model for the RIBS scheme with CRS and we prove that the proposed scheme is existentially unforgeable against adaptively chosen messages and identity attacks in the random oracle model. Furthermore, we monstrate that our scheme outperforms previous IBS schemes in terms of lower computation and communication costs.

An efficient revocable ID-based encryption scheme in the standard model

Similar to the traditional public key setting based on public key infrastructure, in the application of identity-based cryptosystems, it is also important to provide a practical mechanism for revoking those users whose private keys are compromised or they are no longer legitimate system users. This paper concentrates on the practical user revocation problem in identity-based encryption (IBE) systems. We present an efficient and CCA2 secure revocable identity-based encryption (RIBE) scheme in the standard model. The revocation mechanism put forward in our RIBE scheme does not require secure channels between the PKG and the users. The CCA2 security of our scheme is rigorously proved and is tightly reduced to the hardness assumption of the decisional truncated q-ABDHE problem without using random oracles. Additionally, our RIBE scheme also supplies a mechanism that permits the revoked users to rejoin the system without altering their identity information or rebuilding the system.

Comparative analysis of applications of identity-based cryptosystem in IoT

Comparative analysis of applications of identity-based cryptosystem in IoT

An Efficient Heterogeneous Signcryption Scheme from Certificateless to Identity-based Cryptosystem

The heterogeneous signcryption can not only realize the confidentiality and un-forgeability of the information transmission between different public key cryptography environments, but also reduce the communication cost. The proposed scheme uses bilin-ear pairings between certificateless cryptography and identity-based cryptography to construct a heterogeneous signcryption scheme. In addition, two cryptography systems use different secret master keys. Furthermore, the proposed scheme has the indistin-guishability against adaptive chosen ciphertext attacks and existential unforgeability against adaptive chosen-message attacks in the random oracle model. Through the data analysis, this scheme is more effective than other similar types of scheme.

Certificateless Signcryption in the Standard Model

Signcryption can realize encryption and signature simultaneously with lower computational costs and communicational overheads than those of the traditional sign-then-encrypt approach. Certificateless cryptosystem solves the key escrow problem in the identity-based cryptosystem and simplifies the public key management in the traditional public key cryptosystem. There have been some certificateless signcryption schemes proposed in the standard model up to now, but all of them are just proposed in a weaker Type I security model, which is weaker than the original security model of Barbosa and Farshim, who proposed the first certificateless signcryption scheme. In this paper, we propose a certificateless signcryption scheme in the standard model by using bilinear pairings, which is Type I secure in the original security model of Barbosa and Farshim and can resist the malicious-but-passive key generation center Type II attack. The proposed scheme is proved confidential assuming the modified decisional bilinear Diffie---Hellman (M-DBDH) problem is hard, and unforgeable assuming the square computational Diffie---Hellman (Squ-CDH) problem is hard. At last, we evaluate its efficiency which shows it is of high efficiency.

A new framework for implementing identity-based cryptosystems

Identity-Based Encryption (IBE) suffers from the problem of trust in the Private Key Generator (PKG), which translates into the ability of the PKG to produce and distribute multiple private keys or multiple copies of a single key without knowledge of the genuine user. This problem makes the deployment of these systems limited to areas where trust in the PKG must have a high level. Many works addressed this problem and proposed a wide range of key generation protocols which grew from simple protocols run between user and PKG to complex and interactive protocols involving distributed computations. However, the implementation of such complex protocols requires much programming efforts and the few existing tools and libraries deal with special case protocols.In this paper, we present the first complete, efficient and modular framework, composed of a set of libraries, which brings together the most known techniques of private-key generation for identity-based cryptosystems. Our framework aims at providing robust tools designed in a modular and reusable manner to allow developers to implement the latest results coming from theoretical cryptography.

