Threshold Cryptography Research Articles

Secured Approach to Routing in Mobile Ad Hoc Networks

The main objective is to put an effort to improve security in routing protocols, especially Clustered routing Protocol using concepts of Threshold Cryptography of distributed key management and certification. Today, networks security, whatever they are wireless or not, is an important component in the network management. The works done and studied so far are limited either up to one hop networks or for application layer services only. This work thus has been proposed to implement threshold cryptography over Clustered Based Routing Protocol. This work thus has been proposed to implement threshold cryptography over Clustered Based Routing Protocol and to study its behavior of packet flow on the basis of average packet delay in which key size is compared versus number of shareholders.

An Efficient Certificateless Threshold Decryption Schemes Based On Pairings

As the combination of certificateless encryption and threshold cryptography, the certificateless threshold decryption (CLTD) scheme can avoid both the single point of failure in the distributed networks and the inherent key escrow problem in identity-based cryptosystem. This paper presents a CLTD schemes from pairings. We use the Shamir secret sharing method to indirectly split the private keys in the group G into the shares in the finite field Zq. Our CLTD scheme succeed in involving much less pairing computation for generating or verifying decryption shares. The decryption share supports short length, fast generation and batch verification. Sharing the private key is completed by its holder himself without needing help from KGC. The security proof is provided in the random oracle model.

An Improved Protocol for Proxy Based Certification Authority for MANETs

This paper includes developing framework for proxy based certificate Authority for MANET. Key management is a central aspect for security in mobile ad hoc networks. In mobile ad hoc networks, the computational load and complexity for key management is strongly subject to restriction of the node’s available resources and the dynamic nature of the topology. PKI has been recognized as one of the most effective tools for providing security for dynamic networks. However, providing such an infrastructure in MANETs is a challenging task due to their infrastructure-less nature. In this paper we have considered such challenges in detail, identify the requirements for such solutions, and propose a practical PKI service for MANETs. We used threshold cryptography to distribute the CA functionality. To reduce the overhead research work employs a proxy and a timer during multicasting to achieve certification service. Results from simulation establish the effectiveness and the efficiency of the approach.

CellTCS:A Secure Threshold Cryptography Scheme based on Non-linear Hybrid Cellular Automata

This paper presents a secure threshold cryptography scheme, referred here as CellTCS, designed based on the features of non–linear hybrid Cellular Automata. CellTCS generates the secrets to be shared among m number of entities based on a simple logic structure, however, to learn information about the original secret from k or less shares is an extremely difficult task. CellTCS is effective in terms of efficiency, scalability and correctness.

Zero-Knowledge Argument for Simultaneous Discrete Logarithms

In Crypto 1992, Chaum and Pedersen introduced a protocol (CP protocol for short) for proving the equality of two discrete logarithms (EQDL) with unconditional soundness, which is widely used nowadays and plays a central role in DL-based cryptography. Somewhat surprisingly, the CP protocol has never been improved for nearly two decades since its advent. We note that the CP protocol is usually used as a non-interactive proof by using the Fiat-Shamir heuristic, which inevitably relies on the random oracle model (ROM) and assumes that the adversary is computationally bounded. In this paper, we present an EQDL protocol in the ROM which saves approximately 40% of the computational cost and approximately 33% of the prover’s outgoing message size when instantiated with the same security parameter. The catch is that our security guarantee only holds for computationally bounded adversaries. Our idea can be naturally extended for simultaneously showing the equality of n discrete logarithms with O(1)-size commitment, in contrast to the n-element adaption of the CP protocol which requires O(n)-size. This improvement benefits a variety of interesting cryptosystems, ranging from signatures and anonymous credential systems, to verifiable secret sharing and threshold cryptosystems. As an example, we present a signature scheme that only takes one (offline) exponentiation to sign, without utilizing pairing, relying on the standard decisional Diffie-Hellman assumption.

