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2020-09-08
Perello, Jordi, Lopez, Albert, Careglio, Davide.  2019.  Experimenting with Real Application-specific QoS Guarantees in a Large-scale RINA Demonstrator. 2019 22nd Conference on Innovation in Clouds, Internet and Networks and Workshops (ICIN). :31–36.
This paper reports the definition, setup and obtained results of the Fed4FIRE + medium experiment ERASER, aimed to evaluate the actual Quality of Service (QoS) guarantees that the clean-slate Recursive InterNetwork Architecture (RINA) can deliver to heterogeneous applications at large-scale. To this goal, a 37-Node 5G metro/regional RINA network scenario, spanning from the end-user to the server where applications run in a datacenter has been configured in the Virtual Wall experimentation facility. This scenario has initially been loaded with synthetic application traffic flows, with diverse QoS requirements, thus reproducing different network load conditions. Next,their experienced QoS metrics end-to-end have been measured with two different QTA-Mux (i.e., the most accepted candidate scheduling policy for providing RINA with its QoS support) deployment scenarios. Moreover, on this RINA network scenario loaded with synthetic application traffic flows, a real HD (1080p) video streaming demonstration has also been conducted, setting up video streaming sessions to end-users at different network locations, illustrating the perceived Quality of Experience (QoE). Obtained results in ERASER disclose that, by appropriately deploying and configuring QTA-Mux, RINA can yield effective QoS support, which has provided perfect QoE in almost all locations in our demo when assigning video traffic flows the highest (i.e., Gold) QoS Cube.
El Abbadi, Reda, Jamouli, Hicham.  2019.  Stabilization of Cyber Physical System exposed to a random replay attack modeled by Markov chains. 2019 6th International Conference on Control, Decision and Information Technologies (CoDIT). :528–533.
This paper is concerned with the stabilization problem of cyber physical system (CPS) exposed to a random replay attack. The study will ignore the effects of communication delays and packet losses, and the attention will be focused on the effect of replay attack on the stability of (CPS). The closed-loop system is modeled as Markovian jump linear system with two jumping parameters. Linear matrix inequality (LMI) formulation is used to give a condition for stochastic stabilization of the system. Finally the theory is illustrated through a numerical example.
2020-09-04
Walck, Matthew, Wang, Ke, Kim, Hyong S..  2019.  TendrilStaller: Block Delay Attack in Bitcoin. 2019 IEEE International Conference on Blockchain (Blockchain). :1—9.
We present TendrilStaller, an eclipse attack targeting at Bitcoin's peer-to-peer network. TendrilStaller enables an adversary to delay block propagation to a victim for 10 minutes. The adversary thus impedes the victim from getting the latest blockchain state. It only takes as few as one Bitcoin full node and two light weight nodes to perform the attack. The light weight nodes perform a subset of the functions of a full Bitcoin node. The attack exploits a recent block propagation protocol introduced in April 2016. The protocol prescribes a Bitcoin node to select 3 neighbors that can send new blocks unsolicited. These neighbors are selected based on their recent performance in providing blocks quickly. The adversary induces the victim to select 3 attack nodes by having attack nodes send valid blocks to the victim more quickly than other neighbors. For this purpose, the adversary deploys a handful of light weight nodes so that the adversary itself receives new blocks faster. The adversary then performs the attack to delay blocks propagated to the victim. We implement the attack on top of current default Bitcoin protocol We deploy the attack nodes in multiple locations around the globe and randomly select victim nodes. Depending on the round-trip time between the adversary and the victim, 50%-85% of the blocks could be delayed to the victim. We further show that the adoption of light weight nodes greatly increases the attack probability by 15% in average. Finally, we propose several countermeasures to mitigate this eclipse attack.
