Visible to the public Biblio

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2020-11-04
Huang, B., Zhang, P..  2018.  Software Runtime Accumulative Testing. 2018 12th International Conference on Reliability, Maintainability, and Safety (ICRMS). :218—222.

The "aging" phenomenon occurs after the long-term running of software, with the fault rate rising and running efficiency dropping. As there is no corresponding testing type for this phenomenon among conventional software tests, "software runtime accumulative testing" is proposed. Through analyzing several examples of software aging causing serious accidents, software is placed in the system environment required for running and the occurrence mechanism of software aging is analyzed. In addition, corresponding testing contents and recommended testing methods are designed with regard to all factors causing software aging, and the testing process and key points of testing requirement analysis for carrying out runtime accumulative testing are summarized, thereby providing a method and guidance for carrying out "software runtime accumulative testing" in software engineering.

2020-11-02
Ping, C., Jun-Zhe, Z..  2019.  Research on Intelligent Evaluation Method of Transient Analysis Software Function Test. 2019 International Conference on Advances in Construction Machinery and Vehicle Engineering (ICACMVE). :58–61.

In transient distributed cloud computing environment, software is vulnerable to attack, which leads to software functional completeness, so it is necessary to carry out functional testing. In order to solve the problem of high overhead and high complexity of unsupervised test methods, an intelligent evaluation method for transient analysis software function testing based on active depth learning algorithm is proposed. Firstly, the active deep learning mathematical model of transient analysis software function test is constructed by using association rule mining method, and the correlation dimension characteristics of software function failure are analyzed. Then the reliability of the software is measured by the spectral density distribution method of software functional completeness. The intelligent evaluation model of transient analysis software function testing is established in the transient distributed cloud computing environment, and the function testing and reliability intelligent evaluation are realized. Finally, the performance of the transient analysis software is verified by the simulation experiment. The results show that the accuracy of the software functional integrity positioning is high and the intelligent evaluation of the transient analysis software function testing has a good self-adaptability by using this method to carry out the function test of the transient analysis software. It ensures the safe and reliable operation of the software.

Chong, T., Anu, V., Sultana, K. Z..  2019.  Using Software Metrics for Predicting Vulnerable Code-Components: A Study on Java and Python Open Source Projects. 2019 IEEE International Conference on Computational Science and Engineering (CSE) and IEEE International Conference on Embedded and Ubiquitous Computing (EUC). :98–103.

Software vulnerabilities often remain hidden until an attacker exploits the weak/insecure code. Therefore, testing the software from a vulnerability discovery perspective becomes challenging for developers if they do not inspect their code thoroughly (which is time-consuming). We propose that vulnerability prediction using certain software metrics can support the testing process by identifying vulnerable code-components (e.g., functions, classes, etc.). Once a code-component is predicted as vulnerable, the developers can focus their testing efforts on it, thereby avoiding the time/effort required for testing the entire application. The current paper presents a study that compares how software metrics perform as vulnerability predictors for software projects developed in two different languages (Java vs Python). The goal of this research is to analyze the vulnerability prediction performance of software metrics for different programming languages. We designed and conducted experiments on security vulnerabilities reported for three Java projects (Apache Tomcat 6, Tomcat 7, Apache CXF) and two Python projects (Django and Keystone). In this paper, we focus on a specific type of code component: Functions. We apply Machine Learning models for predicting vulnerable functions. Overall results show that software metrics-based vulnerability prediction is more useful for Java projects than Python projects (i.e., software metrics when used as features were able to predict Java vulnerable functions with a higher recall and precision compared to Python vulnerable functions prediction).

2020-10-12
Brenner, Bernhard, Weippl, Edgar, Ekelhart, Andreas.  2019.  Security Related Technical Debt in the Cyber-Physical Production Systems Engineering Process. IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society. 1:3012–3017.

Technical debt is an analogy introduced in 1992 by Cunningham to help explain how intentional decisions not to follow a gold standard or best practice in order to save time or effort during creation of software can later on lead to a product of lower quality in terms of product quality itself, reliability, maintainability or extensibility. Little work has been done so far that applies this analogy to cyber physical (production) systems (CP(P)S). Also there is only little work that uses this analogy for security related issues. This work aims to fill this gap: We want to find out which security related symptoms within the field of cyber physical production systems can be traced back to TD items during all phases, from requirements and design down to maintenance and operation. This work shall support experts from the field by being a first step in exploring the relationship between not following security best practices and concrete increase of costs due to TD as consequence.

