Key Hierarchy Research Articles

A survey on optimization-based approaches to Dynamic Centralized Group Key management

Abstract—In secure multicast communication, only authorized group members are able to receive the transmitted data. Key generation, distribution, and management are all carried out by a single entity (called the Key Server) in the centralized system. The main challenges of a dynamic centralized group key management scheme include scalability overhead, rekeying overhead, storage overhead, maintaining forward and backward secrecy, etc. Logical Key Hierarchy (LKH), one of the key management methods, uses a tree structure to manage keys to share with participants. Due to the fact that members may join or exit the group at any time during communication, a crucial problem in centralized group key management (CGKM) is minimizing rekeying costs while maintaining a balanced tree. The majority of CGKM methods effectively update the group key by modifying cryptographic techniques or based on logical/heuristic arguments. One of the efficient approaches is based on an optimization model with the two mentioned important objectives. In this paper, we conduct a survey on optimization-based approaches to dynamic CGKM, which can be divided into two categories based on logical/heuristic arguments and a rigorous mathematical optimization model.

Integrated IoT-Based Secure and Efficient Key Management Framework Using Hashgraphs for Autonomous Vehicles to Ensure Road Safety.

Autonomous vehicles offer various advantages to both vehicle owners and automobile companies. However, despite the advantages, there are various risks associated with these vehicles. These vehicles interact with each other by forming a vehicular network, also known as VANET, in a centralized manner. This centralized network is vulnerable to cyber-attacks which can cause data loss, resulting in road accidents. Thus, to prevent the vehicular network from being attacked and to prevent the privacy of the data, key management is used. However, key management alone over a centralized network is not effective in ensuring data integrity in a vehicular network. To resolve this issue, various studies have introduced a blockchain-based approach and enabled key management over a decentralized network. This technique is also found effective in ensuring the privacy of all the stakeholders involved in a vehicular network. Furthermore, a blockchain-based key management system can also help in storing a large amount of data over a distributed network, which can encourage a faster exchange of information between vehicles in a network. However, there are certain limitations of blockchain technology that may affect the efficient working of autonomous vehicles. Most of the existing blockchain-based systems are implemented over Ethereum or Bitcoin. The transaction-processing capability of these blockchains is in the range of 5 to 20 transactions per second, whereas hashgraphs are capable of processing thousands of transactions per second as the data are processed exponentially. Furthermore, a hashgraph prevents the user from altering the order of the transactions being processed, and they do not need high computational powers to operate, which may help in reducing the overall cost of the system. Due to the advantages offered by a hashgraph, an advanced key management framework based on a hashgraph for secure communication between the vehicles is suggested in this paper. The framework is developed using the concept of Leaving of Vehicles based on a Logical Key Hierarchy (LKH) and Batch Rekeying. The system is tested and compared with other closely related systems on the basis of the transaction compilation time and change in traffic rates.

Cluster space key management scheme based on threshold secret sharing and bilinear pairing

SummarySpace key management schemes play a critical role in space information network security services. However, the existing space key management schemes are inefficient. To overcome these problems, this paper proposed a cluster group key management scheme, in which the space nodes are divided into different clusters. The ground control center (GCC) is used as a private key generation center. The threshold technique based on low‐density parity‐check code (LDPC) is used in the group key management of the cluster‐heads. The key escrow is transferred to GCC, which is a compromise of efficiency and security. The logical key hierarchy is used to manage the group key of the cluster. Furthermore, the bilinear paring‐based cryptosystem is employed to provide the identification. The formalized security proof of the protocol using the Extended Canetti–Krawczyk (ECK) model is introduced to prove the authentication and security. The consistency, forward secrecy, backward secrecy, ability to against the collusion attack and performance are analyzed and simulated. The result shows that the proposed scheme takes lower storage cost and computational cost.

