Maged Hamada Ibrahim

Anonymous mutual authentication and key agreement scheme for wearable sensors in wireless body area networks

Abstract Wireless body area networks (WBANs) are used to collect and exchange vital and sensitive information about the physical conditions of patients. Due to the openness and mobility of such networks, even without knowing the context of the exchanged data or linking traffic to the identities of involved sensors, criminals are able to gain useful information about the severe conditions of patients and carry effective undetectable physical attacks. Therefore, confidentiality and mutual authentication services are essential for WBANs, and the transmission must be anonymous and unlinkable as well. Given the limitations of the resources available for these sensors, a lightweight anonymous mutual authentication and key agreement scheme for centralized two-hop WBANs is proposed in this paper, which allows sensor nodes attached to the patient’s body to authenticate with the local server/hub node and establish a session key in an anonymous and unlinkable manner. The security of our scheme is proved by rigorous formal proof using BAN logic and also through informal analysis. Besides, the security of our scheme is evaluated by using the Automated Validation of Internet Security Protocols and Applications (AVISPA) as well. Finally, we compare our proposed scheme with other related schemes and the comparison results show that our scheme outperforms previously related schemes.

Receiver-deniable Public-Key Encryption

Incoercible (or deniable) encryption is an important notion that allows a user (a sender and/or a receiver) to escape a coercion attempted by a coercive adversary. Such an adversary approaches the coerced user after transmission forcing him to reveal all his random inputs used during encryption or decryption. Since traditional encryption schemes commits the user to his random inputs, the user is forced to reveal the true values of all his random inputs (including the encrypted/decrypted messages and the encryption/decryption keys) which are verifiable by this coercer using the intercepted ciphertext. In this scenario, a coercer may force the user to perform actions against his wish. An appealing property in the mediated RSA PKI introduced in [2] is that, the user has no in- formation, neither about his full private (decryption) key, nor the factorization of the RSA public modulus, which represents an excellent step toward achieving incoercibility in public key encryption, since, a coercer cannot ask the user to reveal such unknown information. In this pa- per we present a scheme for receiver-deniable public-key encryption, by which, the receiver is able to lie about the decrypted message to a coercer and hence, escape a coercion. On one hand, the receiver is able to decrypt for the correct message, on the other hand, all the information held by the receiver, when opened to a coercer, do not allow this coercer to verify the encrypted message and consequently, approaching this user becomes useless from the very beginning.

Secure anonymous mutual authentication for star two-tier wireless body area networks

BACKGROUND AND OBJECTIVES Mutual authentication is a very important service that must be established between sensor nodes in wireless body area network (WBAN) to ensure the originality and integrity of the patients data sent by sensors distributed on different parts of the body. However, mutual authentication service is not enough. An adversary can benefit from monitoring the traffic and knowing which sensor is in transmission of patients data. Observing the traffic (even without disclosing the context) and knowing its origin, it can reveal to the adversary information about the patients medical conditions. Therefore, anonymity of the communicating sensors is an important service as well. Few works have been conducted in the area of mutual authentication among sensor nodes in WBAN. However, none of them has considered anonymity among body sensor nodes. Up to our knowledge, our protocol is the first attempt to consider this service in a two-tier WBAN. We propose a new secure protocol to realize anonymous mutual authentication and confidential transmission for star two-tier WBAN topology. METHODS The proposed protocol uses simple cryptographic primitives. We prove the security of the proposed protocol using the widely-accepted Burrows-Abadi-Needham (BAN) logic, and also through rigorous informal security analysis. In addition, to demonstrate the practicality of our protocol, we evaluate it using NS-2 simulator. RESULTS BAN logic and informal security analysis prove that our proposed protocol achieves the necessary security requirements and goals of an authentication service. The simulation results show the impact on the various network parameters, such as end-to-end delay and throughput. The nodes in the network require to store few hundred bits. Nodes require to perform very few hash invocations, which are computationally very efficient. The communication cost of the proposed protocol is few hundred bits in one round of communication. Due to the low computation cost, the energy consumed by the nodes is also low. CONCLUSIONS Our proposed protocol is a lightweight anonymous mutually authentication protocol to mutually authenticate the sensor nodes with the controller node (hub) in a star two-tier WBAN topology. Results show that our protocol proves efficiency over previously proposed protocols and at the same time, achieves the necessary security requirements for a secure anonymous mutual authentication scheme.

