Receiver Anonymity Research Articles

Comment on an Attribute-Based Searchable Encryption Scheme With Receiver Anonymity

Comment on an Attribute-Based Searchable Encryption Scheme With Receiver Anonymity

Generic Construction of Fully Anonymous Broadcast Authenticated Encryption with Keyword Search with Adaptive Corruptions

As a multireceiver variant of public key authenticated encryption with keyword search (PAEKS), broadcast authenticated encryption with keyword search (BAEKS) was proposed by Liu et al. (ACISP 2021). BAEKS focuses on receiver anonymity, where no information about the receiver is leaked from ciphertexts, which is reminiscent of the anonymous broadcast encryption. Here, there are rooms for improving their security definitions, e.g., two challenge sets of receivers are selected before the setup phase, and an adversary is not allowed to corrupt any receiver. In this paper, we propose a generic construction of BAEKS derived from PAEKS that provides ciphertext anonymity and consistency in a multireceiver setting. The proposed construction is an extension of the generic construction proposed by Libert et al. (PKC 2012) for the fully anonymous broadcast encryption and provides adaptive corruptions. We also demonstrate that the Qin et al. PAEKS scheme (ProvSec 2021) provides ciphertext anonymity and consistency in a multireceiver setting and can be employed as a building block of the proposed generic construction.

Lagrangian Recurrent Steganalysis and Hyper Elliptic Certificateless Signcryption for Secure Image Transmission

Present-day evolution in communication and information technology dispenses straightforward and effortless access to data, but the most noteworthy condition is the formation of secure communication. Numerous approaches were designed for safety communication. One of the crucial approaches is image steganography. Moreover, provisioning of information security services is arrived at via cryptosystems where cryptosystems make certain the secure messages transmission between the users in an untrustworthy circumstance. The conventional method of providing encryption and signature is said to be first signing and then encryption, but both the computation and communication costs are found to be high. A certificateless signcryption mechanism is designed to transfer the medical data or images securely. This mechanism will minimize the storage and verification costs of public key certificates. The author of this article proposes a method named Lagrangian recurrent Steganalysis and Hyper Elliptic Certificateless Signcryption for transferring the medical data or images securely. In two sections the LRS-HECS method is split. They are medical image steganalysis and certificateless signcryption. First with the Chest X-Ray images obtained as input, a Codeword Correlated Lagrangian Recurrent Neural Network-based image steganography model is applied to generate steg images. Second, to transfer the medical images securely the steg images provided as input is designed a model named a Hyper Elliptic Curve-based Certificateless Signcryption. The issue of providing the integrity and validity of the transmitted medical images and receiver anonymity is addressed by the application of Hyper Elliptic Curve. Chest X-Ray pictures were used in experimental simulations, and the findings showed that the LRS-HECS approach had more advantages over existing state-of-the-art methods in terms of higher peak signal to noise ratio with data integrity and with reduced encryption time and transmission cost.

Certificateless Broadcast Encryption with Authorization Suitable for Storing Personal Health Records

Abstract Cloud medical treatment provides real-time data sharing in a cost-effective method, making it more practical to create, collect and manage vast amounts of personal health records (PHR) of patients. However, health information is considered highly sensitive. How to securely store and dynamically process massive patients’ PHR data in a public cloud environment has become one of the most important challenges. Therefore, we introduce a novel solution to the problems of privacy exposure, data security and flexible access of storage modules in medical systems. In this paper, we present a privacy-preserving certificateless broadcast encryption with authorization for the PHR system, which is the best approach to effectively solve the above problems and avoid key escrow. In our work, users (patients) outsource their encrypted data to the cloud server and reallocate data accessing rights of recipients through an authorization set, sharing with a group of authorized receivers (doctors) in a secure and efficient manner. In addition, it is shown to be capable of achieving both plaintext confidentiality and receiver anonymity under the random oracle model. Moreover, the experimental evaluation shows that the proposed scheme enjoys low computational and communication overhead, indicating the feasibility and practicality of the scheme.

Completely Anonymous Certificateless Multi-Receiver Signcryption Scheme with Sender Traceability

Certificateless multi-receiver signcryption scheme provides an efficient solution for one-to-many communication applications and avoids the key escrow problem in the existing identity-based multi-receiver signcryption schemes. Many certificateless multi-receiver signcryption schemes have been proposed with various secure properties, such as receiver anonymity and sender anonymity. However, among the existing certificateless multi-receiver signcryption schemes with sender anonymity, there is no scheme considers the sender tracing functionality. Sender anonymity is vulnerable and contradicts with non-repudiation. The anonymous sender may disavow the illegal message he has sent, which compromises the non-repudiation, so there is a high desirability to provide a sender tracing functionality which can be execute under certain conditions to balance the sender anonymity and non-repudiation. Motivated by these concerns, a new certificateless multi-receiver signcryption scheme is proposed, which achieves completely anonymity and provides the sender tracing functionality. In the proposed scheme, the key generation center can cooperate with any authorized receiver to trace the anonymous sender, but neither of them can do it alone. In this case, sender anonymity and non-repudiation reach a certain degree of balance.

