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Xiang Ji

Bio: Xiang Ji is an academic researcher from East China University of Science and Technology. The author has contributed to research in topics: Test case & Cluster analysis. The author has an hindex of 5, co-authored 7 publications receiving 109 citations.

Papers
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Proceedings ArticleDOI
01 Dec 2016
TL;DR: A novel SDN-based geographic routing protocol for VANET, based on node location, vehicles density and digital map is proposed, which performs much better than related routing protocols in terms of both packet delivery ratio and delivery delay time.
Abstract: Vehicular Ad hoc Network (VANET) is a new technology that integrates the potentials of next generation wireless networks into vehicles. The design of routing protocols in VANETs is crucial in supporting the Intelligent Transportation Systems (ITS). Typical geographic routings only use local information to make routing decisions which may lead to local maximum and sparse connectivity problems. This paper proposes a novel SDN-based geographic routing (SDGR) protocol for VANET, based on node location, vehicles density and digital map. Software-Defined Networking (SDN) is used to decouple the network management from data transferring. In SDGR, the central controller gathers information of vehicles and provides a global view to compute the optimal routing paths. Simulation results show that the proposed scheme performs much better than related routing protocols in terms of both packet delivery ratio and delivery delay time.

58 citations

Journal ArticleDOI
TL;DR: A link reliability-based clustering algorithm (LRCA) to provide efficient and reliable data transmission in VANETs and a routing protocol of LRCA to serve the infotainment applications in VIANET is proposed.
Abstract: Vehicular ad hoc network (VANET) is an emerging technology for the future intelligent transportation systems (ITSs). The current researches are intensely focusing on the problems of routing protocol reliability and scalability across the urban VANETs. Vehicle clustering is testified to be a promising approach to improve routing reliability and scalability by grouping vehicles together to serve as the foundation for ITS applications. However, some prominent characteristics, like high mobility and uneven spatial distribution of vehicles, may affect the clustering performance. Therefore, how to establish and maintain stable clusters has become a challenging problem in VANETs. This paper proposes a link reliability-based clustering algorithm (LRCA) to provide efficient and reliable data transmission in VANETs. Before clustering, a novel link lifetime-based (LLT-based) neighbor sampling strategy is put forward to filter out the redundant unstable neighbors. The proposed clustering scheme mainly composes of three parts: cluster head selection, cluster formation, and cluster maintenance. Furthermore, we propose a routing protocol of LRCA to serve the infotainment applications in VANET. To make routing decisions appropriate, we nominate special nodes at intersections to evaluate the network condition by assigning weights to the road segments. Routes with the lowest weights are then selected as the optimal data forwarding paths. We evaluate clustering stability and routing performance of the proposed approach by comparing with some existing schemes. The extensive simulation results show that our approach outperforms in both cluster stability and data transmission.

36 citations

Proceedings ArticleDOI
01 May 2016
TL;DR: The effectiveness of the proposed approach is evaluated by a set of metrics like probability of success, attack and defense cost and the impact of an attack, and two economic factors (ROA and ROI) are introduced to evaluate the performance of ADTree.
Abstract: Cyber-physical system (CPS) is the fuse of cyber world and the dynamic physical world and it is being widely used in areas closely related to people's livelihood. Therefore, the security issues of CPS have drawn a global attention and an appropriate risk assessment for CPS is in urgent need. The existing proposals using attack trees for risk assessment mainly focus on depicting the possible intrusions, not for interactions between threats and defenses. In this paper, a risk assessment idea for cyber-physical system with the use of attack-defense tree (ADTree) is proposed, considering the effect of both the attack cost and defense cost. The effectiveness of the proposed approach is evaluated by a set of metrics like probability of success, attack and defense cost and the impact of an attack. In addition, we introduce two economic factors (ROA and ROI) to evaluate the performance of ADTree. Finally, an illustration case of threat risk analysis in SCADA system is given to demonstrate our approach. Overall, our approach provides an effective means of risk assessment and countermeasures evaluation in the evolutional process of security management for cyber-physical system security.