A Hierarchical Multicast Key Distribution Protocol

In secure group communication, group keys (GK) are used to ensure the confidentiality of communication. The group key distribution (GKD) is responsible for updating and distributing new group keys when the group membership changes. Most well-known GKD protocols are based on a logical key hierarchy (LKH), where only one group controller (GC) is used. These protocols have various issues, including a single point of failure, meaning that the GC often has a huge workload and can be easily overwhelmed. In this paper, we propose a hierarchical multicast key distribution protocol that supports multi-level controllers to manage a group. Each controller just needs to manage the next-level nodes, and if one fails, the superior controller can replace it with minimal work. The proposed protocol effectively balances the work of controllers, greatly improves the reliability of the group key distribution, and also allows group members to build dynamic conferences without controllers. We provide a security proof of the proposed protocol in a symbolic security model and compare it to other protocols in terms of efficiency, functionality, and security.

A New Technique to Eliminate Excessive Copies of Cloud Data through Secure Key Hierarchy

A New Technique to Eliminate Excessive Copies of Cloud Data through Secure Key Hierarchy

Semi-quantum key distribution protocol based on the hyperentanglement Bell state of polarization-spatial mode

The semi-quantum key distribution protocol based on the hyperentanglement Bell state of polarization-spatial mode is presented in this paper. This protocol is utilized to share the session keys and construct key hierarchy of security systems in high capacity between the legitimate users securely. Different from the previous protocols, two quantum non-demolition detectors are constructed with cross-Kerr nonlinearities and different phase shifts for distinguishing the Bell states in spatial mode degree of freedom. Meanwhile, this protocol can improve the capacity and efficiency when the legitimate users share the session keys. And the technology of the hyperentanglement purification and hyperentanglement concentration can enhance the robustness and stability of this protocol. At last, this protocol proposed in this paper can withstand several kinds of attacks.

Analysis of Tree Structure for Secure Group Communication Using LKH Approach

In secure Group communication for applications such as pay per view, teleconferencing, and video conferencing, key management method with logarithmic computation, storage time and bandwidth efficiency are expected. Major aspects with key management are initializing the group with a group key and rekeying the group. The server maintains a key tree. Rekeying is mandatory due to dynamic group nature (join/leave operations) or periodic rekeying. Logical Key Hierarchy has a logarithmic rekeying cost if the key tree is balanced, over multiple rekeying operations key tree is not balanced and LKH yields worst Rekeying cost. To achieve logarithmic cost either keep the key tree balanced or restructure the key tree in such a way that it will still result in the best rekeying cost. This paper explores tree structures using the Logical Key Hierarchy (LKH) approach to find an optimal tree structure for an application.

RETRACTED ARTICLE: Efficient data sensing with group key management for intelligent automation system by one-way key derivation in wireless networks

Over the last century, Wireless Sensor Network (WSN) has given major advances in several distinguishable fields. In addition, it has also evolved many features such as high device heterogeneity, high scale and supporting multiple applications. In WSN, Key management is employed (involves) as a significant component of network security, especially in multi-cast based applications and services. Group key management has a vital role in multi-cast secure communication with huge number of group members. Group key must always be updated dynamically to all groups in the network and keys to be redistributed currently to active members only. Consequently, a secret key called session key for a group of members is stored in key trees that are shared efficiently between them, in order to achieve secure group communication. The key trees are used to encrypt with other keys and data are transmitted to ensure security. Logical key hierarchy (LKH) is a hierarchical structure of multiple keys to provide a scalable and secrecy for group communication. This research work proposes a new hierarchical group key management (HGKM) using multiple logical key trees for dynamic groups in order to enhance the Quality of Service of the network. Among the multiple logical trees, primary tree can be selected by tree selection algorithm. In WSN, there are high numbers of members joining or leaving the group at any time, resulting with rekeying process becoming too large. This leads to degraded efficiency of tree-based key management system. Further, communication overhead of rekeying process can be mitigated by one-way key derivation method which integrates with multiple logical key trees. In this method, tree server does not need to be encrypted. Rather, it involves in sending a new key to members who are capable of derive their own keys in same way the server does. This results with a need for less number of encrypted keys for each rekeying process within the group tree. The fixed interval time is called batch time, which is applied in each rekeying process after nodes join or leave the group. The proposed approach can improve the bandwidth utilization effectively. The proposed HGKM method is implemented in Network Simulator (NS-2) environment and obtained results are compared with existing two methods such as LKH and multiple logical tree key management (MLT-KM). QOS of proposed approach is evaluated in terms of Bandwidth Efficiency.