BPRT: A blockchain‐based privacy‐preserving transaction scheme based on an efficient broadcast encryption with personalized messages

AbstractAs blockchain has drawn more and more attention, much research has developed different transaction schemes with privacy preserving specialized in various fields. The nature of blockchain makes the transaction information public, which presents much risk about the leakage of user privacy. It is quite necessary to design a flexible scheme to provide privacy preserving of transaction contents with reliable audit in blockchain that is lacked in the previous works. In this paper, we propose a blockchain‐based privacy‐preserving transaction scheme based on an efficient broadcast encryption with personalized messages called BPRT. First, we propose a fully anonymous broadcast encryption with personalized messages (BEPM). Compared with existing works, it is fully anonymous, and it has lower computation cost without pairing operations. It also avoids the key escrow problem existing in other BEPM schemes. Then, we construct the BPRT based on our BEPM. Our BPRT ensures the privacy preserving of transaction contents in group transmissions, and the encrypted transaction contents avoid exposing user identity information at the same time. It enables auditor to moderately and reliably make audit of transaction contents. Furthermore, we present formal security analysis of the proposed scheme. It has been proved that our scheme satisfies transaction confidentiality, receiver anonymity and audit reliability. Subsequently, experimental results indicate that the proposed BEPM enables fast encryption and decryption, and the computation of our BPRT is in milliseconds.

Onion under Microscope: An in-depth analysis of the Tor Web

Tor is an open source software that allows accessing various kinds of resources, known as hidden services, while guaranteeing sender and receiver anonymity. Tor relies on a free, worldwide, overlay network, managed by volunteers, that works according to the principles of onion routing in which messages are encapsulated in layers of encryption, analogous to layers of an onion. The Tor Web is the set of web resources that exist on the Tor network, and Tor websites are part of the so-called dark web. Recent research works have evaluated Tor security, its evolution over time, and its thematic organization. Nevertheless, limited information is available about the structure of the graph defined by the network of Tor websites, not to be mistaken with the network of nodes that supports the onion routing. The limited number of entry points that can be used to crawl the network, makes the study of this graph far from being simple. In the present paper we analyze two graph representations of the Tor Web and the relationship between contents and structural features, considering three crawling datasets collected over a five-month time frame. Among other findings, we show that Tor consists of a tiny strongly connected component, in which link directories play a central role, and of a multitude of services that can (only) be reached from there. From this viewpoint, the graph appears inefficient. Nevertheless, if we only consider mutual connections, a more efficient subgraph emerges, that is, probably, the backbone of social interactions in Tor.

An Anonymous Certificateless Signcryption Scheme for Secure and Efficient Deployment of Internet of Vehicles

Internet of Vehicles (IoV) is a specialized breed of Vehicular Ad-hoc Networks (VANETs) in which each entity of the system can be connected to the internet. In the provision of potentially vital services, IoV transmits a large amount of confidential data through networks, posing various security and privacy concerns. Moreover, the possibility of cyber-attacks is comparatively higher when data transmission takes place more frequently through various nodes of IoV systems. It is a serious concern for vehicle users, which can sometimes lead to life-threatening situations. The primary security issue in the provision of secure communication services for vehicles is to ensure the credibility of the transmitted message on an open wireless channel. Then, receiver anonymity is another important issue, i.e., only the sender knows the identities of the receivers. To guarantee these security requirements, in this research work, we propose an anonymous certificateless signcryption scheme for IoV on the basis of the Hyperelliptic Curve (HEC). The proposed scheme guarantees formal security analysis under the Random Oracle Model (ROM) for confidentiality, unforgeability, and receiver anonymity. The findings show that the proposed scheme promises better security and reduces the costs of computation and communication.

