Biblio

The damage caused by counterfeits of semiconductors has become a serious problem. Recently, a physical unclonable function (PUF) has attracted attention as a technique to prevent counterfeiting. The present study investigates an arbiter PUF, which is a typical PUF. The vulnerability of a PUF against machine-learning attacks has been revealed. It has also been indicated that the output of a PUF is inverted from its normal output owing to the difference in environmental variations, such as the changes in power supply voltage and temperature. The resistance of a PUF against machine-learning attacks due to the difference in environmental variation has seldom been evaluated. The present study evaluated the resistance of an arbiter PUF against machine-learning attacks due to the difference in environmental variation. By performing an evaluation experiment using a simulation, the present study revealed that the resistance of an arbiter PUF against machine-learning attacks due to environmental variation was slightly improved. However, the present study also successfully predicted more than 95% of the outputs by increasing the number of learning cycles. Therefore, an arbiter PUF was revealed to be vulnerable to machine-learning attacks even after environmental variation.

This paper develops a new lightweight secure sensing technique using hardware isolation. We focus on protecting the sensor from unauthorized accesses, which can be issued by attackers attempting to compromise the security and privacy of the sensed data. We satisfy the security requirements by employing the hardware isolation feature provided by the secure processor of the target sensor system. In particular, we deploy the sensor in a hardware isolated secure environment, which eliminates the potential vulnerability exposed to unauthorized attackers. We implement the hardware isolation-based secure sensing approach on an Xilinx Zynq-7000 SoC leveraging ARM TrustZone. Our experiments and security analysis on the real hardware prove the effectiveness and low overhead of the proposed approach.

The threats of reverse-engineering, IP piracy, and hardware Trojan insertion in the semiconductor supply chain are greater today than ever before. Split manufacturing has emerged as a viable approach to protect integrated circuits (ICs) fabricated in untrusted foundries, but has high cost and/or high performance overhead. Furthermore, split manufacturing cannot fully prevent untargeted hardware Trojan insertions. In this paper, we propose to insert additional functional circuitry called obfuscated built-in self-authentication (OBISA) in the chip layout with split manufacturing process, in order to prevent reverse-engineering and further prevent hardware Trojan insertion. Self-tests are performed to authenticate the trustworthiness of the OBISA circuitry. The OBISA circuit is connected to original design in order to increase the strength of obfuscation, thereby allowing a higher layer split and lower overall cost. Additional fan-outs are created in OBISA circuitry to improve obfuscation without losing testability. Our proposed gating mechanism and net selection method can ensure negligible overhead in terms of area, timing, and dynamic power. Experimental results demonstrate the effectiveness of the proposed technique in several benchmark circuits.

In this paper, we study the security and system congestion in a risk-based checkpoint screening system with two kinds of inspection queues, named as Selectee Lanes and Normal Lanes. Based on the assessed threat value, the arrival crossing the security checkpoints is classified as either a selectee or a non-selectee. The Selectee Lanes with enhanced scrutiny are used to check selectees, while Normal Lanes are used to check non-selectees. The goal of the proposed modelling framework is to minimize the system congestion under the constraints of total security and limited budget. The system congestion of the checkpoint screening system is determined through a steady-state analysis of multi-server queueing models. By solving an optimization model, we can determine the optimal threshold for differentiating the arrivals, and determine the optimal number of security devices for each type of inspection queues. The analysis conducted in this study contributes managerial insights for understanding the operation and system performance of such risk-based checkpoint screening systems.

This paper presents an efficiency and adaptive cryptographic protocol to ensure users' privacy and data integrity in RFID system. Radio Frequency Identification technology offers more intelligent systems and applications, but privacy and security issues have to be addressed before and after its adoption. The design of the proposed model is based on clustering configuration of the involved tags where they interchange the data with the reader whenever it sends a request. This scheme provides a strong mutual authentication framework that suits for real heterogeneous RFID applications such as in supply-chain management systems, healthcare monitoring and industrial environment. In addition, we contribute with a mathematical analysis to the delay analysis and optimization in a clustering topology tag-based. Finally, a formal security and proof analysis is demonstrated to prove the effectiveness of the proposed protocol and that achieves security and privacy.

There are relatively fewer studies on the security-check waiting lines for screening cargo containers using queueing models. In this paper, we address two important measures at a security-check system, which are concerning the security screening effectiveness and the efficiency. The goal of this paper is to provide a modelling framework to understand the economic trade-offs embedded in container-inspection decisions. In order to analyze the policy initiatives, we develop a stylized queueing model with the novel features pertaining to the security checkpoints.