Decentralized certification scheme for secure admission in on-the-fly peer-to-peer systems

Several alternative schemes have been presented in the literature to try to solve the users’ admission problem in P2P systems when it is not possible to include a logically centralized authority (either online or offline) in the system. However, most of them are not suitable for on-the-fly P2P systems and the most typical ones (IP based, shared secret and threshold cryptography) have several security and performance drawbacks. From the deficiencies of the existing schemes, in this paper we present a new decentralized certification scheme for on-the-fly P2P systems which is based on the recently published Internet Attribute Certificate Profile for Authorization. Our proposal greatly improves the security and flexibility of IP based and shared secret schemes with no infrastructure cost and with a minimal performance charge. Also, it achieves a similar level of security than threshold cryptography while highly reducing its computational and communicational cost. All these facts position our certification proposal as a users’ admission alternative for on-the-fly P2P systems in non very hostile environments where performance and security are key factors.

Chord-PKI: A distributed trust infrastructure based on P2P networks

Many P2P applications require security services such as privacy, anonymity, authentication, and non-repudiation. Such services could be provided through a hierarchical Public Key Infrastructure. However, P2P networks are usually Internet-scale distributed systems comprised of nodes with an undetermined trust level, thus making hierarchical solutions unrealistic. In this paper, we propose Chord-PKI, a distributed PKI architecture which is build upon the Chord overlay network, in order to provide security services for P2P applications. Our solution distributes the functionality of a PKI across the peers by using threshold cryptography and proactive updating. We analyze the security of the proposed infrastructure and through simulations we evaluate its performance for various scenarios of untrusted node distributions.

An efficient anycast scheme for discovering k services in cluster‐based mobile ad hoc networks

AbstractAnycast is a one‐to‐any bidirectional transmission scheme that can be used to provide various service‐oriented applications. However, traditional anycast cannot support some distributed applications that need to locate multiple servers such as network time protocols and threshold cryptography. Although there are some extended anycast schemes that can support the discovery of k services, they may cause high control overhead, low satisfaction ratio, or high searching latency when there are more service requesters and providers. The main reasons for these shortcomings are unknown service information and limited hierarchical structure. This work proposes an efficient anycast scheme, called AnyKast, for discovering k services in cluster‐based mobile ad hoc networks. In the AnyKast scheme, an anycast tree based on the clustering and virtual backbone is established to reduce unnecessary message transmission. In the anycast tree, anycast clusterheads disseminate their information to certain specific nodes that take the service information and perform the service selection task instead of blindly searching. Furthermore, to decrease the cost of service information collection and maintenance, scope flooding is used to limit the information transmission, and information piggybacking and periodical inquiry mechanism are used to increase the service information accuracy. The experimental results demonstrate that our scheme can effectively discover services, reduce request and reply message control overhead, and lower the searching latency. Copyright © 2010 John Wiley & Sons, Ltd.

Secure and Robust IPV6 Autoconfiguration Protocol For Mobile Adhoc Networks Under Strong Adversarial Model

Automatic IP address assignment in Mobile Ad hoc Networks (MANETs) enables nodes to obtain routable addresses without any infrastructure. Different protocols have been developed throughout the last years to achieve this service. However, research primarily focused on correctness, efficiency and scalability; much less attention has been given to the security issues. The lack of security in the design of such protocols opens the possibility of many real threats leading to serious attacks in potentially hostile environments. Recently, few schemes have been proposed to solve this problem, but none of them has brought satisfactory solutions. Auto-configuration security issues are still an open problem. In this paper, a robust and secure stateful IP address allocation protocol for standalone MANETs is specified and evaluated within NS2. Our solution is based on mutual authentication, and a fully distributed Autoconfiguration and CA model, in conjunction with threshold cryptography. By deploying a new concept of joint IP address and public key certificate, we show that, instead of earlier approaches, our solution solves the problem of all possible attacks associated with dynamic IP address assignment in MANETs. The resulting protocol incurs low latency and control overhead.

"Discrete Logarithm based 't, n' Threshold Group Signature Scheme"

of the Internet has boosted electronic information exchange on both the personal and business levels. There is a need of the authentication of messages sent by a group of individuals to another group. A (t, n) threshold group signature scheme is a method for allowing a member of a group to anonymously sign a message on behalf of the group. The idea of threshold cryptography is to protect information by distributing it among a cooperating member. Following some ideas of the classical threshold signature scheme, a (t, n) threshold group signature scheme and (k, m) threshold group signature verification scheme based on discrete logarithm problem is proposed. The group signature is generated by at least t group members and is verified by at least k members in the group. Only one group public key is required. Each group member separately signs the message. The scheme is highly secure and resists the conspiracy attack.

