Biblio

The Named Data Network (NDN) is a promising network paradigm for content distribution based on caching. However, it may put consumer privacy at risk, as the adversary may identify the content, the name and the signature (namely a certificate) through side-channel timing responses from the cache of the routers. The adversary may identify the content name and the consumer node by distinguishing between cached and un- cached contents. In order to mitigate the timing attack, effective countermeasure methods have been proposed by other authors, such as random caching, random freshness, and probabilistic caching. In this work, we have implemented a timing attack scenario to evaluate the efficiency of these countermeasures and to demonstrate how the adversary can be detected. For this goal, a brute force timing attack scenario based on a real topology was developed, which is the first brute force attack model applied in NDN. Results show that the adversary nodes can be effectively distinguished from other legitimate consumers during the attack period. It is also proposed a multi-level mechanism to detect an adversary node. Through this approach, the content distribution performance can be mitigated against the attack.

Delivery service via ridesharing is a promising service to share travel costs and improve vehicle occupancy. Existing ridesharing systems require participating vehicles to periodically report individual private information (e.g., identity and location) to a central controller, which is a potential central point of failure, resulting in possible data leakage or tampering in case of controller break down or under attack. In this paper, we propose a Blockchain secured ridesharing delivery system, where the immutability and distributed architecture of the Blockchain can effectively prevent data tampering. However, such tamper-resistance property comes at the cost of a long confirmation delay caused by the consensus process. A Hash-oriented Practical Byzantine Fault Tolerance (PBFT) based consensus algorithm is proposed to improve the Blockchain efficiency and reduce the transaction confirmation delay from 10 minutes to 15 seconds. The Hash-oriented PBFT effectively avoids the double-spending attack and Sybil attack. Security analysis and simulation results demonstrate that the proposed Blockchain secured ridesharing delivery system offers strong security guarantees and satisfies the quality of delivery service in terms of confirmation delay and transaction throughput.

Hardware Trojan threats caused by malicious designers and untrusted manufacturers have become one of serious issues in modern VLSI systems. In this paper, we show some experimental results to insert hardware Trojans into asynchronous circuits. As a result, the overhead of hardware Trojan insertion in asynchronous circuits may be small for malicious designers who have enough knowledge about the asynchronous circuits. In addition, we also show several Trojan detection methods using deep learning schemes which have been proposed to detect synchronous hardware Trojan in the netlist level. We apply them to asynchronous hardware Trojan circuits and show their results. They have a great potential to detect a hardware Trojan in asynchronous circuits.

With the rapid increase in the use of mobile devices in people's daily lives, mobile data traffic is exploding in recent years. In the edge computing environment where edge servers are deployed around mobile users, caching popular data on edge servers can ensure mobile users' fast access to those data and reduce the data traffic between mobile users and the centralized cloud. Existing studies consider the data cache problem with a focus on the reduction of network delay and the improvement of mobile devices' energy efficiency. In this paper, we attack the data caching problem in the edge computing environment from the service providers' perspective, who would like to maximize their venues of caching their data. This problem is complicated because data caching produces benefits at a cost and there usually is a trade-off in-between. In this paper, we formulate the data caching problem as an integer programming problem, and maximizes the revenue of the service provider while satisfying a constraint for data access latency. Extensive experiments are conducted on a real-world dataset that contains the locations of edge servers and mobile users, and the results reveal that our approach significantly outperform the baseline approaches.

Caching methods are developed since 50 years for paging in CPU and database systems, and since 25 years for web caching as main application areas among others. Pages of unique size are usual in CPU caches, whereas web caches are storing data chunks of different size in a widely varying range. We study the impact of different object sizes on the performance and the overhead of web caching. This entails different caching goals, starting from the byte and object hit ratio to a generalized value hit ratio for optimized costs and benefits of caching regarding traffic engineering (TE), reduced delays and other QoS measures. The selection of the cache contents turns out to be crucial for the web cache efficiency with awareness of the size and other properties in a score for each object. We introduce a new class of rank exchange caching methods and show how their performance compares to other strategies with extensions needed to include the size and scores for QoS and TE caching goals. Finally, we derive bounds on the object, byte and value hit ratio for the independent request model (IRM) based on optimum knapsack solutions of the cache content.