2020-08-13
Basyoni, Lamiaa, Erbad, Aiman, Alsabah, Mashael, Fetais, Noora, Guizani, Mohsen.  2019.  Empirical Performance Evaluation of QUIC Protocol for Tor Anonymity Network. 2019 15th International Wireless Communications Mobile Computing Conference (IWCMC). :635—642.
Tor's anonymity network is one of the most widely used anonymity networks online, it consists of thousands of routers run by volunteers. Tor preserves the anonymity of its users by relaying the traffic through a number of routers (called onion routers) forming a circuit. The current design of Tor's transport layer suffers from a number of problems affecting the performance of the network. Several researches proposed changes in the transport design in order to eliminate the effect of these problems and improve the performance of Tor's network. In this paper. we propose "QuicTor", an improvement to the transport layer of Tor's network by using Google's protocol "QUIC" instead of TCP. QUIC was mainly developed to eliminate TCP's latency introduced from the handshaking delays and the head-of-line blocking problem. We provide an empirical evaluation of our proposed design and compare it to two other proposed designs, IMUX and PCTCP. We show that QuicTor significantly enhances the performance of Tor's network.
2020-08-07
Lou, Xin, Tran, Cuong, Yau, David K.Y., Tan, Rui, Ng, Hongwei, Fu, Tom Zhengjia, Winslett, Marianne.  2019.  Learning-Based Time Delay Attack Characterization for Cyber-Physical Systems. 2019 IEEE International Conference on Communications, Control, and Computing Technologies for Smart Grids (SmartGridComm). :1—6.
The cyber-physical systems (CPSes) rely on computing and control techniques to achieve system safety and reliability. However, recent attacks show that these techniques are vulnerable once the cyber-attackers have bypassed air gaps. The attacks may cause service disruptions or even physical damages. This paper designs the built-in attack characterization scheme for one general type of cyber-attacks in CPS, which we call time delay attack, that delays the transmission of the system control commands. We use the recurrent neural networks in deep learning to estimate the delay values from the input trace. Specifically, to deal with the long time-sequence data, we design the deep learning model using stacked bidirectional long short-term memory (LSTM) units. The proposed approach is tested by using the data generated from a power plant control system. The results show that the LSTM-based deep learning approach can work well based on data traces from three sensor measurements, i.e., temperature, pressure, and power generation, in the power plant control system. Moreover, we show that the proposed approach outperforms the base approach based on k-nearest neighbors.
2020-07-20
Tanksale, Vinayak.  2019.  Intrusion Detection For Controller Area Network Using Support Vector Machines. 2019 IEEE 16th International Conference on Mobile Ad Hoc and Sensor Systems Workshops (MASSW). :121–126.
Controller Area Network is the most widely adopted communication standard in automobiles. The CAN protocol is robust and is designed to minimize overhead. The light-weight nature of this protocol implies that it can't efficiently process secure communication. With the exponential increase in automobile communications, there is an urgent need for efficient and effective security countermeasures. We propose a support vector machine based intrusion detection system that is able to detect anomalous behavior with high accuracy. We outline a process for parameter selection and feature vector selection. We identify strengths and weaknesses of our system and propose to extend our work for time-series based data.
Stroup, Ronald L., Niewoehner, Kevin R..  2019.  Application of Artificial Intelligence in the National Airspace System – A Primer. 2019 Integrated Communications, Navigation and Surveillance Conference (ICNS). :1–14.

