Biblio

Vehicular Social Networks (VSNs) are expected to become a reality soon, where commuters having common interests in the virtual community of vehicles, drivers, passengers can share information, both about road conditions and their surroundings. This will improve transportation efficiency and public safety. However, social networking exposes vehicles to different kinds of cyber-attacks. This concern can be addressed through an efficient and secure key management framework. This study presents a Secure and Transparent Public-key Management (ST-PKMS) based on blockchain and notary system, but it addresses security and privacy challenges specific to VSNs. ST-PKMS significantly enhances the efficiency and trustworthiness of mutual authentication. In ST-PKMS, each vehicle has multiple short-lived anonymous public-keys, which are recorded on the blockchain platform. However, public-keys get activated only when a notary system notarizes it, and clients accept only notarized public-keys during mutual authentication. Compromised vehicles can be effectively removed from the VSNs by blocking notarization of their public-keys; thus, the need to distribute Certificate Revocation List (CRL) is eliminated in the proposed scheme. ST-PKMS ensures transparency, security, privacy, and availability, even in the face of an active adversary. The simulation and evaluation results show that the ST-PKMS meets real-time performance requirements, and it is cost-effective in terms of scalability, delay, and communication overhead.

Zigbee network security relies on symmetric cryptography based on a pre-shared secret. In the current Zigbee protocol, the network coordinator creates a network key while establishing a network. The coordinator then shares the network key securely, encrypted under the pre-shared secret, with devices joining the network to ensure the security of future communications among devices through the network key. The pre-shared secret, therefore, needs to be installed in millions or more devices prior to deployment, and thus will be inevitably leaked, enabling attackers to compromise the confidentiality and integrity of the network. To improve the security of Zigbee networks, we propose a new certificate-less Zigbee joining protocol that leverages low-cost public-key primitives. The new protocol has two components. The first is to integrate Elliptic Curve Diffie-Hellman key exchange into the existing association request/response messages, and to use this key both for link-to-link communication and for encryption of the network key to enhance privacy of user devices. The second is to improve the security of the installation code, a new joining method introduced in Zigbee 3.0 for enhanced security, by using public key encryption. We analyze the security of our proposed protocol using the formal verification methods provided by ProVerif, and evaluate the efficiency and effectiveness of our solution with a prototype built with open source software and hardware stack. The new protocol does not introduce extra messages and the overhead is as lows as 3.8% on average for the join procedure.

As RFID system has fewer calculation and storage resources for RF tag, it is difficult to adopt the traditional encryption algorithm technology with higher security, which leads to the system being vulnerable to counterfeiting, tampering, leakage and other problems. To this end, a lightweight bidirectional security authentication method based on the combined public key is proposed. The method deals with the key management problem of the power Internet of things (IoT) in the terminal layer device by studying the combined public key (CPK) technology. The elliptic curve cryptosystem in the CPK has the advantages of short key length, fast calculation speed and small occupied bandwidth, which is very suitable for the hardware environment of RFID system with limited performance. It also ensures the security of the keys used in the access of the IoT terminal equipment to the authentication, and achieves overall optimization of speed, energy consumption, processing capacity and security.

The PTPv2.1 standard provides new protection mechanisms to ensure the authenticity and integrity of PTP messages. However, the distribution of the necessary security parameters is not part of the specification. This paper proposes a simple and practical approach for the automated distribution of these parameters by using a key management system that enables the Immediate Security Processing in PTP. It is based on the Network Time Security protocol and offers functions for group management, parameter updating and monitoring mechanisms. A Proof-of-Concept implementation provides initial results of the resources required for the key management system and its use.

An Identity-Based Encryption (IBE) scheme uses public identities of entities for cryptographic purposes. Unlike that, we introduce a new scheme which is based on private identities, and we call it Private Identity-Based Encryption. A Private IBE scheme makes sure the adversaries cannot get the information that somebody uses for encryption in order to decrypt the data. Moreover, thanks to using identities as secret keys, an user-friendly system can be designed to support users in protecting data without storing any keys privately. This allows builds decentralized applications to manage keys that is often long and difficult to remember.