Resisting Traitors in Linkable Democratic Group Signatures

Linkable democratic group signatures (LDGS) [29] allow every member of a group to trace the identity of any other member who issued a signature while non-members (with the help of unique pseudonyms) are only able to link the signatures issued by the same signer without being able to trace the signers identity. LDGS avoid centralized management authorities (group managers) and grant each group member the power to trace and identify the signer. Although LDGS add nice properties to group signatures, allowing each member of the group to trace the signers identity requires a full trust in each group member not to trace or disclose the identity of the signer without a legal reason (e.g. a dispute). Such a requirement represents a major obstacle in practice. The existence of at least one saboteur member inside the group totally violates the anonymity attribute which is the main merit of group signatures. Such a traitor may reveal the identity of the signers to non-members without being detected. In this paper we introduce a simple, yet efficient traitors resistant LDGS (TR-LDGS) as a security improvement to the LDGS scheme of [29] to resist traitors in the sense that, the power to trace and disclose the identity of the signer must not be in the hands of each member. Instead, the power to trace and identify a signer will be distributed among the members of the group such that a fraction (majority) of the members may join together to trace and reveal the signers identity while no minority coalitions are able to perform this task or to disturb the correct and legal progress of this task.

Octopus: An Edge-Fog Mutual Authentication Scheme

Authentication is an important and challenging issue for the security of Fog computing since, services are offered to massive-scale end users (Fog users or Edge) by front Fog servers (or Fog nodes). In this paper, we propose a secure and efficient mutual authentication scheme for the Edge-Fog-Cloud network architecture, to mutually authenticate Fog users at the Edge of the network, with the Fog servers at the Fog layer. Our scheme requires a user － roaming randomly in the network { to hold only one long-lived master secret key (with long enough bit-length) allowing him to communicate with any of the Fog servers in the network, in a fully authenticated way. The Fog users are able to mutually authenticate with new Fog servers joining the network, without the need to re-register and without any extra overheads. Moreover, the servers in the Fog are required to store only one secret key for each Fog user. On the other hand, the Fog users are totally unrelated to any public-key infrastructure. The scheme requires the Fog user to perform very few hash invocations and symmetric encryptions/decryptions. Therefore, the scheme is suitable to be efficiently implemented on the Fog users smart card/device.

Non-interactive Authentication Scheme Providing Privacy among Drivers in Vehicle-to-Vehicle Networks

In this paper, we present a non-interactive authentication scheme providing privacy among drivers in vehicle-to-vehicle (V2V) communication networks. Where the drivers, who are members of V2V networks, are organized into groups. Each group has a shared public key between members. Additionally, each member has a private key provided by the Third Trusted Party (TTP). In our proposed scheme, we ensure drivers privacy by allowing members to change their own set of public keys frequently using the Digital Signature Algorithm (DSA). The TTP sends to each member a token of his original set of public keys. This member can find non-interactively a new token corresponding to the new set of public keys, and hence vehicles can exchange the safety critical information without requiring a control from the TTP. In case of a malicious behavior, the identity of the signer can be revealed only by the TTP.

Improving security and efficiency of enterprise digital rights management

Recently, private enterprises, governmental and military institutions have been relied mainly on digitizing their work. Digital files containing sensitive information should be protected against external and internal malicious attacks. Enterprise digital rights management (E-DRM) schemes provides several approaches to protect and securely distribute digital contents while empowering the enterprises administration to monitor and control access to these contents. In this paper we propose a new secure and efficient E-DRM system based on the Information Dispersal Algorithm (IDA). We achieved an improvement in the overall storage requirements, and the computations complexity at each server in the system, as well as preserving the security of information and system robustness.