The National Airspace System (NAS), as a portion of the US' transportation system, has not yet begun to model or adopt integration of Artificial Intelligence (AI) technology. However, users of the NAS, i.e., Air transport operators, UAS operators, etc. are beginning to use this technology throughout their operations. At issue within the broader aviation marketplace, is the continued search for a solution set to the persistent daily delays and schedule perturbations that occur within the NAS. Despite billions invested through the NAS Modernization Program, the delays persist in the face of reduced demand for commercial routings. Every delay represents an economic loss to commercial transport operators, passengers, freighters, and any business depending on the transportation performance. Therefore, the FAA needs to begin to address from an advanced concepts perspective, what this wave of new technology will affect as it is brought to bear on various operations performance parameters, including safety, security, efficiency, and resiliency solution sets. This paper is the first in a series of papers we are developing to explore the application of AI in the National Airspace System (NAS). This first paper is meant to get everyone in the aviation community on the same page, a primer if you will, to start the technical discussions. This paper will define AI; the capabilities associated with AI; current use cases within the aviation ecosystem; and how to prepare for insertion of AI in the NAS. The next series of papers will look at NAS Operations Theory utilizing AI capabilities and eventually leading to a future intelligent NAS (iNAS) environment.

2020-07-10
Reshmi, T S, Daniel Madan Raja, S.  2019.  A Review on Self Destructing Data:Solution for Privacy Risks in OSNs. 2019 5th International Conference on Advanced Computing Communication Systems (ICACCS). :231—235.

Online Social Networks(OSN) plays a vital role in our day to day life. The most popular social network, Facebook alone counts currently 2.23 billion users worldwide. Online social network users are aware of the various security risks that exist in this scenario including privacy violations and they are utilizing the privacy settings provided by OSN providers to make their data safe. But most of them are unaware of the risk which exists after deletion of their data which is not really getting deleted from the OSN server. Self destruction of data is one of the prime recommended methods to achieve assured deletion of data. Numerous techniques have been developed for self destruction of data and this paper discusses and evaluates these techniques along with the various privacy risks faced by an OSN user in this web centered world.

2020-06-19
Garrido, Pablo, Sanchez, Isabel, Ferlin, Simone, Aguero, Ramon, Alay, Ozgu.  2019.  Poster: rQUIC - integrating FEC with QUIC for robust wireless communications. 2019 IFIP Networking Conference (IFIP Networking). :1—2.

Quick UDP Internet Connections (QUIC) is an experimental transport protocol designed to primarily reduce connection establishment and transport latency, as well as to improve security standards with default end-to-end encryption in HTTPbased applications. QUIC is a multiplexed and secure transport protocol fostered by Google and its design emerged from the urgent need of innovation in the transport layer, mainly due to difficulties extending TCP and deploying new protocols. While still under standardisation, a non-negligble fraction of the Internet's traffic, more than 7% of a European Tier1-ISP, is already running over QUIC and it constitutes more than 30% of Google's egress traffic [1].

2020-06-08
Hu, Qin, Wang, Shengling, Cheng, Xiuzhen.  2019.  A Game Theoretic Analysis on Block Withholding Attacks Using the Zero-Determinant Strategy. 2019 IEEE/ACM 27th International Symposium on Quality of Service (IWQoS). :1–10.
In Bitcoin's incentive system that supports open mining pools, block withholding attacks incur huge security threats. In this paper, we investigate the mutual attacks among pools as this determines the macroscopic utility of the whole distributed system. Existing studies on pools' interactive attacks usually employ the conventional game theory, where the strategies of the players are considered pure and equal, neglecting the existence of powerful strategies and the corresponding favorable game results. In this study, we take advantage of the Zero-Determinant (ZD) strategy to analyze the block withholding attack between any two pools, where the ZD adopter has the unilateral control on the expected payoffs of its opponent and itself. In this case, we are faced with the following questions: who can adopt the ZD strategy? individually or simultaneously? what can the ZD player achieve? In order to answer these questions, we derive the conditions under which two pools can individually or simultaneously employ the ZD strategy and demonstrate the effectiveness. To the best of our knowledge, we are the first to use the ZD strategy to analyze the block withholding attack among pools.
2020-06-02
Aliasgari, Malihe, Simeone, Osvaldo, Kliewer, Jörg.  2019.  Distributed and Private Coded Matrix Computation with Flexible Communication Load. 2019 IEEE International Symposium on Information Theory (ISIT). :1092—1096.