Cloud computing can be described as a distributed design that is accessible to different forms of security intrusions. An encoding technique named homomorphic encoding is used for the encoding of entities which are utilized for the accession of data from cloud server. The main problems of homomorphic encoding scheme are key organization and key allocation. Because of these issues, effectiveness of homomorphic encryption approach decreases. The encoding procedure requires the generation of input, and for this, an approach named Particle swarm optimization is implemented in the presented research study. PSO algorithms are nature encouraged meta-heuristic algorithms. These algorithms are inhabitant reliant. In these algorithms, societal activities of birds and fishes are utilized as an encouragement for the development of a technical mechanism. Relying on the superiority of computations, the results are modified with the help of algorithms which are taken from arbitrarily allocated pattern of particles. With the movement of particles around the searching area, the spontaneity is performed by utilizing a pattern of arithmetical terminology. For the generation of permanent number key for encoding, optimized PSO approach is utilized. MATLAB program is used for the implementation of PSO relied homomorphic algorithm. The investigating outcomes depicts that this technique proves very beneficial on the requisites of resource exploitation and finishing time. PSO relied homomorphic algorithm is more applicable in terms of completion time and resource utilization in comparison with homomorphic algorithm.

In the vertical multi-level public network, the ciphertext video needs to support the distribution of key in the whole network when it is shared across different security domains horizontally. However, the traditional key management mode faces great pressure on the security classification and encryption efficiency, and especially, it cannot fully ensure the security of content and key when sharing across-domains. Based on the above analysis, this paper proposes a cross domain video security sharing solution based on white box encryption theory to improve the security of video data sharing. In this solution, the white box encryption technology is adopted to establish the data sharing background trust mechanism based on the key management center, and we study the white box key protection technology of the video terminal to support the mass level key distribution in the network and the online security generation and replacement of the white box password module, so that the safe and fast cross domain exchange and sharing of video data are realized.

A hierarchical key management scheme for mobile agents in e-medicine system enables users, such as patients, doctors, nurses and health visitors, to conveniently and securely access a remote hierarchical medical database system via public networks. Efficient hierarchical key management schemes do not require heavy computations even if the hierarchical structure has too many levels and participants. Chen et al. recently developed a hierarchical key management scheme with date-constraint for mobile agents. The key management scheme of Chen et al. is based the Elliptic Curve Cryptosystem and allows each secret key to be partnered with a validity period by using one-way hash chains. However, the scheme of Chen et al. fails to execute correctly, violates authenticated key security, and requires hundreds of hash functional operations. This investigation discusses these limitations, and proposes an efficient date-constraint hierarchical key management scheme for mobile agents in e-medicine system, which provides a fast key validation and expiration check phase to rapidly check whether the secret keys are valid and time-expired or not. The proposed key management scheme not only provides more security properties and rapidly checks the validation of secret keys, but also reduces the computational cost..

The data collected by IoT devices is of great value, which makes people urgently need a secure device key management strategy to protect their data. Existing works introduce the blockchain technology to transfer the responsibility of key management from the trusted center in the traditional key management strategy to the devices, thus eliminating the trust crisis caused by excessive dependence on third parties. However, the lightweight implementation of IoT devices limits the ability to resist side channel attacks, causing the private key to be exposed and subject to masquerading attacks. Accordingly, we strengthen the original blockchain based key management scheme to defend against key exposure attack. On the one hand, we introduce two hash functions to bind transactions in the blockchain to legitimate users. On the other hand, we design a secure key exchange protocol for identifying and exchanging access keys between legitimate users. Security analysis and performance show that the proposed scheme improves the robustness of the network with small storage and communication overhead increments.

Quantum Key Distribution (QKD) is a technique for sharing encryption keys between two adjacent nodes. It provides unconditional secure communication based on the laws of physics. From the viewpoint of network research, QKD is considered to be a component for providing secure communication in network systems. A QKD network enables each node to exchange encryption keys with arbitrary nodes. However previous research did not focus on the processing speed of the key management method essential for a QKD network. This paper focuses on the key management method assuming a high-speed QKD system for which we clarify the design, propose a high-speed method, and evaluate the throughput. The proposed method consists of four modules: (1) local key manager handling the keys generated by QKD, (2) one-time pad tunnel manager establishing the transparent encryption link, (3) global key manager generating the keys for application communication, and (4) web API providing keys to the application. The proposed method was implemented in software and evaluated by emulating QKD key generation and application key consumption. The evaluation result reveals that it is capable of handling the encryption keys at a speed of 414 Mb/s, 185 Mb/s, 85 Mb/s and 971 Mb/s, for local key manager, one-time pad tunnel manager, global key manager and web API, respectively. These are sufficient for integration with a high-speed QKD system. Furthermore, the method allows the high-speed QKD system consisting of two nodes to expand corresponding to the size of the QKD network without losing the speed advantage.