The main challenge of ultra-reliable machine-to-machine (M2M) control applications is to meet the stringent timing and reliability requirements of control systems, despite the adverse properties of wireless communication for delay and packet errors, and limited battery resources of the sensor nodes. Since the transmission delay and energy consumption of a sensor node are determined by the transmission power and rate of that sensor node and the concurrently transmitting nodes, the transmission schedule should be optimized jointly with the transmission power and rate of the sensor nodes. Previously, it has been shown that the optimization of power control and rate adaptation for each node subset can be separately formulated, solved and then used in the scheduling algorithm in the optimal solution of the joint optimization of power control, rate adaptation and scheduling problem. However, the power control and rate adaptation problem has been only formulated and solved for continuous rate transmission model, in which Shannon's capacity formulation for an Additive White Gaussian Noise (AWGN) wireless channel is used in the calculation of the maximum achievable rate as a function of Signal-to-Interference-plus-Noise Ratio (SINR). In this paper, we formulate the power control and rate adaptation problem with the objective of minimizing the time required for the concurrent transmission of a set of sensor nodes while satisfying their transmission delay, reliability and energy consumption requirements based on the more realistic discrete rate transmission model, in which only a finite set of transmit rates are supported. We propose a polynomial time algorithm to solve this problem and prove the optimality of the proposed algorithm. We then combine it with the previously proposed scheduling algorithms and demonstrate its close to optimal performance via extensive simulations.

The passive radar also known as Green Radar exploits the available commercial communication signals and is useful for target tracking and detection in general. Recent communications standards frequently employ Orthogonal Frequency Division Multiplexing (OFDM) waveforms and wideband for broadcasting. This paper focuses on the recent developments of the target detection algorithms in the OFDM passive radar framework where its channel estimates have been derived using the matched filter concept using the knowledge of the transmitted signals. The MUSIC algorithm, which has been modified to solve this two dimensional delay-Doppler detection problem, is first reviewed. As the target detection problem can be represented as sparse signals, this paper employs compressive sensing to compare with the detection capability of the 2-D MUSIC algorithm. It is found that the previously proposed single time sample compressive sensing cannot significantly reduce the leakage from the direct signal component. Furthermore, this paper proposes the compressive sensing method utilizing multiple time samples, namely l1-SVD, for the detection of multiple targets. In comparison between the MUSIC and compressive sensing, the results show that l1-SVD can decrease the direct signal leakage but its prerequisite of computational resources remains a major issue. This paper also presents the detection performance of these two algorithms for closely spaced targets.

Design-time analysis and verification of distributed real-time embedded systems necessitates the modeling of the time-varying performance of the network and comparing that to application requirements. Earlier work has shown how to build a system network model that abstracted away the network's physical medium and protocols which govern its access and multiplexing. In this work we show how to apply a network medium channel access protocol, such as Time-Division Multiple Access (TDMA), to our network analysis methods and use the results to show that the abstracted model without the explicit model of the protocol is valid.

In this paper, we propose an accumulated loss recovery algorithm on overlay multicast system using Fountain codes. Fountain code successfully decodes the packet loss, but it is weak in accumulated losses on multicast tree. The proposed algorithm overcomes an accumulated loss and significantly reduces delay on overlay multicast tree.
 

We propose Authentication and Key Agreement (AKA) for Machine Type Communications (MTC) in LTE-Advanced. This protocol is based on an idea of grouping devices so that it would reduce signaling congestion in the access network and overload on the single authentication server. We verified that this protocol is designed to be secure against many attacks by using a software verification tool. Furthermore, performance evaluation suggests that this protocol is efficient with respect to authentication overhead and handover delay.
 

With the rapid development of Wireless Sensor Networks (WSNs), besides the energy efficient, Quality of Service (QoS) supported and the validity of packet transmission should be considered under some circumstances. In this paper, according to summing up LEACH protocol's advantages and defects, combining with trust evaluation mechanism, energy and QoS control, a trust-based QoS routing algorithm is put forward. Firstly, energy control and coverage scale are adopted to keep load balance in the phase of cluster head selection. Secondly, trust evaluation mechanism is designed to increase the credibility of the network in the stage of node clusting. Finally, in the period of information transmission, verification and ACK mechanism also put to guarantee validity of data transmission. In this paper, it proposes the improved protocol. The improved protocol can not only prolong nodes' life expectancy, but also increase the credibility of information transmission and reduce the packet loss. Compared to typical routing algorithms in sensor networks, this new algorithm has better performance.