Tensor operations, such as matrix multiplication, are central to large-scale machine learning applications. These operations can be carried out on a distributed computing platform with a master server at the user side and multiple workers in the cloud operating in parallel. For distributed platforms, it has been recently shown that coding over the input data matrices can reduce the computational delay, yielding a tradeoff between recovery threshold and communication load. In this work, we impose an additional security constraint on the data matrices and assume that workers can collude to eavesdrop on the content of these data matrices. Specifically, we introduce a novel class of secure codes, referred to as secure generalized PolyDot codes, that generalizes previously published non-secure versions of these codes for matrix multiplication. These codes extend the state-of-the-art by allowing a flexible trade-off between recovery threshold and communication load for a fixed maximum number of colluding workers.

2020-06-01
Kapoor, Chavi.  2019.  Routing Table Management using Dynamic Information with Routing Around Connectivity Holes (RACH) for IoT Networks. 2019 International Conference on Automation, Computational and Technology Management (ICACTM). :174—177.

The internet of things (IoT) is the popular wireless network for data collection applications. The IoT networks are deployed in dense or sparse architectures, out of which the dense networks are vastly popular as these are capable of gathering the huge volumes of data. The collected data is analyzed using the historical or continuous analytical systems, which uses the back testing or time-series analytics to observe the desired patterns from the target data. The lost or bad interval data always carries the high probability to misguide the analysis reports. The data is lost due to a variety of reasons, out of which the most popular ones are associated with the node failures and connectivity holes, which occurs due to physical damage, software malfunctioning, blackhole/wormhole attacks, route poisoning, etc. In this paper, the work is carried on the new routing scheme for the IoTs to avoid the connectivity holes, which analyzes the activity of wireless nodes and takes the appropriate actions when required.

Talusan, Jose Paolo, Tiausas, Francis, Yasumoto, Keiichi, Wilbur, Michael, Pettet, Geoffrey, Dubey, Abhishek, Bhattacharjee, Shameek.  2019.  Smart Transportation Delay and Resiliency Testbed Based on Information Flow of Things Middleware. 2019 IEEE International Conference on Smart Computing (SMARTCOMP). :13–18.
Edge and Fog computing paradigms are used to process big data generated by the increasing number of IoT devices. These paradigms have enabled cities to become smarter in various aspects via real-time data-driven applications. While these have addressed some flaws of cloud computing some challenges remain particularly in terms of privacy and security. We create a testbed based on a distributed processing platform called the Information flow of Things (IFoT) middleware. We briefly describe a decentralized traffic speed query and routing service implemented on this framework testbed. We configure the testbed to test countermeasure systems that aim to address the security challenges faced by prior paradigms. Using this testbed, we investigate a novel decentralized anomaly detection approach for time-sensitive distributed smart transportation systems.
2020-05-29
Khelifi, Hakima, Luo, Senlin, Nour, Boubakr, Moungla, Hassine.  2019.  A QoS-Aware Cache Replacement Policy for Vehicular Named Data Networks. 2019 IEEE Global Communications Conference (GLOBECOM). :1—6.

Vehicular Named Data Network (VNDN) uses Named Data Network (NDN) as a communication enabler. The communication is achieved using the content name instead of the host address. NDN integrates content caching at the network level rather than the application level. Hence, the network becomes aware of content caching and delivering. The content caching is a fundamental element in VNDN communication. However, due to the limitations of the cache store, only the most used content should be cached while the less used should be evicted. Traditional caching replacement policies may not work efficiently in VNDN due to the large and diverse exchanged content. To solve this issue, we propose an efficient cache replacement policy that takes the quality of service into consideration. The idea consists of classifying the traffic into different classes, and split the cache store into a set of sub-cache stores according to the defined traffic classes with different storage capacities according to the network requirements. Each content is assigned a popularity-density value that balances the content popularity with its size. Content with the highest popularity-density value is cached while the lowest is evicted. Simulation results prove the efficiency of the proposed solution to enhance the overall network quality of service.

Yao, Lin, Jiang, Binyao, Deng, Jing, Obaidat, Mohammad S..  2019.  LSTM-Based Detection for Timing Attacks in Named Data Network. 2019 IEEE Global Communications Conference (GLOBECOM). :1—6.