In this article, to deal with data security requirements of electric vehicle users, a key management scheme for smart charging has been studied. According to the characteristics of the network, three elements and a two-subnetwork model between the charging and the electric vehicle users have been designed. Based on the hypergraph theory, the hypergraph structure of the smart charging network is proposed. And the key management scheme SCHKM is designed to satisfy the operational and security requirements of this structure. The efficiency of SCHKM scheme is analyzed from the cost experiment of key generation and key storage. The experimental results show that compared with the LKH, OFT and GKMP, the proposed key management scheme has obvious advantages in multi-user and key generation cost.

In this paper, we focus on versatile and scalable key management for Advanced Metering Infrastructure (AMI) in Smart Grid (SG). We show that a recently proposed key graph based scheme for AMI systems (VerSAMI) suffers from efficiency flaws in its broadcast key management protocol. Then, we propose a new key management scheme (iVerSAMI) by modifying VerSAMI's key graph structure and proposing a new broadcast key update process. We analyze security and performance of the proposed broadcast key management in details to show that iVerSAMI is secure and efficient in terms of storage and communication overheads.

Email privacy is of crucial importance. Existing email encryption approaches are comprehensive but seldom used due to their complexity and inconvenience. We take a new approach to simplify email encryption and improve its usability by implementing receiver-controlled encryption: newly received messages are transparently downloaded and encrypted to a locally-generated key; the original message is then replaced. To avoid the problem of moving a single private key between devices, we implement per-device key pairs: only public keys need be synchronized via a simple verification step. Compromising an email account or server only provides access to encrypted emails. We implemented this scheme on several platforms, showing it works with PGP and S/MIME, is compatible with widely used mail clients and email services including Gmail, has acceptable overhead, and that users consider it intuitive and easy to use.

The paper considers data security issues in vehicle-to-infrastructure communications, where vehicles stream data to a road side unit. We assume aggregated data in road side units can be stored or used for data analytics. In this environment, there are issues in regards to the scalability of key management and computation limitations at the edge of the network. To address these issues, we suggest the formation of groups in the vehicle layer, where a group leader is assigned to communicate with group devices and the road side unit. We propose a lightweight permutation mechanism for preserving the confidentiality of sensory data.

Using security primitives, a novel scheme for licensing hardware intellectual properties (HWIPs) on Field Programmable Gate Arrays (FPGAs) in public clouds is proposed. The proposed scheme enforces a pay-per-use model, allows HWIP's installation only on specific on-cloud FPGAs, and efficiently protects the HWIPs from being cloned, reverse engineered, or used without the owner's authorization by any party, including a cloud insider. It also provides protection for the users' designs integrated with the HWIP on the same FPGA. This enables cloud tenants to license HWIPs in the cloud from the HWIP vendors at a relatively low price based on usage instead of paying the expensive unlimited HWIP license fee. The scheme includes a protocol for FPGA authentication, HWIP secure decryption, and usage by the clients without the need for the HWIP vendor to be involved or divulge their secret keys. A complete prototype test-bed implementation showed that the proposed scheme is very feasible with relatively low resource utilization. Experiments also showed that a HWIP could be licensed and set up in the on-cloud FPGA in 0.9s. This is 15 times faster than setting up the same HWIP from outside the cloud, which takes about 14s based on the average global Internet speed.

Physically Unclonable Functions (PUFs) promise to be a critical hardware primitive to provide unique identities to billions of connected devices in Internet of Things (IoTs). In traditional authentication protocols a user presents a set of credentials with an accompanying proof such as password or digital certificate. However, IoTs need more evolved methods as these classical techniques suffer from the pressing problems of password dependency and inability to bind access requests to the “things” from which they originate. Additionally, the protocols need to be lightweight and heterogeneous. Although PUFs seem promising to develop such mechanism, it puts forward an open problem of how to develop such mechanism without needing to store the secret challenge-response pair (CRP) explicitly at the verifier end. In this paper, we develop an authentication and key exchange protocol by combining the ideas of Identity based Encryption (IBE), PUFs and Key-ed Hash Function to show that this combination can help to do away with this requirement. The security of the protocol is proved formally under the Session Key Security and the Universal Composability Framework. A prototype of the protocol has been implemented to realize a secured video surveillance camera using a combination of an Intel Edison board, with a Digilent Nexys-4 FPGA board consisting of an Artix-7 FPGA, together serving as the IoT node. We show, though the stand-alone video camera can be subjected to man-in-the-middle attack via IP-spoofing using standard network penetration tools, the camera augmented with the proposed protocol resists such attacks and it suits aptly in an IoT infrastructure making the protocol deployable for the industry.