2020-09-28
Mohammadi, Mahmoud, Chu, Bill, Richter Lipford, Heather.  2019.  Automated Repair of Cross-Site Scripting Vulnerabilities through Unit Testing. 2019 IEEE International Symposium on Software Reliability Engineering Workshops (ISSREW). :370–377.
Many web applications are vulnerable to Cross Site Scripting (XSS) attacks enabling attackers to steal sensitive information and commit frauds. Much research in this area have focused on detecting vulnerable web pages using static and dynamic program analysis. The best practice to prevent XSS vulnerabilities is to encode untrusted dynamic content. However, a common programming error is the use of a wrong type of encoder to sanitize untrusted data, leaving the application vulnerable. We propose a new approach that can automatically fix this common type of XSS vulnerability in many situations. This approach is integrated into the software maintenance life cycle through unit testing. Vulnerable codes are refactored to reflect the suggested encoder and then verified using an attack evaluating mechanism to find a proper repair. Evaluation of this approach has been conducted on an open source medical record application with over 200 web pages written in JSP.
2020-07-06
Frias, Alex Davila, Yodo, Nita, Yadav, Om Prakash.  2019.  Mixed-Degradation Profiles Assessment of Critical Components in Cyber-Physical Systems. 2019 Annual Reliability and Maintainability Symposium (RAMS). :1–6.
This paper presents a general model to assess the mixed-degradation profiles of critical components in a Cyber-Physical System (CPS) based on the reliability of its critical physical and software components. In the proposed assessment, the cyber aspect of a CPS was approached from a software reliability perspective. Although extensive research has been done on physical components degradation and software reliability separately, research for the combined physical-software systems is still scarce. The non-homogeneous Poisson Processes (NHPP) software reliability models are deemed to fit well with the real data and have descriptive and predictive abilities, which could make them appropriate to estimate software components reliability. To show the feasibility of the proposed approach, a case study for mixed-degradation profiles assessment is presented with n physical components and one major software component forming a critical subsystem in CPS. Two physical components were assumed to have different degradation paths with the dependency between them. Series and parallel structures were investigated for physical components. The software component failure data was taken from a wireless network switching center and fitted into a Weibull software reliability model. The case study results revealed that mix-degradation profiles of physical components, combined with software component profile, produced a different CPS reliability profile.
2020-04-03
Jabeen, Gul, Ping, Luo.  2019.  A Unified Measurable Software Trustworthy Model Based on Vulnerability Loss Speed Index. 2019 18th IEEE International Conference On Trust, Security And Privacy In Computing And Communications/13th IEEE International Conference On Big Data Science And Engineering (TrustCom/BigDataSE). :18—25.

As trust becomes increasingly important in the software domain. Due to its complex composite concept, people face great challenges, especially in today's dynamic and constantly changing internet technology. In addition, measuring the software trustworthiness correctly and effectively plays a significant role in gaining users trust in choosing different software. In the context of security, trust is previously measured based on the vulnerability time occurrence to predict the total number of vulnerabilities or their future occurrence time. In this study, we proposed a new unified index called "loss speed index" that integrates the most important variables of software security such as vulnerability occurrence time, number and severity loss, which are used to evaluate the overall software trust measurement. Based on this new definition, a new model called software trustworthy security growth model (STSGM) has been proposed. This paper also aims at filling the gap by addressing the severity of vulnerabilities and proposed a vulnerability severity prediction model, the results are further evaluated by STSGM to estimate the future loss speed index. Our work has several features such as: (1) It is used to predict the vulnerability severity/type in future, (2) Unlike traditional evaluation methods like expert scoring, our model uses historical data to predict the future loss speed of software, (3) The loss metric value is used to evaluate the risk associated with different software, which has a direct impact on software trustworthiness. Experiments performed on real software vulnerability datasets and its results are analyzed to check the correctness and effectiveness of the proposed model.

2020-03-23
Karlsson, Linus, Paladi, Nicolae.  2019.  Privacy-Enabled Recommendations for Software Vulnerabilities. 2019 IEEE Intl Conf on Dependable, Autonomic and Secure Computing, Intl Conf on Pervasive Intelligence and Computing, Intl Conf on Cloud and Big Data Computing, Intl Conf on Cyber Science and Technology Congress (DASC/PiCom/CBDCom/CyberSciTech). :564–571.
New software vulnerabilities are published daily. Prioritizing vulnerabilities according to their relevance to the collection of software an organization uses is a costly and slow process. While recommender systems were earlier proposed to address this issue, they ignore the security of the vulnerability prioritization data. As a result, a malicious operator or a third party adversary can collect vulnerability prioritization data to identify the security assets in the enterprise deployments of client organizations. To address this, we propose a solution that leverages isolated execution to protect the privacy of vulnerability profiles without compromising data integrity. To validate an implementation of the proposed solution we integrated it with an existing recommender system for software vulnerabilities. The evaluation of our implementation shows that the proposed solution can effectively complement existing recommender systems for software vulnerabilities.
2020-03-09
Song, Zekun, Wang, Yichen, Zong, Pengyang, Ren, Zhiwei, Qi, Di.  2019.  An Empirical Study of Comparison of Code Metric Aggregation Methods–on Embedded Software. 2019 IEEE 19th International Conference on Software Quality, Reliability and Security Companion (QRS-C). :114–119.