Named Data Network (NDN) is an alternative to host-centric networking exemplified by today's Internet. One key feature of NDN is in-network caching that reduces access delay and query overhead by caching popular contents at the source as well as at a few other nodes. Unfortunately, in-network caching suffers various privacy risks by different attacks, one of which is termed timing attack. This is an attack to infer whether a consumer has recently requested certain contents based on the time difference between the delivery time of those contents that are currently cached and those that are not cached. In order to prevent the privacy leakage and resist such kind of attacks, we propose a detection scheme by adopting Long Short-term Memory (LSTM) model. Based on the four input features of LSTM, cache hit ratio, average request interval, request frequency, and types of requested contents, we timely capture more important eigenvalues by dividing a constant time window size into a few small slices in order to detect timing attacks accurately. We have performed extensive simulations to compare our scheme with several other state-of-the-art schemes in classification accuracy, detection ratio, false alarm ratio, and F-measure. It has been shown that our scheme possesses a better performance in all cases studied.

2020-05-26
Hamamreh, Rushdi A., Ayyad, Mohammad, Jamoos, Mohammad.  2019.  RAD: Reinforcement Authentication DYMO Protocol for MANET. 2019 International Conference on Promising Electronic Technologies (ICPET). :136–141.
Mobile ad hoc network (MANET) does not have fixed infrastructure centralized server which manage the connections between the nodes. Rather, the nodes in MANET move randomly. Thus, it is risky to exchange data between nodes because there is a high possibility of having malicious node in the path. In this paper, we will describe a new authentication technique using message digest 5 (MD5), hashing for dynamic MANET on demand protocol (DYMO) based on reinforcement learning. In addition, we will describe an encryption technique that can be used without the need for a third party to distribute a secret key. After implementing the suggested model, results showed a remarkable enhancement in securing the path by increasing the packet delivery ratio and average throughput. On the other hand, there was an increase in end to end delay due to time spent in cryptographic operations.
Tripathi, Shripriya.  2019.  Performance Analysis of AODV and DSR Routing Protocols of MANET under Wormhole Attack and a Suggested Trust Based Routing Algorithm for DSR. 2019 IEEE International WIE Conference on Electrical and Computer Engineering (WIECON-ECE). :1–5.

The nodes in Mobile Ad hoc Network (MANET) can self-assemble themselves, locomote unreservedly and can interact with one another without taking any help from a centralized authority or fixed infrastructure. Due to its continuously changing and self-organizing nature, MANET is vulnerable to a variety of attacks like spoofing attack, wormhole attack, black hole attack, etc. This paper compares and analyzes the repercussion of the wormhole attack on MANET's two common routing protocols of reactive category, specifically, Dynamic Source Routing (DSR) and Ad-hoc On-Demand Distance Vector (AODV) by increasing the number of wormhole tunnels in MANET. The results received by simulation will reveal that DSR is greatly affected by this attack. So, as a solution, a routing algorithm for DSR which is based on trust is proposed to prevent the routes from caching malicious nodes.