Non-interactive Secure and Privacy Preserving Protocol for Inter-vehicle Communication Networks

In this paper, we introduce a non-interactive secure protocol preserving privacy of the drivers for Inter-Vehicle Communication (IVC) networks. To protect the privacy among drivers, we propose to arrange vehicles into several groups. Vehicles in a group share the same public key, but each member can change his own set of public keys frequently, so the receiving vehicle cannot identify an individual driver in the group. In addition, each member has a private key provided by the Third Trusted Party (TTP) to enable the TTP, who is assumed to be fully trusted, to trace the driver who sends malicious information. Then, the TTP computes a fixed token of all members in the same group, but only participants in IVC networks can convince the receiving vehicle that the token is corresponding to their changed public keys set. So, we can achieve authentication.

Secure and efficient anonymous authentication scheme for three-tier mobile healthcare systems with wearable sensors

The mobility and openness of wireless communication technologies make Mobile Healthcare Systems (mHealth) potentially exposed to a number of potential attacks, which significantly undermines their utility and impedes their widespread deployment. Attackers and criminals, even without knowing the context of the transmitted data, with simple eavesdropping on the wireless links, may benefit a lot from linking activities to the identities of patient’s sensors and medical staff members. These vulnerabilities apply to all tiers of the mHealth system. A new anonymous mutual authentication scheme for three-tier mobile healthcare systems with wearable sensors is proposed in this paper. Our scheme consists of three protocols: Protocol-1 allows the anonymous authentication nodes (mobile users and controller nodes) and the HSP medical server in the third tier, while Protocol-2 realizes the anonymous authentication between mobile users and controller nodes in the second tier, and Protocol-3 achieves the anonymous authentication between controller nodes and the wearable body sensors in the first tier. In the design of our protocols, the variation in the resource constraints of the different nodes in the mHealth system are taken into consideration so that our protocols make a better trade-off among security, efficiency and practicality. The security of our protocols are analyzed through rigorous formal proofs using BAN logic tool and informal discussions of security features, possible attacks and countermeasures. Besides, the efficiency of our protocols are concretely evaluated and compared with related schemes. The comparisons show that our scheme outperforms the previous schemes and provides more complete and integrated anonymous authentication services. Finally, the security of our protocols are evaluated by using the Automated Validation of Internet Security Protocols and Applications and the SPAN animator software. The simulation results show that our scheme is secure and satisfy all the specified privacy and authentication goals.

Attribute-based authentication on the cloud for thin clients

We propose two new authentication schemes for the cloud that support private attribute-based authentication services. The basic scheme is non-anonymous attribute-based authentication scheme. The extended scheme of the basic scheme is fully anonymous attribute-based authentication scheme to realize full anonymity and unlinkability services. In the proposed schemes, a user is authenticated by the remote server if the intersection of the set of his/her assigned attributes and the server’s required attributes exceeds a satisfactory predefined level. Unlike existing attribute-based encryption and signature schemes that require the user to perform significant amount of elliptic curve bilinear pairings and modular exponentiations, and require the user to hold a significantly long decryption/signature key, in our schemes the user is not required to perform any bilinear pairings. With a fixed length private key, independent of the number of attributes, the cloud user performs only few exponentiations by which he/she is able to authenticate himself/herself to the remote server and establish a session key with the server with the condition that he/she satisfies a predefined level of the server’s attributes requirement. Therefore, our schemes are suitable for implementation on devices with limited resources. We provide the rigorous security of the proposed schemes and complexity analysis of our schemes. Finally, the security and performance comparisons of our schemes with the existing related schemes show that our schemes outperform other existing schemes.