26 citations

Proceedings ArticleDOI
Wenhao Fu, Huiqun Yu, Guisheng Fan, Xiang Ji, Xin Pei 
01 Nov 2017
TL;DR: This approach extracts the high suspicious statements in the faulty program and removes the coincidental passed test cases for test suite selection, and determines the final composition of each similar test set based on the contribution of failed test cases to fault localization.
Abstract: In order to improve the effectiveness of fault localization, various test suite reduction techniques have been proposed. However, excessive or improper reduction of test cases may lose some testing information, thus causing a negative impact on fault localization. In this paper, we propose a new similarity-based test suite reduction approach to improving spectrum-based fault localization. Firstly, this approach extracts the high suspicious statements in the faulty program and removes the coincidental passed test cases for test suite selection. Then, it selects similar passed test cases for each different failed test case from the new passed test set based on the similar proportion of their execution traces, and determines the final composition of each similar test set based on the contribution of failed test cases to fault localization. By using the execution information of each similar test set with a spectrum-based fault localization approach, the ranks of statements can be obtained. Finally, synthesizing all ranks of statements in each rank list, we obtain the final rank list of statements. Several experiments show that our approach can help reduce the debugging effort in terms of the percentage of statements needed to be inspected when locating faults in both single-fault and multi-fault programs. Moreover, the results demonstrate that the value of similar proportion have nontrivial influence on the effectiveness of fault localization.

8 citations

Proceedings ArticleDOI
01 Dec 2017
TL;DR: A new test case prioritization algorithm based on program changes and method (function) invocation relationship is proposed that reduces the prioritization problem to an integer linear programming (ILP) problem, and finally prioritizes test cases according to their fault detection capabilities.
Abstract: Regression testing is essential for assuring the quality of a software product. Because rerunning all test cases in regression testing may be impractical under limited resources, test case prioritization is a feasible solution to optimize regression testing by reordering test cases for the current testing version. In this paper, we propose a new test case prioritization algorithm based on program changes and method (function) invocation relationship. Combining the estimated risk value of each program method (function) and the method (function) coverage information, the fault detection capability of each test case can be calculated. The algorithm reduces the prioritization problem to an integer linear programming (ILP) problem, and finally prioritizes test cases according to their fault detection capabilities. Experiments are conducted on 11 programs to validate the effectiveness of our proposed algorithm. Experimental results show that our approach is more effective than some well studied test case prioritization techniques in terms of average percentage of fault detected (APFD) values.

8 citations


Cited by
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Journal ArticleDOI
TL;DR: This review examines and classify the current test case prioritization approaches in TCP based on the articulated research questions and found that variations in the starting point of TCP process among the approaches provide a different timeline and benefit to project manager to choose which approaches suite with the project schedule and available resources.
Abstract: Context Software quality can be assured by going through software testing process. However, software testing phase is an expensive process as it consumes a longer time. By scheduling test cases execution order through a prioritization approach, software testing efficiency can be improved especially during regression testing. Objective It is a notable step to be taken in constructing important software testing environment so that a system's commercial value can increase. The main idea of this review is to examine and classify the current test case prioritization approaches based on the articulated research questions. Method Set of search keywords with appropriate repositories were utilized to extract most important studies that fulfill all the criteria defined and classified under journal, conference paper, symposiums and workshops categories. 69 primary studies were nominated from the review strategy. Results There were 40 journal articles, 21 conference papers, three workshop articles, and five symposium articles collected from the primary studies. As for the result, it can be said that TCP approaches are still broadly open for improvements. Each approach in TCP has specified potential values, advantages, and limitation. Additionally, we found that variations in the starting point of TCP process among the approaches provide a different timeline and benefit to project manager to choose which approaches suite with the project schedule and available resources. Conclusion Test case prioritization has already been considerably discussed in the software testing domain. However, it is commonly learned that there are quite a number of existing prioritization techniques that can still be improved especially in data used and execution process for each approach.