Fu, Yulong, Li, Guoquan, Mohammed, Atiquzzaman, Yan, Zheng, Cao, Jin, Li, Hui.  2019.  A Study and Enhancement to the Security of MANET AODV Protocol Against Black Hole Attacks. 2019 IEEE SmartWorld, Ubiquitous Intelligence Computing, Advanced Trusted Computing, Scalable Computing Communications, Cloud Big Data Computing, Internet of People and Smart City Innovation (SmartWorld/SCALCOM/UIC/ATC/CBDCom/IOP/SCI). :1431–1436.
Mobile AdHoc Networks (MANET) can be fast implemented, and it is very popular in many specific network requirements, such as UAV (Unmanned Aerial Unit), Disaster Recovery and IoT (Internet of Things) etc. However, MANET is also vulnerable. AODV (Ad hoc On-Demand Distance Vector Routing) protocol is one type of MANET routing protocol and many attacks can be implemented to break the connections on AODV based AdHoc networks. In this article, aim of protecting the MANET security, we modeled the AODV protocol with one type of Automata and analyzed the security vulnerabilities of it; then based on the analyzing results, we proposed an enhancement to AODV protocol to against the Black Hole Attacks. We also implemented the proposed enhancement in NS3 simulator and verified the correctness, usability and efficiency.
Kumari, Alpana, Krishnan, Shoba.  2018.  Simulation Based Study of Blackhole Attack Under AODV Protocol. 2018 Fourth International Conference on Computing Communication Control and Automation (ICCUBEA). :1–6.
Mobile adhoc network are fully autonomous where the nodes act both as node as well as router. Centralization is absent in MANETs. In MANETs nodes are continuously moving and have an open access which put it at a risk of large number of attacks. Security in such networks is therefore a critical matter. In order to find solution to this issue various attacks need to be studied and analyzed. In Blackhole attack, the unauthorized node in the path of source and target nodes takes away the packets sent by the source and drops them by not heading them towards the target node. The malicious behavior launched by Blackhole attack deteriorates the network performance.
Sbai, Oussama, Elboukhari, Mohamed.  2018.  Simulation of MANET's Single and Multiple Blackhole Attack with NS-3. 2018 IEEE 5th International Congress on Information Science and Technology (CiSt). :612–617.
Mobile Ad-hoc Networks (MANETs) have gained popularity both in research and in industrial fields. This is due to their ad hoc nature, easy deployment thanks to the lack of fixed infrastructure, self-organization of its components, dynamic topologies and the absence of any central authority for routing. However, MANETs suffer from several vulnerabilities such as battery power, limited memory space, and physical protection of network nodes. In addition, MANETs are sensitive to various attacks that threaten network security like Blackhole attack in its different implementation (single and multiple). In this article, we present the simulation results of single and multiple Blackhole attack in AODV and OLSR protocols on using NS-3.27 simulator. In this simulation, we took into consideration the density of the network described by the number of nodes included in the network, the speed of the nodes, the mobility model and even we chose the IEEE 802.11ac protocol for the pbysicallayer, in order to have a simulation, which deals with more general and more real scenarios. To be able to evaluate the impact of the attack on the network, the Packet delivery rate, Routing overhead, Throughput and Average End to End delay have been chosen as metrics for performance evaluation.
2020-05-15
Khorsandroo, Sajad, Tosun, Ali Saman.  2018.  Time Inference Attacks on Software Defined Networks: Challenges and Countermeasures. 2018 IEEE 11th International Conference on Cloud Computing (CLOUD). :342—349.

Through time inference attacks, adversaries fingerprint SDN controllers, estimate switches flow-table size, and perform flow state reconnaissance. In fact, timing a SDN and analyzing its results can expose information which later empowers SDN resource-consumption or saturation attacks. In the real world, however, launching such attacks is not easy. This is due to some challenges attackers may encounter while attacking an actual SDN deployment. These challenges, which are not addressed adequately in the related literature, are investigated in this paper. Accordingly, practical solutions to mitigate such attacks are also proposed. Discussed challenges are clarified by means of conducting extensive experiments on an actual cloud data center testbed. Moreover, mitigation schemes have been implemented and examined in details. Experimental results show that proposed countermeasures effectively block time inference attacks.

Fraunholz, Daniel, Schotten, Hans D..  2018.  Defending Web Servers with Feints, Distraction and Obfuscation. 2018 International Conference on Computing, Networking and Communications (ICNC). :21—25.

In this paper we investigate deceptive defense strategies for web servers. Web servers are widely exploited resources in the modern cyber threat landscape. Often these servers are exposed in the Internet and accessible for a broad range of valid as well as malicious users. Common security strategies like firewalls are not sufficient to protect web servers. Deception based Information Security enables a large set of counter measures to decrease the efficiency of intrusions. In this work we depict several techniques out of the reconnaissance process of an attacker. We match these with deceptive counter measures. All proposed measures are implemented in an experimental web server with deceptive counter measure abilities. We also conducted an experiment with honeytokens and evaluated delay strategies against automated scanner tools.