Mix Networks: Existing Scenarios and Future Directions on Security and Privacy

Background: Privacy-enhancing techniques are developed in order to provide strong protection to cyberspace. These techniques aim to allow users to keep their identities hidden during the communication when they are sending an email, making payments online, browsing the Web, or posting to newsgroups. MixNet is the most practical solution for concealing identities of message and sender’s identities. Objective: It provides the sender and receiver anonymity as well as message security. The main goal of MixNet is to overcome vulnerability and enhance the performance of communication. It can efficiently handle the messages of various lengths and produce desirable results with privacy. The goal of this patent is to acquire information and concepts regarding MixNet. We also grant hints for future lookups and references. Methods : The design of MixNet depends on what the cryptosystem method is used. Symmetric and Asymmetric both are used. Other methods could be also used such as PIR, CSP and FDR model, RPC, Token-based approach, or others. Result: In this patent, we provided an overview of MixNet approaches and presented a survey on MixNet based techniques and different models. We also constructed the comparison tables as per our requirements for better understanding. For this purpose, we found a total of 120 articles related to the MixNet published between 1990 and 2018 from the most relevant scientific resources. However, only 86 papers were analyzed due to comprehensiveness and relevancy in this article. Conclusion: Focused on the security and privacy of communication and how it can be achieved. This patent also reveals research progress and research gap on MixNet.

Simple and scalable blockchain with privacy

The three primary requirements in privacy coin are sender anonymity, receiver anonymity, and transaction amount obscurity. In the process of achieving these three requirements, it can result in some side-effects. Some of the side-effects include large blockchain sizes, unpruneable blockchain, unverifiable total coin mintage, and complicated protocol. In this paper, we propose a coin privacy solution that fulfills these three requirements without side-effects. Compared to other solutions, our solution has a bigger anonymity set, easier to understand, and comes with prunable blockchain. However, transactions involving fractionation amount are rounded up to the nearest available denomination. This rounding up is acceptable because it is a similar problem with cash that been used for centuries. Our protocol is an extension of bitcoin P2PKH and CoinJoin features. The CoinJoin is secured with a CoinJoinID, which cryptographical hard to reproduce. We also have proven the security of the pruning process. Other related issues are also described in this paper.

An Anonymous Certificateless Signcryption Scheme for Internet of Health Things

Internet of Health Things (IoHT) is a hot topic of research presently, which provides a reliable and intelligent healthcare system for monitoring the physical conditions of the patients over the Internet from anywhere and anytime. The ease of time-independent interaction from geographically remote areas is a core advantage of the IoHT system, which offers preventive or proactive healthcare facilities at a lower cost. IoHT communication, on the other hand, is usually carried out with a range of low-power biomedical sensors, rendering them vulnerable to cyber-attacks and incompatible with traditional cryptographic techniques. The most critical security concern in IoHT is ensuring the authenticity of patients’ health-related messages sent over the internet. Other key concerns include receiver anonymity and forward security, which means that only the sender knows the identities of the recipients. As a result, even if the private key of senders compromised, the adversary will be unable to decrypt the ciphertext. Existing signcryption schemes that employ certificateless cryptography for the healthcare system failed to guarantee both receiver anonymity and forward security simultaneously. Therefore, in this article, we propose an anonymous certificateless signcryption scheme for IoHT applications, which is based on the notion of the Hyperelliptic Curve (HEC) cryptosystem to satisfy these security requirements. The proposed scheme guarantees formal security analysis for confidentiality, unforgeability, and receiver anonymity using the Random Oracle Model (ROM). The results authenticate that the proposed scheme improves security while lowering computation and communication costs.

DPHI: An improved high-speed network-layer anonymity protocol

Abstract The Internet infrastructure has not been built with security or privacy in mind. As a result, an adversary who has control over a single Autonomous System can set-up mass surveillance systems to gather meta data by passively collecting the headers of the messages they route. To solve this problem, lightweight anonymous routing protocols such as LAP, DOVETAIL and most recently PHI have been proposed which are efficient enough to be deployed in a large scale infrastructure such as the Internet. In this paper we take a closer look at PHI and introduce several de-anonymization attacks malicious nodes can perform to reduce the sender and receiver anonymity. As a direct consequence of this analysis we propose a new protocol called dependable PHI (dPHI). The security analysis of dPHI includes a detailed quantitative anonymity analysis that compares dPHI with PHI, LAP and HORNET. Together with the performance analysis, this allows for a good comparison of trade-offs for these anonymity protocols.

KeySea: Keyword-Based Search With Receiver Anonymity in Attribute-Based Searchable Encryption

In modern digital age, enterprise applications typically outsource user data in pubic cloud storage with the objective of availing flexibility and scalability features of cloud infrastructure, and importantly, making business goal more cost effective. Security and privacy concerns pose a challenging task to handle in cloud setup by both service providers and service consumers. In this landscape, before outsourcing the sensitive data on cloud storage, the data should be protected from unauthorized access and the privacy of the users should be preserved as per application requirement. In this article, we present a scheme, termed as KeySea, keyword-based search over attribute-based encrypted data with receiver anonymity. While searching documents pertaining to the target keyword(s), keeping receiver’s anonymity and ensuring data privacy are important features in applications like healthcare, bureaucracy, social engineering, and so on. The construction of the KeySea scheme uses the hidden access policy in attribute-based searchable encryption. The KeySea scheme provides a secure and practical solution to address the issue of privacy-preserving search over encrypted data in the public cloud storage. We show the security strengths of the KeySea scheme and its practicality with experimental results.