Secure Route Optimization Scheme for Network Mobility Support in Heterogeneous Mobile Networks

With the proliferation of various wireless services such as Third Generation, Fourth Generation, Wireless Local Area Network, and Personal Area Network, etc., users request for access to the Next Generation Internet in more heterogeneous networks. The network mobility working group within the Internet Engineering Task Force introduced the Network Mobility (NEMO) concept as a network mobility basic support protocol (i.e., network moves as a unit) extended from Mobile IPv6 (MIPv6). However, this solution has the limitation of route optimization that should be always passed by Home Agents (HAs) using a bi-directional tunnel with its Mobile Router (MR). It is not also entirely supported a security requirements and various attacks (e.g., Denial of Service attack, redirect attack, etc.). Most of all, it is not mentioned how authentication issues between a HA and a Correspondent Node (CN) are solved in NEMO environments. To ameliorate these problems, we propose novel authenticated route optimization scheme to be performed by MR and CN of Mobile Network Nodes, which uses IDentity-based cryptosystem (that is, a Multi-Private Key Generator Based Authenticated Key Agreement between MRs) to look upon heterogeneous NEMO environments. In performance analysis, we analytically compute the protocol's connectivity recovery and end-to-end delay time and then compare the security and the efficiency of proposed scheme with the NEMO Basic support protocol, i.e., RFC 3963.

Unconditionally Anonymous Controllable ID-Based Ring Signatures

ID-Based ring signatures are result of application of ID-Based cryptosystems to ring signature schemes. The contribution of this paper is twofold. At first the paper introduces a new variant of ID-based ring signatures named as controllable ID-Based ring signatures (CIBRS). This new primitive has additional properties like control linkability, anonymous authorship and convertibility. Formal definitions of these properties and the security model for the new primitive were presented. Secondly, the paper presents the first unconditionally anonymous CIBRS scheme from Chow et al.’s [4] scheme. The proposed scheme uses control linkability to achieve high efficiency of computation and storage. In the proposed scheme, to generate k signatures, a member of an n-member-ring needs only n+k scalar point multiplications and 2n+k-1 hash computations when compared to kn operations of Chow et al.’s scheme. Also, to verify k signatures the scheme requires only 2 pairing operations and n+k-1 hash computations compared to 2k and nk operations respectively. Link-signatures due to the proposed scheme are independent of size of the ring. Using the link-signatures our scheme achieves a significant signature size of 3(n+k)-1 compared to 2k(n+1) (in the units of size of the field element). The scheme provides unconditional anonymity and uncontrollability to the signer even in case of compromise of the key-escrow.

Round-Efficient and Sender-Unrestricted Dynamic Group Key Agreement Protocol for Secure Group Communications

Modern collaborative and group-oriented applications typically involve communications over open networks. Given the openness of today’s networks, communications among group members must be secure and, at the same time, efficient. Group key agreement (GKA) is widely employed for secure group communications in modern collaborative and group-oriented applications. This paper studies the problem of GKA in identity-based cryptosystems with an emphasis on round-efficient, sender-unrestricted, member-dynamic, and provably secure key escrow freeness. The problem is resolved by proposing a one-round dynamic asymmetric GKA protocol which allows a group of members to dynamically establish a public group encryption key, while each member has a different secret decryption key in an identity-based cryptosystem. Knowing the group encryption key, any entity can encrypt to the group members so that only the members can decrypt. We construct this protocol with a strongly unforgeable stateful identity-based batch multisignature scheme. The proposed protocol is shown to be secure under the $k$ -bilinear Diffie–Hellman exponent assumption.

Embedding an Identity-Based Short Signature as a Digital Watermark

Digital watermarking aims at protecting multimedia content by hiding into it some data that can be used for such purposes as, for example, intellectual property protection or integrity control. Sometimes, the owner of an image would prefer to not transmit, publish, or hand to a cloud service the original image, but rather an encrypted version of it. Encrypted images allow for less embedding room with respect to their unencrypted counterparts, as there is less spatial correlation to leverage upon. An architecture for embedding as payload the digital signature of an encrypted image, by means of a reversible watermarking technique, is presented in this work. A noteworthy point is the use of an identity-based cryptosystem to avoid certificate management and improve performance. In addition, the use of IBS-1, a recently proposed signature scheme, allows for a reduction in the size of the signature.