As Web traffics is increasing on the Internet, caching solutions for Web systems are becoming more important since they can greatly expand system scalability. An important part of a caching solution is cache replacement policy, which is responsible for selecting victim items that should be removed in order to make space for new objects. Typical replacement policies used in practice only take advantage of temporal reference locality by removing the least recently/frequently requested items from the cache. Although those policies work well in memory or filesystem cache, they are inefficient for Web systems since they do not exploit semantic relationship between Web items. This paper presents a semantic-aware caching policy that can be used in Web systems to enhance scalability. The proposed caching mechanism defines semantic distance from a web page to a set of pivot pages and use the semantic distances as a metric for choosing victims. Also, it use a function-based metric that combines access frequency and cache item size for tie-breaking. Our simulations show that out enhancements outperform traditional methods in terms of hit rate, which can be useful for websites with many small and similar-in-size web objects.

Atomic multicast is a communication primitive that delivers messages to multiple groups of processes according to some total order, with each group receiving the projection of the total order onto messages addressed to it. To be scalable, atomic multicast needs to be genuine, meaning that only the destination processes of a message should participate in ordering it. In this paper we propose a novel genuine atomic multicast protocol that in the absence of failures takes as low as 3 message delays to deliver a message when no other messages are multicast concurrently to its destination groups, and 5 message delays in the presence of concurrency. This improves the latencies of both the fault-tolerant version of classical Skeen's multicast protocol (6 or 12 message delays, depending on concurrency) and its recent improvement by Coelho et al. (4 or 8 message delays). To achieve such low latencies, we depart from the typical way of guaranteeing fault-tolerance by replicating each group with Paxos. Instead, we weave Paxos and Skeen's protocol together into a single coherent protocol, exploiting opportunities for white-box optimisations. We experimentally demonstrate that the superior theoretical characteristics of our protocol are reflected in practical performance pay-offs.

Scalability is an important design factor for evaluating the performance of routing protocols as the network size or traffic load increases. One of the most appropriate design methods is to use geographic routing approach to ensure scalability. This paper describes a scalability study comparing Secure Region Based Geographic Routing (SRBGR) and Dynamic Window Secure Implicit Geographic Forwarding (DWSIGF) protocols in various network density scenarios based on an end-to-end delay performance metric. The simulation studies were conducted in MATLAB 2106b where the network densities were varied according to the network topology size with increasing traffic rates. The results showed that DWSIGF has a lower end-to-end delay as compared to SRBGR for both sparse (15.4%) and high density (63.3%) network scenarios.Despite SRBGR having good security features, there is a need to improve the performance of its end-to-end delay to fulfil the application requirements.

Routing protocols in wireless sensor network are vulnerable to various malicious security attacks that can degrade network performance and lifetime. This becomes more important in cluster routing protocols that is composed of multiple node and cluster head, such as low energy adaptive clustering hierarchy (LEACH) protocol. Namely, if an attack succeeds in failing the cluster head, then the entire set of nodes fail. Therefore, it is necessary to develop robust recovery schemes to overcome security attacks and recover packets at short times. Hence this paper proposes a detection and recovery scheme for selective forwarding attacks in wireless sensor networks using LEACH protocol. The proposed solution features near-instantaneous recovery times, without the requirement for feedback or retransmissions once an attack occurs.

The new generation ship integrated power system (IPS) realizes high level informatization for various physical equipments, and gradually develops to a cyber-physical system (CPS). The future trend is collecting ship big data to achieve data-driven intelligence for IPS. However, traditional relational data management framework becomes inefficient to handle the real-time data processing in ship integrated power cyber-physics system. In order to process the large-scale real-time data that collected from numerous sensors by field bus of IPS devices within acceptable latency, especially for handling the semi-structured and non-structured data. This paper proposes a novel key-value data model based real-time data management framework, which enables batch processing and distributed deployment to acquire time-efficiency as well as system scalable. We implement a real-time data management prototype system based on an open source in-memory key-value store. Finally, the evaluation results from the prototype verify the advantages of novel framework compared with traditional solution.