Analysis of influence factors in communication and collaboration between controllers and commanders

To cope with the smooth implementation of apron control transfer at Chinese airports, two new departments were established, namely apron tower and airport operation command center. Therefore, based on interview texts of controllers and commanders of these two departments, this paper uses text mining and Decision-making Trial and Evaluation Laboratory-Interpretative Structural Modeling Method methods to determine key influence factors and factor hierarchy that affect communication and collaboration in their daily work. The results show that for controllers, key influence factors are mainly personnel development and professional abilities. These factors are located at the bottom of the factor hierarchy and are the basis for ensuring smooth communication and collaboration. For commanders, key influence factors are mainly personnel professional abilities and flight status. These factors are at the top of the factor hierarchy and are focus points that affect communication and collaboration. Hence, the case analysis results show the application potential of these three methods in the field of civil aviation. The combined use of these three methods can enable airport managers to clearly understand the degree of influence between factors.

A Logical Key Hierarchy Based Approach to Preserve Content Privacy in Decentralized Online Social Networks

Distributed Online Social Networks (DOSNs) have been proposed to shift the control over user data from a unique entity, the online social network provider, to the users of the DOSN themselves. In this paper we focus on the problem of preserving the privacy of the contents shared to large groups of users. In general, content privacy is enforced by encrypting the content, having only authorized parties being able to decrypt it. When efficiency has to be taken into account, new solutions have to be devised that: i) minimize the re-encryption of the contents published in a group when the composition of the group changes; and, ii) enable a fast distribution of the cryptographic keys to all the members ( $n$ n ) of a group, each time a set of users is removed from or added to the group by the group owner. Current solutions fall short in meeting the above criteria, while our approach requires only $O(d\cdot log_d (n))$ O ( d · l o g d ( n ) ) encryption operations when a user is removed from a group (where $d$ d is an input parameter of the system), and $O(2\cdot log_d (n))$ O ( 2 · l o g d ( n ) ) when a user joins the group. The effectiveness of our approach is evaluated through simulations based on a real online social network.

A Group Key Management Scheme for WSN Based on Lagrange Interpolation Polynomial Characteristic

According to the main group key management schemes logical key hierarchy (LKH), exclusion basis systems (EBS) and other group key schemes are limited in network structure, collusion attack, high energy consumption, and the single point of failure, this paper presents a group key management scheme for wireless sensor networks based on Lagrange interpolation polynomial characteristic (AGKMS). That Chinese remainder theorem is turned into a Lagrange interpolation polynomial based on the function property of Chinese remainder theorem firstly. And then the base station (BS) generates a Lagrange interpolation polynomial function f(x) and turns it to be a mix-function f(x)’ based on the key information m(i) of node i. In the end, node i can obtain the group key K by receiving the message f(m(i))’ from the cluster head node j. The analysis results of safety performance show that AGKMS has good network security, key independence, anti-capture, low storage cost, low computation cost, and good scalability.

Key Resources in Game Developers’ Business Models

This paper presents the results of the research on key resources exploited under business models of video game developers. The main attention is paid to the identification and hierarchizing of key resources, as well as their specific types. It should be noticed that the reported study takes into account diversification of video game developers in terms of monetization models exploited, i.e. premium, freemium, or hybrid, which seems to be novel.In general, the findings locate people together with their tacit, experience-based knowledge at the top of the key resources hierarchy. Nevertheless, the results show that there are differences in perception and exploitation of the key resources among the considered types of game developers. Interestingly, only those with the premium monetization model point at tacit organizational knowledge as a specific type of key resources exploited under their business model. Moreover, the identified relational resources – although not considered in the business model canvas approach – are acknowledged only by developers using the hybrid monetization model. Last but not least, physical resources are seen as non-key ones by all the considered types of game developers.