In this paper, we consider the impact of a weaker model of eventual consistency on distributed multi-player games. This model is suitable for networks in which hosts can leave and join at anytime, e.g., in an intermittently connected environment. Such a consistency model is provided by the Secure Infrastructure for Networked Systems (SINS) [24], a reliable middleware framework. SINS allows agents to communicate asynchronously through a distributed transactional key-value store using anonymous publish-subscribe. It uses Lamport's Paxos protocol [17] to replicate state. We consider a multi-player maze game as example to illustrate our consistency model and the impact of network losses/delays therein. The framework based on SINS presented herein provides a vehicle for studying the effect of human elements participating in collaborative simulation of a physical world as in war games.

Mobile Ad-hoc Network is highly susceptible towards the security attacks due to its dynamic topology, resource constraint, energy constraint operations, limited physical security and lack of infrastructure. Misleading routing attack (MIRA) in MANET intend to delay packet to its fullest in order to generate time outs at the source as packets will not reach in time. Its main objective is to generate delay and increase network overhead. It is a variation to the sinkhole attack. In this paper, we have proposed a detection scheme to detect the malicious nodes at route discovery as well as at packet transmissions. The simulation results of MIRA attack indicate that though delay is increased by 91.30% but throughput is not affected which indicates that misleading routing attack is difficult to detect. The proposed detection scheme when applied to misleading routing attack suggests a significant decrease in delay.

Timing slacks possibly lead to reliability issues and/or security vulnerabilities, as they may hide small delay defects and malicious circuitries injected during fabrication, namely, hardware Trojans. While possibly harmless immediately after production, small delay defects may trigger reliability problems as the part is being used in field, presenting a significant threat for mission-critical applications. Hardware Trojans remain dormant while the part is tested and validated, but then get activated to launch an attack when the chip is deployed in security-critical applications. In this paper, we take a deeper look into these problems and their underlying reasons, and propose a design technique to maximize the detection of small delay defects as well as the hardware Trojans. The proposed technique eliminates all slacks by judiciously inserting delay units in a small set of locations in the circuit, thereby rendering a simple set of transition fault patterns quite effective in catching parts with small delay defects or Trojans. Experimental results also justify the efficacy of the proposed technique in improving the quality of test while retaining the pattern count and care bit density intact.
 

This paper discusses the detection of hardware Trojans (HTs) by their breaking of symmetries within integrated circuits (ICs), as measured by path delays. Typically, path delay or side channel methods rely on comparisons to a golden, or trusted, sample. However, golden standards are affected by inter-and intra-die variations which limit the confidence in such comparisons. Symmetry is a way to detect modifications to an IC with increased confidence by confirming subcircuit consistencies within as it was originally designed. The difference in delays from a given path to a set of symmetric paths will be the same unless an inserted HT breaks symmetry. Symmetry can naturally exist in ICs or be artificially added. We describe methods to find and measure path delays against symmetric paths, as well as the advantages and disadvantages of this method. We discuss results of examples from benchmark circuits demonstrating the detection of hardware Trojans.
 

Detecting hardware Trojan is a difficult task in general. The context is that of a fabless design house that sells IP blocks as GDSII hard macros, and wants to check that final products have not been infected by Trojan during the foundry stage. In this paper we analyzed hardware Trojan horses insertion and detection in Scalable Encryption Algorithm (SEA) crypto. We inserted Trojan at different levels in the ASIC design flow of SEA crypto and most importantly we focused on Gate level and layout level Trojan insertions. We choose path delays in order to detect Trojan at both levels in design phase. Because the path delays detection technique is cost effective and efficient method to detect Trojan. The comparison of path delays makes small Trojan circuits significant from a delay point of view. We used typical, fast and slow 90nm libraries in order to estimate the efficiency of path delay technique in different operating conditions. The experiment's results show that the detection rate on payload Trojan is 100%.
 

Malicious hardware is a realistic threat. It can be possible to insert the malicious functionality on a device as deep as in the hardware design flow, long before manufacturing the silicon product. Towards developing a hardware Trojan horse detection methodology, we analyze capabilities and limitations of existing techniques, framing a testing strategy for uncovering efficiently hardware Trojan horses in mass-produced integrated circuits.
 

Voting among replicated data collection devices is a means to achieve dependable data delivery to the end-user in a hostile environment. Failures may occur during the data collection process: such as data corruptions by malicious devices and security/bandwidth attacks on data paths. For a voting system, how often a correct data is delivered to the user in a timely manner and with low overhead depicts the QoS. Prior works have focused on algorithm correctness issues and performance engineering of the voting protocol mechanisms. In this paper, we study the methods for autonomic management of device replication in the voting system to deal with situations where the available network bandwidth fluctuates, the fault parameters change unpredictably, and the devices have battery energy constraints. We treat the voting system as a `black-box' with programmable I/O behaviors. A management module exercises a macroscopic control of the voting box with situational inputs: such as application priorities, network resources, battery energy, and external threat levels.
 