Efficient Anonymous Certificate-Based Multi- Message and Multi-Receiver Signcryption Scheme for Healthcare Internet of Things

Healthcare Internet of Things (IoT) is an emerging paradigm, which can provide comprehensive and different types of health services and enable various types of medical sensors to monitor patient's health conditions. In the healthcare IoT, patient is deployed with a variety of medical sensors, which continuously monitors and collects patient's sensitive health data that needs specially protection for preventing privacy leakage. To safely send multiple different health data monitored by multiple different medical sensors to multiple corresponding healthcare professionals in one data report, several multi-message and multi-receiver signcryption schemes have been introduced by employing the traditional public key cryptography, identity-based cryptography or certificateless cryptography. However, these schemes suffer from the certificate management, key escrow and key distribution problem. Besides, due to the resource-constraint property of medical sensors, they are unsuitable for healthcare IoT in terms of both performance and privacy requirements. To solve these issues, this paper introduces an efficient anonymous certificate-based multi-message and multi-receiver signcryption scheme for healthcare IoT, where the certificate-based cryptography and elliptic curve cryptography are combined to simplify the certificate management problem, eliminate the key escrow problem, solve the key distribution problem and ensure the privacy-preserving. Furthermore, the security analysis suggests that the proposed scheme is able to achieve the confidentiality, unforgeability, receiver anonymity, sender anonymity and decryption fairness; the performance evaluation indicates that the proposed scheme brings to the lower computation cost and communication cost in comparison to the existing schemes.

Efficient and Provably Secure Multireceiver Signcryption Scheme for Multicast Communication in Edge Computing

With the popularity of edge computing, edge nodes are connected with the Internet of Things (IoT) devices to process and analyze IoT-created data, and feedback corresponding results to users, devices, or data centers. In the edge computing environment, multicast is a typical communication pattern to support data transmitting between edges and devices. It allows the sender to send messages to multiple receivers in one broadcast message. To construct a secure multicast channel, the primary issue is to ensure the privacy and credibility of the transmitted message in the open wireless communication. Then, another essential issue for multicast channels is receiver anonymity, i.e., only the sender knows the receivers’ identities. Also, efficiency and provable security are critical in scheme design. In this article, we design a certificateless multimessage and multireceiver signcryption (CLMMSC) scheme by using the elliptic curve cryptography. To facilitate lightweight deployment, we adapt the certificateless mechanism to reduce the system operation and maintenance costs. Then, through security proofs, we demonstrate that the proposed scheme can achieve the expected security properties. The performance analysis shows that the proposed scheme has lower communication costs than previous CLMMSC schemes.

Efficient and Anonymous Certificateless Multi-Message and Multi-Receiver Signcryption Scheme Based on ECC

As the further extension of the multi-receiver signcryption, the multi-message and multi-receiver signcryption allows a sender to simultaneously signcrypt different messages for different receivers in only one logic operation, which makes it more flexible than the traditional multi-receiver signcryption in which only the same and unique message can be sent to all authorized receivers. The existing multi-message and multi-receiver signcryption schemes are constructed based on either the identity-based cryptography or the public key infrastructure-based cryptography, and thus, they have to suffer from the key escrow problem inherent in the identity-based cryptography or the public key certificate management burden related with the public key infrastructure-based cryptography. Certificateless public key cryptography provides an idea to solve the key escrow problem and eliminate the public key certificate management burden and has been applied to many cryptographic algorithms. In this paper, to avoid the above problems in the existing multi-message and multi-receiver signcryption schemes, the concept of the certificateless public key cryptography was introduced into the designing of the multi-message and multi-receiver signcryption, and a certificateless multi-message and multi-receiver signcryption scheme was proposed. The proposed scheme is free from the key escrow problem and the public key certificate management burden because it is constructed based on the certificateless public key cryptography. Moreover, compared with the existing schemes, it is improved in efficiency because it does not use the bilinear pairing operations but utilizes the limited number of scalar point multiplication on elliptic curve cryptography operations. At the same time, the proposed scheme achieves receiver anonymity.