We present a machine-checked proof of security for the domain management protocol of Amazon Web Services' KMS (Key Management Service) a critical security service used throughout AWS and by AWS customers. Domain management is at the core of AWS KMS; it governs the top-level keys that anchor the security of encryption services at AWS. We show that the protocol securely implements an ideal distributed encryption mechanism under standard cryptographic assumptions. The proof is machine-checked in the EasyCrypt proof assistant and is the largest EasyCrypt development to date.

We introduce Oblivious Key Management Systems (KMS) as a much more secure alternative to traditional wrapping-based KMS that form the backbone of key management in large-scale data storage deployments. The new system, that builds on Oblivious Pseudorandom Functions (OPRF), hides keys and object identifiers from the KMS, offers unconditional security for key transport, provides key verifiability, reduces storage, and more. Further, we show how to provide all these features in a distributed threshold implementation that enhances protection against server compromise. We extend this system with updatable encryption capability that supports key updates (known as key rotation) so that upon the periodic change of OPRF keys by the KMS server, a very efficient update procedure allows a client of the KMS service to non-interactively update all its encrypted data to be decryptable only by the new key. This enhances security with forward and post-compromise security, namely, security against future and past compromises, respectively, of the client's OPRF keys held by the KMS. Additionally, and in contrast to traditional KMS, our solution supports public key encryption and dispenses with any interaction with the KMS for data encryption (only decryption by the client requires such communication). Our solutions build on recent work on updatable encryption but with significant enhancements applicable to the remote KMS setting. In addition to the critical security improvements, our designs are highly efficient and ready for use in practice. We report on experimental implementation and performance.

Key management is critical for the successful operation of a cryptographic system in wireless networks. Systems based on asymmetric keys require a dedicated infrastructure for key management and authentication which may not be practical for ad-hoc Underwater Acoustic Networks (UANs). In symmetric-key systems, key distribution is not easy to handle when new nodes join the network. In addition, when a key is compromised all nodes that use the same key are not secure anymore. Hence, it is desirable to have a dynamic way to generate new keys without relying on past keys. Physical Layer Security (PLS) uses correlated channel measurements between two underwater nodes to generate a cryptographic key without exchanging the key itself. In this study, we set up a network of two legitimate nodes and one eavesdropper operating in a shallow area off the coast of Portugal. We propose novel features based on the Channel Impulse Response (CIR) of the established acoustic link that could be used as an initial seed for a crypto-key generation algorithm. Our results show that the two nodes can independently generate 306 quantization bits after exchanging 187 probe signals. Furthermore, the eavesdropper fails to generate the same bits from her/his data even if she/he performs exactly the same signal processing steps of the legitimate nodes.

Personal cryptographic keys are the foundation of many secure services, but storing these keys securely is a challenge, especially if they are used from multiple devices. Storing keys in a centralized location, like an Internet-accessible server, raises serious security concerns (e.g. server compromise). Hardware-based Trusted Execution Environments (TEEs) are a well-known solution for protecting sensitive data in untrusted environments, and are now becoming available on commodity server platforms. Although the idea of protecting keys using a server-side TEE is straight-forward, in this paper we validate this approach and show that it enables new desirable functionality. We describe the design, implementation, and evaluation of a TEE-based Cloud Key Store (CKS), an online service for securely generating, storing, and using personal cryptographic keys. Using remote attestation, users receive strong assurance about the behaviour of the CKS, and can authenticate themselves using passwords while avoiding typical risks of password-based authentication like password theft or phishing. In addition, this design allows users to i) define policy-based access controls for keys; ii) delegate keys to other CKS users for a specified time and/or a limited number of uses; and iii) audit all key usages via a secure audit log. We have implemented a proof of concept CKS using Intel SGX and integrated this into GnuPG on Linux and OpenKeychain on Android. Our CKS implementation performs approximately 6,000 signature operations per second on a single desktop PC. The latency is in the same order of magnitude as using locally-stored keys, and 20x faster than smart cards.