Access control using threshold cryptography for ubiquitous computing environments

Ubiquitous computing is revolutionizing the way humans interact with machines and carry out everyday tasks. It extends everyday computing into the physical world, creating computationally smart environments that feature seamless interactions and automation. As a result of the highly distributed nature of ubiquitous computing, it is essential to develop security mechanisms that lend themselves well to the delicate properties of smart ubiquitous computing environments. In this paper, we introduce a context-aware access control mechanism that utilizes threshold cryptography and multilayer encryption to provide a dynamic and truly distributed method for access control. We simulate our access control scheme and show that access control decisions can be made in a timely manner even as we increase key and file sizes. This mechanism is closely coupled with the context-capturing services and security policy service resulting in a fully context-aware and seamless access control mechanism for typical ubiquitous computing scenarios.

Exploiting Trust-Based Social Networks for Distributed Protection of Sensitive Data

How can we protect sensitive data of average users? In this paper, we propose taking advantage of real-life social trust between average users (called “trust-based social networks”) as well as threshold cryptography. This leads to a new type of complex systems, for which we define and characterize the following novel properties: 1) attack-resilience, which captures the consequences of computers getting compromised; 2) security utility of anonymous social networks, which captures the security gained when the underlying social network links are not known to the attacker; 3) security utility of psychological soundness, which captures the security gained when a user keeps a decisive share of its sensitive data; 4) availability, which captures the effect when computers are not always responsive; 5) the trade-off between attack-resilience and availability.

A Distributed Public Key Infrastructure Based on Threshold Cryptography for the HiiMap Next Generation Internet Architecture

In this article, a security extension for the HiiMap Next Generation Internet Architecture is presented. We regard a public key infrastructure which is integrated into the mapping infrastructure of the locator/identifier-split addressing scheme. The security approach is based on Threshold Cryptography which enables a sharing of keys among the mapping servers. Hence, a more trustworthy and fair approach for a Next Generation Internet Architecture as compared to the state of the art approach is fostered. Additionally, we give an evaluation based on IETF AAA recommendations for security-related systems.

SCCR: a generic approach to simultaneously achieve CCA security and collusion‐resistance in proxy re‐encryption

AbstractBy allowing a proxy to blindly perform meaningful transformations from one ciphertext to another, proxy re‐encryption (PRE) is an important cryptographic primitive in many applications, such as encrypted email forwarding and distributed file system. Due to its usefulness, various PRE schemes have been proposed; however, only one can simultaneously achieve chosen ciphertext security (CCA security) and collusion‐resistance. When such schemes are deployed, lack of CCA security will cause secret leaking, and lack of collusion‐resistance will cause non‐repudiation damage. In this paper, we propose a novel approach (denoted SCCR) to simultaneously achieve CCA security and collusion‐resistance in PRE, which faces daunting new challenges. We address these challenges by using CCA‐secure (2, 2) threshold cryptosystem to obtain public verifiability, and the method of key management in identity‐based encryption (IBE) to achieve collusion‐resistance. These two novel techniques have not been yet used in any previous PRE schemes. A unique characteristic of SCCR is that it is a generic construction which has more advantages than a concrete PRE scheme does. Copyright © 2009 John Wiley & Sons, Ltd.

Towards providing a new lightweight authentication and encryption scheme for MANET

Mobile Ad hoc Network (MANET) is a wireless technology for mobile nodes. This network is setup on fly without any infrastructure. The mobility nature of this network and the lack of infrastructure make it very challenging to be secured. In this paper, we introduce a formal model for Identity-based RSA (Id-RSA) scheme proven secure in the random oracle model. The proposed scheme relies on establishing fast cryptography operations to enhance the network performance. We compare our scheme with RSA-based Threshold Cryptography scheme (RSA-TC) and ECC-based Threshold Cryptography scheme (ECC-TC) in terms of speed and overheads caused by the security messages. We show that the threshold cryptography operations involved in RSA-TC and ECC-TC schemes cause a lot of overheads and delay. We implement these three schemes using the JAVA-based simulation framework (JIST/SWANS). The results show that our Id-RSA scheme is more suitable for MANET mobility environment that require lightweight and secure solutions.