Efficient Certificateless Anonymous Multi-Receiver Encryption Scheme without Bilinear Parings

With the growing development of Internet technology and popularization of mobile devices, we easily access the Internet anytime and anywhere by mobile devices. It has brought great convenience for our lives. But it brought more challenges than traditional wired communication, such as confidentiality and privacy. In order to improve security and privacy protection in using mobile network, numerous multi-receiver identity-based encryption schemes have been proposed with bilinear pairing and probabilistic hap-to-point (HTP) function. To address the troubles of private key escrow in multi-receiver encryption scheme based on ID-PKC, recently, some certificateless anonymous multi-receiver encryption (CLAMRE) schemes are introduced. But previous CLAMRE schemes using the bilinear pairing are not suitable to mobile device because the use of bilinear pairing and probabilistic hash-to-point (HTP) function results in expensive operation costs in encryption or decryption. In this paper, we propose an efficient CLAMRE scheme using elliptic curve cryptography (ECC) without bilinear pairing and HTP hash function. Since our scheme does not use bilinear pairing and HTP operation during the encryption and decryption process, the proposed CLAMRE scheme has much less computation cost than the latest CLAMRE schemes. Performance analysis shows that runtime of our scheme is much less when the sender generates ciphertext, compared with existing schemes. Security analysis shows proposed CLAMRE scheme provides confidentiality of message and receiver anonymity under the random oracle model with the difficulties of decision Diffie-Hellman problem and against the adversaries defined in CL-PKC system.

Age-based anonymity: a randomized routing approach to communication unobservability

Providing anonymous communication on networks of interconnected computers is an active area of research which aims to enhance the privacy of the users of such networks. Communication unobservability, stronger property compared to anonymity, attempts to guarantee that legitimate messages are not discernible from dummy traffic. A network with an active global adversary is one which it is assumed that all nodes in the network are potentially being monitored at all times, and also that at any time any node could be an adversary. This paper introduces a set of anonymous system design requirements for providing enhanced communication unobservability. A new anonymous networking system was designed based on these requirements to provide both sender and receiver anonymity. The proposed system has a structured peer-to-peer network architecture and a randomized routing algorithm to obfuscate the detection of communication paths and the message routing patterns. An age-based method is proposed to prevent even the first node after the sender from identifying the original sender. A simulation program was designed and implemented to test the proposed system. The effect of different parameters on the proposed algorithm is demonstrated using a simulation program.

Anonymous multi-receiver broadcast encryption scheme with strong security

Anonymity is an important way to achieve the privacy protection of identity. Recently, to protect the identities of the receivers, many anonymous multi-receiver ID-based broadcast encryption schemes have been proposed. However, most of existing schemes are shown to not be able to protect the privacy of the receivers, and their schemes are only proven to have IND-sMID-CCA security and ANON-sID-CCA security. To achieve anonymity of the receivers' identities and stronger security proof, in this paper, we first redefine the security notion of the receiver anonymity and make that the definition is stronger than the definition of previous receiver anonymity. Then we propose a novel anonymous multi-receiver ID-based broadcast encryption scheme, and show that our scheme is proven to be secure against the IND-MID-CCA attacks and ANON-ID-CCA attacks in the random oracle model, our security model is stronger than the selective identity attack model on which most of existing schemes are based. Finally, we analyse the performance of our scheme by comparing with four other schemes, the result shows that our scheme is the most efficient one.

A Novel Multi-Receiver Signcryption Scheme with Complete Anonymity.

Anonymity, which is more and more important to multi-receiver schemes, has been taken into consideration by many researchers recently. To protect the receiver anonymity, in 2010, the first multi-receiver scheme based on the Lagrange interpolating polynomial was proposed. To ensure the sender’s anonymity, the concept of the ring signature was proposed in 2005, but afterwards, this scheme was proven to has some weakness and at the same time, a completely anonymous multi-receiver signcryption scheme is proposed. In this completely anonymous scheme, the sender anonymity is achieved by improving the ring signature, and the receiver anonymity is achieved by also using the Lagrange interpolating polynomial. Unfortunately, the Lagrange interpolation method was proven a failure to protect the anonymity of receivers, because each authorized receiver could judge whether anyone else is authorized or not. Therefore, the completely anonymous multi-receiver signcryption mentioned above can only protect the sender anonymity. In this paper, we propose a new completely anonymous multi-receiver signcryption scheme with a new polynomial technology used to replace the Lagrange interpolating polynomial, which can mix the identity information of receivers to save it as a ciphertext element and prevent the authorized receivers from verifying others. With the receiver anonymity, the proposed scheme also owns the anonymity of the sender at the same time. Meanwhile, the decryption fairness and public verification are also provided.