The Internet of Things (IoT) provides transparent and seamless incorporation of heterogeneous and different end systems. It has been widely used in many applications such as smart homes. However, people may resist the IOT as long as there is no public confidence that it will not cause any serious threats to their privacy. Effective secure key management for things authentication is the prerequisite of security operations. In this paper, we present an interactive key management protocol and a non-interactive key management protocol to minimize the communication cost of the things. The security analysis show that the proposed schemes are resilient to various types of attacks.

As 5G transitions from an industrial vision to a tangible, next-generation mobile technology, security remains key business driver. Heterogeneous environment, new networking paradigms and novel use cases makes 5G vulnerable to new security threats. This in turn necessitates a flexible and dependable security mechanism. End-to-End (E2E) data protection provides better security, avoids repeated security operations like encryption/decryption and provides differentiated security based on the services. E2E security deals with authentication, integrity, key management and confidentiality. The attack surface of a 5G system is larger as 5G aims for a heterogeneous networked society. Hence attack resistance needs to be a design consideration when defining new 5G protocols. This framework has been designed for accessing the manifold applications with high security and trust by offering E2E security for various services. The proposed framework is evaluated based on computation complexity, communication complexity, attack resistance rate and security defensive rate. The protocol is also evaluated for correctness, and resistance against passive, active and dictionary attacks using random oracle model and Automated Validation of Internet Security Protocols and Applications (AVISPA) tool.

When a large scale disaster strikes, it demands an efficient communication and coordination among first responders to save life and other community resources. Normally, the traditional communication infrastructures such as landline phone or cellular networks are damaged and dont provide adequate communication services to first responders for exchanging emergency related information. Wireless mesh networks is the promising alternatives in such type of situations. The security requirements for emergency response communications include privacy, data integrity, authentication, access control and availability. To build a secure communication system, usually the first attempt is to employ cryptographic keys. In critical-mission wireless mesh networks, a mesh router needs to maintain secure data communication with its neighboring mesh routers. The effective designs on fast pairwise key generation and rekeying for mesh routers are critical for emergency response and are essential to protect unicast traffic. In this paper, we present a security-enhanced session key generation and rekeying protocols EHPFS (enhanced 4-way handshake with PFS support). It eliminate the DoS attack problem of the 4-way handshake in 802.11s. EHPFS provides additional support for perfect forward secrecy (PFS). Even in case a Primary Master Key (PMK) is exposed, the session key PTK will not be compromised. The performance and security analysis show that EHPFS is efficient.

With the ever increasing DRAM capacity in commodity computers, applications tend to store large amount of data in main memory for fast access. Accordingly, efficient traversal of index structures to locate requested data becomes crucial to their performance. The index data structures grow so large that only a fraction of them can be cached in the CPU cache. The CPU cache can leverage access locality to keep the most frequently used part of an index in it for fast access. However, the traversal on the index to a target data during a search for a data item can result in significant false temporal and spatial localities, which make CPU cache space substantially underutilized. In this paper we show that even for highly skewed accesses the index traversal incurs excessive cache misses leading to suboptimal data access performance. To address the issue, we introduce Search Lookaside Buffer (SLB) to selectively cache only the search results, instead of the index itself. SLB can be easily integrated with any index data structure to increase utilization of the limited CPU cache resource and improve throughput of search requests on a large data set. We integrate SLB with various index data structures and applications. Experiments show that SLB can improve throughput of the index data structures by up to an order of magnitude. Experiments with real-world key-value traces also show up to 73% throughput improvement on a hash table.

Wireless communications in Cyber-Physical Systems (CPS) are vulnerable to many adversarial attacks such as eavesdropping. To secure the communications, secret session keys need to be established between wireless devices. In existing symmetric key establishment protocols, it is assumed that devices are pre-loaded with secrets. In the CPS, however, wireless devices are produced by different companies. It is not practical to assume that the devices are pre-loaded with certain secrets when they leave companies. As a consequence, existing symmetric key establishment protocols cannot be directly implemented in the CPS. Motivated by these observations, this paper presents a cross-layer key establishment model for heterogeneous wireless devices in the CPS. Specifically, by implementing our model, wireless devices extract master keys (shared with the system authority) at the physical layer using ambient wireless signals. Then, the system authority distributes secrets for devices (according to an existing symmetric key establishment protocol) by making use of the extracted master keys. Completing these operations, wireless devices can establish secret session keys at higher layers by calling the employed key establishment protocol. Additionally, we prove the security of the proposed model. We analyse the performance of the new model by implementing it and converting existing symmetric key establishment protocols into cross-layer key establishment protocols.