Secure and robust threshold key management (SRKM) scheme for ad hoc networks

AbstractSecuring Mobile ad hoc Networks (MANET) is a challenging task, notably due to the lack of an online infrastructure. In particular, key management in MANET is a problem for which many solutions have been proposed in literature. Unfortunately, these solutions are rather limited in terms of security and availability of keys. In this paper, we propose a secure, robust, and fully distributed scheme for public‐key certificate management in MANET. Our scheme, based on threshold cryptography, ensures that the private key of the certificate authority will not be revealed to an adversary, even if the number of compromised shareholders exceeds the threshold of vulnerability, thereby thwarting mobile‐adversary attacks. We describe SRKM in detail and, by using security analysis and simulations, show its effectiveness, robustness and security. Copyright © 2010 John Wiley & Sons, Ltd.

An Efficient Certification Scheme for Nodes in a Wireless Ad Hoc Network

The attractiveness of the wireless ad hoc networks lies in the fact that these networks are selforganized: the hosts constituting the networks can communicate with each other without reliance on any centralized or specified entities such as base stations or access points. With these networks finding more applications, the need for adequate security mechanism is increasingly becoming important. Key management is an essential cryptographic primitive upon which other security protocols are built. However, most of the existing key management schemes are not feasible in ad hoc networks because public key infrastructures with a centralized certification authority are hard to deploy there. In this paper, we propose and evaluate a security mechanism based on distributed certification authority based on threshold cryptography that is suited to wireless ad hoc networks. A collection of nodes acts as the certificate authority and provides the certification service.

Securing Cluster-Based Ad Hoc Networks with Distributed Authorities

In this paper, we address key management in cluster-based mobile ad hoc networks (MANETs). Ensuring secure communication in an ad hoc network is extremely challenging because of the dynamic nature of the network and the lack of centralized management. For this reason, key management is particularly difficult to implement in such networks. We present a fully-distributed ID-based multiple secrets key management scheme (IMKM). This scheme is implemented via a combination of ID-based multiple secrets and threshold cryptography. It eliminates the need for certificate-based authenticated public-key distribution and provides an efficient mechanism for key update and key revocation schemes, which leads to more suitable, economic, adaptable, scalable, and autonomous key management for mobile ad hoc networks.

Adaptively Secure Identity-Based Threshold Broadcast Encryption without Random Oracles

A mobile ad hoc network has the computational and energy constraints, the general threshold cryptography does not suit it. In this paper, we consider a new kind of proper public encryption to the ad hoc networks: threshold broadcast encryption. A new construction of identity-based threshold broadcast encryption is proposed. In the proposed scheme, any user can dynamically join the system as a possible recipient, and the sender can dynamically choose the set of recipients and the threshold value t. Our new scheme achieves constant size private keys and O(n-t)-size ciphertexts. This is the first scheme which achieves short ciphertexts and full security in the standard model. Finally, we also show that it is provable security under n+1-Weak Decision Bilinear Diffie-Hellman Exponent (n+1-wDBDHE) assumption.

A Context-aware Access Control Model for Pervasive Environments

Pervasive environments are dynamically changing environments with enormous amounts of information available for access from anywhere. This paper presents a framework for context-aware access control using threshold cryptography (CAAC-TC) where the administration of access control is distributed between different context services. CAAC-TC encrypts information using threshold cryptography where the private key is split up between the different context conditions which must be captured or realized. The idea here is that not all specified context conditions must be captured, and k captured contexts are enough. The management of access decisions is distributed among the different contexts. In CAAC-TC, multiple encryption layers can be specified where each layer is an encryption scheme of either n-out-of-n or k-out-of-n. Multiple layers simulate the use of an “AND" operator. Some of the main characteristics of CAAC-TC are decentralization, context error tolerance (distributed trust), extensibility, flexibility, and scalability.