Named Data Networking (NDN) is a promising candidate for future internet architecture. It is one of the implementations of the Information-Centric Networking (ICN) architectures where the focus is on the data rather than the owner of the data. While the data security is assured by definition, these networks are susceptible of various Denial of Service (DoS) attacks, mainly Interest Flooding Attacks (IFA). IFAs overwhelm an NDN router with a huge amount of interests (Data requests). Various solutions have been proposed in the literature to mitigate IFAs; however; these solutions do not make a difference between intentional and unintentional misbehavior due to the network congestion. In this paper, we propose a novel congestion-aware IFA detection and mitigation solution. We performed extensive simulations and the results clearly depict the efficiency of our proposal in detecting truly occurring IFA attacks.

A key challenge of the embedded era is to ensure trust in reuse of intellectual properties (IPs), which facilitates reduction of design cost and meeting of stringent marketing deadlines. Determining source of the IPs or their authenticity is a key metric to facilitate safe reuse of IPs. Though physical unclonable functions solves this problem for application specific integrated circuit (ASIC) IPs, authentication strategies for reconfigurable IPs (RIPs) or IPs of reconfigurable hardware platforms like field programmable gate arrays (FPGAs) are still in their infancy. Existing authentication techniques for RIPs that relies on verification of proof of authentication (PoA) mark embedded in the RIP by the RIP producers, leak useful clues about the PoA mark. This results in replication and implantation of the PoA mark in fake RIPs. This not only causes loss to authorized second hand RIP users, but also poses risk to the reputation of the RIP producers. We propose a zero knowledge authentication strategy for safe reusing of RIPs. The PoA of an RIP producer is kept secret and verification is carried out based on traversal times from the initial point to several intermediate points of the embedded PoA when the RIPs configure an FPGA. Such delays are user specific and cannot be replicated as these depend on intrinsic properties of the base semiconductor material of the FPGA, which is unique and never same as that of another FPGA. Experimental results validate our proposed mechanism. High strength even for low overhead ISCAS benchmarks, considered as PoA for experimentation depict the prospects of our proposed methodology.

Fog computing extends cloud computing technology to the edge of the infrastructure to support dynamic computation for IoT applications. Reduced latency and location awareness in objects' data access is attained by displacing workloads from the central cloud to edge devices. Doing so, it reduces raw data transfers from target objects to the central cloud, thus overcoming communication bottlenecks. This is a key step towards the pervasive uptake of next generation IoT-based services. In this work we study efficient orchestration of applications in fog computing, where a fog application is the cascade of a cloud module and a fog module. The problem results into a mixed integer non linear optimisation. It involves multiple constraints due to computation and communication demands of fog applications, available infrastructure resources and it accounts also the location of target IoT objects. We show that it is possible to reduce the complexity of the original problem with a related placement formulation, which is further solved using a greedy algorithm. This algorithm is the core placement logic of FogAtlas, a fog computing platform based on existing virtualization technologies. Extensive numerical results validate the model and the scalability of the proposed algorithm, showing performance close to the optimal solution with respect to the number of served applications.

Series-connected IGBTs, when properly controlled, operate similarly to a single device with a much higher voltage capacity. Integrating series IGBTs into a Modular Multilevel Converter (MMC) can reduce its complexity without compromising the voltage capacity. This paper presents the circuit design on the sub-modular level of a MMC in which all the switching devices are series-connected IGBTs. The voltage sharing among the series IGBTs are regulated in a self-balancing manner. Therefore, no central series IGBT controller is needed, which greatly reduces the sensing and communication complexities, increasing the flexibility and expandability. Hardware experiment results demonstrate that the series IGBTs are able to self-regulate the voltage sharing in a fast and accurate manner and the system can operate similarly to a sub-module in a MMC.