Chekired, Djabir Abdeldjalil, Khoukhi, Lyes.  2019.  Distributed SDN-Based C4ISR Communications: A Delay-Tolerant Network for Trusted Tactical Cloudlets. 2019 International Conference on Military Communications and Information Systems (ICMCIS). :1—7.

The next generation military environment requires a delay-tolerant network for sharing data and resources using an interoperable computerized, Command, Control, Communications, Intelligence, Surveillance and Reconnaissance (C4ISR) infrastructure. In this paper, we propose a new distributed SDN (Software-Defined Networks) architecture for tactical environments based on distributed cloudlets. The objective is to reduce the end-to-end delay of tactical traffic flow, and improve management capabilities, allowing flexible control and network resource allocation. The proposed SDN architecture is implemented over three layers: decentralized cloudlets layer where each cloudlet has its SDRN (Software-Defined Radio Networking) controller, decentralized MEC (Mobile Edge Computing) layer with an SDN controller for each MEC, and a centralized private cloud as a trusted third-part authority controlled by a centralized SDN controller. The experimental validations are done via relevant and realistic tactical scenarios based on strategic traffics loads, i.e., Tactical SMS (Short Message Service), UVs (Unmanned Vehicle) patrol deployment and high bite rate ISR (Intelligence, Surveillance, and Reconnaissance) video.

2020-05-11
Xue, Kaiping, Zhang, Xiang, Xia, Qiudong, Wei, David S.L., Yue, Hao, Wu, Feng.  2018.  SEAF: A Secure, Efficient and Accountable Access Control Framework for Information Centric Networking. IEEE INFOCOM 2018 - IEEE Conference on Computer Communications. :2213–2221.
Information Centric Networking (ICN) has been regarded as an ideal architecture for the next-generation network to handle users' increasing demand for content delivery with in-network cache. While making better use of network resources and providing better delivery service, an effective access control mechanism is needed due to wide dissemination of contents. However, in the existing solutions, making cache-enabled routers or content providers authenticate users' requests causes high computation overhead and unnecessary delay. Also, straightforward utilization of advanced encryption algorithms increases the opportunities for DoS attacks. Besides, privacy protection and service accountability are rarely taken into account in this scenario. In this paper, we propose a secure, efficient, and accountable access control framework, called SEAF, for ICN, in which authentication is performed at the network edge to block unauthorized requests at the very beginning. We adopt group signature to achieve anonymous authentication, and use hash chain technique to greatly reduce the overhead when users make continuous requests for the same file. Furthermore, the content providers can affirm the service amount received from the network and extract feedback information from the signatures and hash chains. By formal security analysis and the comparison with related works, we show that SEAF achieves the expected security goals and possesses more useful features. The experimental results also demonstrate that our design is efficient for routers and content providers, and introduces only slight delay for users' content retrieval.
2020-04-24
Bellec, Q., le Claire, J.C., Benkhoris, M.F., Coulibaly, P..  2019.  Investigation of time delay effects on the current in a power converter regulated by Phase-Shift Self-Oscillating Current Controller. 2019 21st European Conference on Power Electronics and Applications (EPE '19 ECCE Europe). :P.1–P.10.

This paper deals with effects of current sensor bandwidth and time delays in a system controlled by a Phase-Shift Self-Oscillating Current Controller (PSSOCC). The robustness of this current controller has been proved in former works showing its good performances in a large range of applications including AC/DC and DC/AC converters, power factor correction, active filters, isolation amplifiers and motor control. As switching frequencies can be upper than 30kHz, time delays and bandwidth limitations cannot be neglected in comparison with former works on this robust current controller. Thus, several models are proposed in this paper to analyze system behaviours. Those models permit to find analytical expressions binding maximum oscillation frequency with time delay and/or additional filter parameters. Through current spectrums analysis, quality of analytical expressions is proved for each model presented in this work. An experimental approach shows that every element of the electronic board having a low-pass effect or delaying command signals need to be included in the model in order to have a perfect match between calculations, simulations and practical results.