A Computation-Efficient Group Key Distribution Protocol Based on a New Secret Sharing Scheme

With the development of 5G and the Internet of Things (IoT), mobile terminals are widely used in various applications under multicast scenarios. However, due to the limited computation resources of mobile terminals, reducing the computation cost of members in group key distribution processes of dynamic groups has become an important issue. In this paper, we propose a computation-efficient group key distribution (CEGKD) protocol. First, an improved secret sharing scheme is proposed to construct faster encryption and decryption algorithms. Second, the tree structure of logical key hierarchy (LKH) is employed to implement a simple and effective key-numbering method. Theoretical analysis is given to prove that the proposed protocol meets forward security and backward security. In addition, the experiment results show that the computation cost of CEGKD on the member side is reduced by more than 85% compared with that of the LKH scheme.

Attribute-Based Collusion Resistance in Group-Based Cloud Data Sharing using LKH Model

Utilizing cloud computing, users can avail a compelling and effective approach for information sharing between collective individuals in the cloud with the facility of less administration cost and little maintenance. Security in cloud computing refers to procedures, standards and processes created to provide assurance for security of information in the cloud environment. In this paper, we project a secure data sharing method in cloud for dynamic members by producing keys for users using Logic Key Hierarchy (LKH) model, i.e., a tree-based key generation technique. We have generated this key using reverse hashing and one way hash-based technique so that no exiled user can predict the new key and new users cannot predict the old keys of the network group. From numerous experiments, this work is proved to be the best in maintaining forward secrecy, backward secrecy and group compromise attacks and consumes less computation cost compared to any other hash-based key generation techniques.

Comprehensive evaluation of key management hierarchies for outsourced data

Key management is an essential component of a cryptographic access control system with a large number of resources. It manages the secret keys assigned to the system entities in such a way that only authorized users can access a resource. Read access control allows read access of a resource by the authorized users and disallows others. An important objective of a key management is to reduce the secret key storage with each authorized user. To this end, there exist two prominent types of key management hierarchy with single key storage per user used for read access control in data outsourcing scenario: user-based and resource-based. In this work, we analyze the two types of hierarchy with respect to static hierarchy characteristics and dynamic operations such as adding or revoking user authorization. Our analysis shows that the resource-based hierarchies can be a better candidate which is not given equal emphasis in the literature. A new heuristic for minimizing the key management hierarchy is introduced that makes it practical in use even for a large number of users and resources. The performance evaluation of dynamic operations such as adding or revoking a user’s read subscription is shown experimentally to support our analytical results.

Hierarchical group key management for secure data sharing in a cloud‐based environment

SummaryIn cloud environment, the importance of security for the outsourced data has increased much, since the data is maintained and controlled by the semi‐trusted third‐party cloud providers. Data Security is one of the major factors to be considered in group data sharing. Using the secret key, the entire file is encrypted directly in a conventional security framework; however, in a cloud‐based environment for group mechanism, this framework cannot be applied as there is a problem of key distribution. This research paper proposes an efficient hierarchical‐based group key mechanism for a cloud‐based environment. This proposed system relies on Key Distribution Server (KDS), which performs cryptographic key operations for securing the data in the cloud. Also, this system uses logical key hierarchy (LKH) protocol to maintain hierarchical tree for scalability. The group key is generated using the group member secret values and a secret value assigned by the KDS server. Performance analysis of this system shows that the proposed key management system is more efficient and much suitable for cloud environment.