Due to its costly and time-consuming nature and a wide range of passive barrier elements and tools for their breaching, testing the delay time of passive barriers is only possible as an experimental tool to verify expert judgements of said delay times. The article focuses on the possibility of creating and utilizing a new method of acquiring values of delay time for various passive barrier elements using expert judgements which could add to the creation of charts where interactions between the used elements of mechanical barriers and the potential tools for their bypassing would be assigned a temporal value. The article consists of basic description of methods of expert judgements previously applied for making prognoses of socio-economic development and in other societal areas, which are called soft system. In terms of the problem of delay time, this method needed to be modified in such a way that the prospective output would be expressible by a specific quantitative value. To achieve this goal, each stage of the expert judgements was adjusted to the use of suitable scientific methods to select appropriate experts and then to achieve and process the expert data. High emphasis was placed on evaluation of quality and reliability of the expert judgements, which takes into account the specifics of expert selection such as their low numbers, specialization and practical experience.

Cybersecurity in control systems has been actively discussed in recent years. In particular, networked control systems (NCSs) over the Internet are exposed to various types of cyberattacks such as false data injection attacks. This paper proposes a detection and mitigation method of the false data injection attacks in interactive NCSs, i.e., bilateral teleoperation systems. A bilateral teleoperation system exchanges position and force information through the Internet between the master and slave robots. The proposed method utilizes two redundant communication channels for both the master-to-slave and slave-to-master paths. The attacks are detected by a tamper detection observer (TDO) on each of the master and slave sides. The TDO compares the position responses of actual robots and robot models. A path selector on each side chooses the appropriate position and force responses from the responses received through the two communication channels, based on the outputs of the TDO. The proposed method is validated by simulations with attack models.

Fog-Cloud framework is being regarded as a more promising technology to provide performance guarantee for IoT applications, which not only have higher requirements on computation resources, but also are delay and/or security sensitive. In this framework, a delay and security-sensitive computation task is usually divided into several sub-tasks, which could be offloaded to either fog or cloud computing servers, referred to as offloading destinations. Sub-tasks may exchange information during their processing and then have requirement on transmission bandwidth. Different destinations produce different completion delays of a sub-task, affecting the corresponding task delay. The existing offloading approaches either considered only a single type of offloading destinations or ignored delay and/or security constraint. This paper studies a computation offloading problem in the fog-cloud scenario where not only computation and security capabilities of offloading destinations may be different, but also bandwidth and delay of links may be different. We first propose a joint offloading approach by formulating the problem as a form of Mixed Integer Programming Multi-Commodity Flow to maximize the fog-cloud provider's revenue without sacrificing performance and security requirements of users. We also propose a greedy algorithm for the problem. Extensive simulation results under various network scales show that the proposed computation offloading mechanism achieves higher revenue than the conventional single-type computation offloading under delay and security constraints.

Reliability of electronic devices in sub-nanometer technology scale has become a major concern. However, demand for battery operated low power, high performance devices necessitates technology scaling. To meet these contradictory design goals optimization and reliability must be performed simultaneously. This paper proposes by integrating compiler driven transformation and simulated annealing based optimization process for generating optimized low cost transient fault tolerant DSP core. The case study on FIR filter shows improved performance (in terms of reduced area and delay) of proposed approach in comparison to state-of-art transient fault tolerant approach.

Conventional SDN-based MTD techniques have been mainly developed with a single SDN controller which exposes a single point of failure as well as raises a scalability issue for large-scale networks in achieving both security and performance. The use of multiple SDN controllers has been proposed to ensure both performance and security of SDN-based MTD systems for large-scale networks; however, the effect of using multiple SDN controllers has not been investigated in the state-of-the-art research. In this paper, we propose the SDN based MTD architecture using multiple SDN controllers and validate their security effect (i.e., attack success probability) by implementing an IP shuffling MTD in a testbed using ONOS SDN controllers.

Todays analyzing web weaknesses and vulnerabilities in order to find security attacks has become more urgent. In case there is a communication contrary to the system security policies, a covert channel has been created. The attacker can easily disclosure information from the victim's system with just one public access permission. Covert timing channels, unlike covert storage channels, do not have memory storage and they draw less attention. Different methods have been proposed for their identification, which generally benefit from the shape of traffic and the channel's regularity. In this article, an entropy-based detection method is designed and implemented. The attacker can adjust the amount of channel entropy by controlling measures such as changing the channel's level or creating noise on the channel to protect from the analyst's detection. As a result, the entropy threshold is not always constant for detection. By comparing the entropy from different levels of the channel and the analyst, we conclude that the analyst must investigate traffic at all possible levels.