This article is a summary description of the Cognitive Packet Network (CPN) which is an example both of a completely software defined network (SDN) and of a self-aware computer network (SAN) which has been completely implemented and used in numerous experiments. CPN is able to observe its own internal performance as well as the interfaces of the external systems that it interacts with, in order to modify its behaviour so as to adaptively achieve objectives, such as discovering services for its users, improving their Quality of Service (QoS), reduce its own energy consumption, compensate for components which fail or malfunction, detect and react to intrusions, and defend itself against attacks.
 

The time delay of echo generated by the moving target simulator based on digital delay technique is discrete. So there are range and phase errors between the simulated target and real target, and the simulated target will move discontinuously due to the discrete time delay. In order to solve this problem and generate a continuously moving target, this paper uses signal processing technique to adjust the range and phase errors between the two targets. By adjusting the range gate, the time delay error is reduced to be smaller than sampling interval. According to the relationship between range and phase, the left error within one range bin can be removed equivalently by phase compensation. The simulation results show that by adjusting the range gate, the time delay errors are greatly reduced, and the left errors can be removed by phase compensation. In other words, a real continuously moving target is generated and the problem is solved.
 

Since the massive deployment of Cyber-Physical Systems (CPSs) calls for long-range and reliable communication services with manageable cost, it has been believed to be an inevitable trend to relay a significant portion of CPS traffic through existing networking infrastructures such as the Internet. Adversaries who have access to networking infrastructures can therefore eavesdrop network traffic and then perform traffic analysis attacks in order to identify CPS sessions and subsequently launch various attacks. As we can hardly prevent all adversaries from accessing network infrastructures, thwarting traffic analysis attacks becomes indispensable. Traffic morphing serves as an effective means towards this direction. In this paper, a novel traffic morphing algorithm, CPSMorph, is proposed to protect CPS sessions. CPSMorph maintains a number of network sessions whose distributions of inter-packet delays are statistically indistinguishable from those of typical network sessions. A CPS message will be sent through one of these sessions with assured satisfaction of its time constraint. CPSMorph strives to minimize the overhead by dynamically adjusting the morphing process. It is characterized by low complexity as well as high adaptivity to changing dynamics of CPS sessions. Experimental results have shown that CPSMorph can effectively performing traffic morphing for real-time CPS messages with moderate overhead.
 

In this paper, we propose techniques for combating source selective jamming attacks in tactical cognitive MANETs. Secure, reliable and seamless communications are important for facilitating tactical operations. Selective jamming attacks pose a serious security threat to the operations of wireless tactical MANETs since selective strategies possess the potential to completely isolate a portion of the network from other nodes without giving a clear indication of a problem. Our proposed mitigation techniques use the concept of address manipulation, which differ from other techniques presented in open literature since our techniques employ de-central architecture rather than a centralized framework and our proposed techniques do not require any extra overhead. Experimental results show that the proposed techniques enable communications in the presence of source selective jamming attacks. When the presence of a source selective jammer blocks transmissions completely, implementing a proposed flipped address mechanism increases the expected number of required transmission attempts only by one in such scenario. The probability that our second approach, random address assignment, fails to solve the correct source MAC address can be as small as 10-7 when using accurate parameter selection.

Software-Defined Networking (SDN) allows network capabilities and services to be managed through a central control point. Moving Target Defense (MTD) on the other hand, introduces a constantly adapting environment in order to delay or prevent attacks on a system. MTD is a use case where SDN can be leveraged in order to provide attack surface obfuscation. In this paper, we investigate how SDN can be used in some network-based MTD techniques. We first describe the advantages and disadvantages of these techniques, the potential countermeasures attackers could take to circumvent them, and the overhead of implementing MTD using SDN. Subsequently, we study the performance of the SDN-based MTD methods using Cisco's One Platform Kit and we show that they significantly increase the attacker's overheads.

This paper proposes a new cross-layer based packet scheduling scheme for multimedia traffic in satellite Long Term Evolution (LTE) network which adopts MIMO technology. The Satellite LTE air interface will provide global coverage and hence complement its terrestrial counterpart in the provision of mobile services (especially multimedia services) to users across the globe. A dynamic packet scheduling scheme is very important towards actualizing an effective utilization of the limited available resources in satellite LTE networks without compromise to the Quality of Service (QoS) demands of multimedia traffic. Hence, the need for an effective packet scheduling algorithm cannot be overemphasized. The aim of this paper is to propose a new scheduling algorithm tagged Cross-layer Based Queue-Aware (CBQA) Scheduler that will provide a good trade-off among QoS, fairness and throughput. The newly proposed scheduler is compared to existing ones through simulations and various performance indices have been used. A land mobile dual-polarized GEO satellite system has been considered for this work.