151 citations

Journal ArticleDOI
TL;DR: This study presents an exhaustive review of previous works by classifying them based on based on wireless communication, particularly VANET, and highlights the current and emerging technologies with use cases in vehicular networks to address the several challenges in the VANet infrastructure.
Abstract: Vehicular communication networks is a powerful tool that enables numerous vehicular data services and applications. The rapid growth in vehicles has also resulted in the vehicular network becoming heterogeneous, dynamic, and large-scale, making it hard to meet the strict requirements, such as extremely latency, high mobility, top security, and enormous connections of the fifth-generation network. Previous studies have shown that with the increase in the application of Software-Defined Networking (SDN) on Vehicular Ad-hoc Network (VANET) in industries, researchers have exerted considerable efforts to improve vehicular communications. This study presents an exhaustive review of previous works by classifying them based on based on wireless communication, particularly VANET. First, a concise summary of the VANET structure and SDN controller with layers and details of their infrastructure is provided. Second, a description of SDN-VANET applications in different wireless communications, such as the Internet of Things (IoT) and VANET is provided with concentration on the examination and comparison of SDN-VANET works on several parameters. This paper also provides a detailed analysis of the open issues and research directions accomplished while integrating the VANET with SDN. It also highlights the current and emerging technologies with use cases in vehicular networks to address the several challenges in the VANET infrastructure. This survey acts as a catalyst in raising the emergent robustness routing protocol, latency, connectivity and security issues of future SDN-VANET architectures.

120 citations

Journal ArticleDOI
TL;DR: Examining and classifying a number of related SDN- based research works on wireless networks specially VANETs and a review of current research initiatives to solve challenges of vehicular environment is presented.

84 citations

Journal ArticleDOI
TL;DR: A compilation of the work on the SDN‐based VANET system as a whole, incorporating its architecture, use‐cases, and opportunities, is still inadequate and the taxonomy of SDVN is presented based on the architecture modes, protocols, access technologies and opportunities with trending technologies.

83 citations

Journal ArticleDOI
TL;DR: The SMS provides the state of the art in MBSE4CPS, but also points out several open issues that would deserve more investigation, e.g., the lack of engineering security solutions for CPSs, limited tool support, too few industrial case studies, and the challenge of bridging DSLs in engineering secure CPSs.
Abstract: ContextCyber-physical systems (CPSs) have emerged to be the next generation of engineered systems driving the so-called fourth industrial revolution. CPSs are becoming more complex, open and more prone to security threats, which urges security to be engineered systematically into CPSs. Model-Based Security Engineering (MBSE) could be a key means to tackle this challenge via security by design, abstraction, and automation. ObjectiveWe aim at providing an initial assessment of the state of the art in MBSE for CPSs (MBSE4CPS). Specifically, this work focuses on finding out 1) the publication statistics of MBSE4CPS studies; 2) the characteristics of MBSE4CPS studies; and 3) the open issues of MBSE4CPS research. MethodWe conducted a systematic mapping study (SMS) following a rigorous protocol that was developed based on the state-of-the-art SMS and systematic review guidelines. From thousands of relevant publications, we systematically identified 48 primary MBSE4CPS studies for data extraction and synthesis to answer predefined research questions. ResultsSMS results show that for three recent years (2014-2016) the number of primary MBSE4CPS studies has increased significantly. Within the primary studies, the popularity of using Domain-Specific Languages (DSLs) is comparable with the use of the standardised UML modelling notation. Most primary studies do not explicitly address specific security concerns (e.g., confidentiality, integrity) but rather focus on security analyses in general on threats, attacks or vulnerabilities. Few primary studies propose to engineer security solutions for CPSs. Many focus on the early stages of development lifecycle such as security requirement engineering or analysis. ConclusionThe SMS does not only provide the state of the art in MBSE4CPS, but also points out several open issues that would deserve more investigation, e.g., the lack of engineering security solutions for CPSs, limited tool support, too few industrial case studies, and the challenge of bridging DSLs in engineering secure CPSs.

72 citations