Cross layer based approaches are increasingly becoming popular in Manet (Mobile Adhoc Network). As Manet are constrained with issues as low battery, limited bandwidth, link breakage and dynamic topology, cross layer based designs are trying to remove such barriers and trying to make Manet more scalable. Cross layer designs are also facing attacking problem and ensuring the security of network to defend the attack is must. In this paper we discuss about technique to optimize the performance by minimizing delay and overhead of secure cross layer routing protocol. We have designed SCLPC (Secure cross layer based Power control) protocol. But when security is imposed using AASR (Authenticated and anonymous secure routing), the network metrics as end to end delay and control overhead is disturbed. To optimize the network performance here we proposed OSCLPC (Optimized secure cross layer based power control protocol). The proposed OSCLPC has been evaluated using SHORT (Self healing and optimizing route technique). The OSCLPC is simulated in ns2 and it is giving the better performance compared with SCLPC.

Mobile ad hoc networks (MANETs) are a set of mobile wireless nodes that can communicate without the need for an infrastructure. Features of MANETs have made them vulnerable to many security attacks including wormhole attack. In the past few years, different methods have been introduced for detecting, mitigating, and preventing wormhole attacks in MANETs. In this paper, we introduce a new decentralized scheme based on statistical metrics for detecting wormholes that employs “number of new neighbors” along with “number of neighbors” for each node as its parameters. The proposed scheme has considerably low detection delay and does not create any traffic overhead for routing protocols which include neighbor discovery mechanism. Also, it possesses reasonable processing power and memory usage. Our simulation results using NS3 simulator show that the proposed scheme performs well in terms of detection accuracy, false positive rate and mean detection delay.

A “Completely Automated Public Turing Test to Tell Computers and Humans Apart” (CAPTCHA) widely used online services so that prevents bots from automatic getting a large of accounts. Interactive video type CAPTCHAs that attempt to detect this attack by using delay time due to communication relays have been proposed. However, these approaches remain insufficiently resistant to bots. We propose a CAPTCHA that combines resistant to automated and relay attacks. In our CAPTCHA, the users recognize a moving object (target object) from among a number of randomly appearing decoy objects and tracks the target with mouse cursor. The users pass the test when they were able to track the target for a certain time. Since the target object moves quickly, the delay makes it difficult for a remote solver to break the CAPTCHA during a relay attack. It is also difficult for a bot to track the target using image processing because it has same looks of the decoys. We evaluated our CAPTCHA's resistance to relay and automated attacks. Our results show that, if our CAPTHCA's parameters are set suitable value, a relay attack cannot be established economically and false acceptance rate with bot could be reduced to 0.01% without affecting human success rate.

Software defined networking (SDN) is a networking paradigm to provide automated network management at run time through network orchestration and virtualization. SDN can also enhance system resilience through recovery from failures and maintaining critical operations during cyber attacks. SDN's self-healing mechanisms can be leveraged to realized autonomous attack containment, which dynamically modifies access control rules based on configurable trust levels. In this paper, we present an approach to aid in selection of security countermeasures dynamically in an SDN enabled Energy Delivery System (EDS) and achieving tradeoff between providing security and QoS. We present the modeling of security cost based on end-to-end packet delay and throughput. We propose a non-dominated sorting based multi-objective optimization framework which can be implemented within an SDN controller to address the joint problem of optimizing between security and QoS parameters by alleviating time complexity at O(M N2), where M is the number of objective functions and N is the number of population for each generation respectively. We present simulation results which illustrate how data availability and data integrity can be achieved while maintaining QoS constraints.

The outsourcing for fabrication introduces security threats, namely hardware Trojans (HTs). Many design-for-trust (DFT) techniques have been proposed to address such threats. However, many HT detection techniques are not effective due to the dependence on golden chips, limitation of useful information available and process variations. In this paper, we data-mine on path delay information and propose a variation-tolerant path delay order encoding technique to detect HTs.