PHE: An Efficient Traitor Tracing and Revocation for Encrypted File Syncing-and-Sharing in Cloud

Recently, many enterprises have moved their data into the cloud by using file syncing and sharing (FSS) services, which have been deployed for mobile users. However, Bring-Your-Own-Device (BYOD) solutions for increasingly deployed mobile devices have also in fact raised a new challenge for how to prevent users from abusing the FSS service. In this paper, we address this issue by using a new system model involving anomaly detection, tracing, and revocation approaches. The presented solution applies a new threshold public key based cryptosystem, called partially-ordered hierarchical encryption (PHE), which implements a partial-order key hierarchy and it is similar to role hierarchy widely used in RBAC. PHE provides two main security mechanisms, i.e., traitor tracing and key revocation, which can greatly improve the efficiency compared to previous approaches. The security and performance analysis shows that PHE is a provably secure threshold encryption and provides following salient management and performance benefits: it can promise to efficiently trace all possible traitor coalitions and support public revocation not only for the users but for the specified groups.

A Console GRID Leveraged Authentication and Key Agreement Mechanism for LTE/SAE

The growing popularity of multimedia applications, pervasive connectivity, higher bandwidth, and euphoric technology penetration among the bulk of the human race that happens to be cellular technology users, has fueled the adaptation to Long Term Evolution (LTE)/ System Architecture Evolution (SAE). The LTE fulfills the resource demands of the next generation applications for now. We identify security issues in the authentication mechanism used in LTE that without countermeasures might give superuser rights to unauthorized users. The LTE uses static LTE Key (LTE-K) to derive the entire key hierarchy such as LTE follows Evolved Packet System-Authentication and Key Agreement (EPS-AKA) based authentication which discloses user identity, location, and other Personally Identifiable Information (PII). To counter this, we propose a public key cryptosystem named International mobile subscriber identity Protected Console Grid-based Authentication and Key Agreement (IPG-AKA) protocol to address the vulnerabilities related to weak key management. From the data obtained from threat modeling and simulation results, we claim that the IPG-AKA scheme not only improves the security of authentication procedures, it also shows improvements in authentication loads and reduction in key generation time. The empirical results and qualitative analysis presented in this paper proves that IPG-AKA improves security in authentication procedure and performance in the LTE.

Mobile agent based secure internet business using access key hierarchy management scheme

To access the distributed web applications in a computer network, mobile agents have long been proved to be a successful tool. The power of a mobile agent lies in migrating to the destination hosts directly for retrieving the information under consideration. Since many businesses run their sensitive data in distributed servers, it has been a mandatory demand that before the information is downloaded, the mobile agents need to be authenticated and authorized. To provide such authentication, digital signatures based on well known algorithms such as RSA, ECC have been proposed in the past. The main drawback of these works is that the they are not computationally efficient during the encryption and decryption of keys which are used to encrypt and decrypt the content. Thus, the major contribution of our work is to reduce the computational complexity for the authentication of mobile agents through a new hierarchical access management scheme. The computational costs are reduced during the key derivation and signature verification processes. The proposed work not only reduces the computational time, but provides flexibility to give fine grained access to the mobile agents to access only the authorized files. Extensive simulations prove that our approach significantly reduces the computational overhead than the recent works in the literature and hence this approach is best suited for implementation in the distributed web environments.

An efficient protocol for secure multicast key distribution in the presence of adaptive adversaries

In this paper, an efficient construction of multicast key distribution schemes based on semantically secure symmetric-key encryption schemes and cryptographically strong pseudo-random number generators is presented and analyzed. The proposed scheme is provably secure against adaptive adversaries leveraging the security amplification technique defined over the logical key hierarchy structures. Our protocol tolerates any coalition of revoked users; in particular, we do not assume any limit on the size or structure of the coalition. The proposed scheme is efficient as a performance of Join or Leave procedure requires $2 \log(N)$ multicast activities defined over a sibling ancestor node set, $2 \log(N)$ internal state updates of the underlying pseudo-random number generator and $2\log(N)$ symmetric-key encryption activities for $N$ users in a session.