How to evaluate software reliability based on historical data of embedded software projects is one of the problems we have to face in practical engineering. Therefore, we establish a software reliability evaluation model based on code metrics. This evaluation technique requires the aggregation of software code metrics into project metrics. Statistical value methods, metric distribution methods, and econometric methods are commonly-used aggregation methods. What are the differences between these methods in the software reliability evaluation process, and which methods can improve the accuracy of the reliability assessment model we have established are our concerns. In view of these concerns, we conduct an empirical study on the application of software code metric aggregation methods based on actual projects. We find the distribution of code metrics for the projects under study. Using these distribution laws, we optimize the aggregation method of code metrics and improve the accuracy of the software reliability evaluation model.

2020-03-02
Kharchenko, Vyacheslav, Ponochovniy, Yuriy, Abdulmunem, Al-Sudani Mustafa Qahtan, Shulga, Iryna.  2019.  AvTA Based Assessment of Dependability Considering Recovery After Failures and Attacks on Vulnerabilities. 2019 10th IEEE International Conference on Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications (IDAACS). 2:1036–1040.

The paper describes modification of the ATA (Attack Tree Analysis) technique for assessment of instrumentation and control systems (ICS) dependability (reliability, availability and cyber security) called AvTA (Availability Tree Analysis). The techniques FMEA, FMECA and IMECA applied to carry out preliminary semi-formal and criticality oriented analysis before AvTA based assessment are described. AvTA models combine reliability and cyber security subtrees considering probabilities of ICS recovery in case of hardware (physical) and software (design) failures and attacks on components casing failures. Successful recovery events (SREs) avoid corresponding failures in tree using OR gates if probabilities of SRE for assumed time are more than required. Case for dependability AvTA based assessment (model, availability function and technology of decision-making for choice of component and system parameters) for smart building ICS (Building Automation Systems, BAS) is discussed.

2020-02-10
Yang, Jinqiu, Tan, Lin, Peyton, John, A Duer, Kristofer.  2019.  Towards Better Utilizing Static Application Security Testing. 2019 IEEE/ACM 41st International Conference on Software Engineering: Software Engineering in Practice (ICSE-SEIP). :51–60.

Static application security testing (SAST) detects vulnerability warnings through static program analysis. Fixing the vulnerability warnings tremendously improves software quality. However, SAST has not been fully utilized by developers due to various reasons: difficulties in handling a large number of reported warnings, a high rate of false warnings, and lack of guidance in fixing the reported warnings. In this paper, we collaborated with security experts from a commercial SAST product and propose a set of approaches (Priv) to help developers better utilize SAST techniques. First, Priv identifies preferred fix locations for the detected vulnerability warnings, and group them based on the common fix locations. Priv also leverages visualization techniques so that developers can quickly investigate the warnings in groups and prioritize their quality-assurance effort. Second, Priv identifies actionable vulnerability warnings by removing SAST-specific false positives. Finally, Priv provides customized fix suggestions for vulnerability warnings. Our evaluation of Priv on six web applications highlights the accuracy and effectiveness of Priv. For 75.3% of the vulnerability warnings, the preferred fix locations found by Priv are identical to the ones annotated by security experts. The visualization based on shared preferred fix locations is useful for prioritizing quality-assurance efforts. Priv reduces the rate of SAST-specific false positives significantly. Finally, Priv is able to provide fully complete and correct fix suggestions for 75.6% of the evaluated warnings. Priv is well received by security experts and some features are already integrated into industrial practice.

Cetin, Cagri, Goldgof, Dmitry, Ligatti, Jay.  2019.  SQL-Identifier Injection Attacks. 2019 IEEE Conference on Communications and Network Security (CNS). :151–159.
This paper defines a class of SQL-injection attacks that are based on injecting identifiers, such as table and column names, into SQL statements. An automated analysis of GitHub shows that 15.7% of 120,412 posted Java source files contain code vulnerable to SQL-Identifier Injection Attacks (SQL-IDIAs). We have manually verified that some of the 18,939 Java files identified during the automated analysis are indeed vulnerable to SQL-ID IAs, including deployed Electronic Medical Record software for which SQL-IDIAs enable discovery of confidential patient information. Although prepared statements are the standard defense against SQL injection attacks, existing prepared-statement APIs do not protect against SQL-IDIAs. This paper therefore proposes and evaluates an extended prepared-statement API to protect against SQL-IDIAs.
2019-10-14
Angelini, M., Blasilli, G., Borrello, P., Coppa, E., D’Elia, D. C., Ferracci, S., Lenti, S., Santucci, G..  2018.  ROPMate: Visually Assisting the Creation of ROP-based Exploits. 2018 IEEE Symposium on Visualization for Cyber Security (VizSec). :1–8.

Exploits based on ROP (Return-Oriented Programming) are increasingly present in advanced attack scenarios. Testing systems for ROP-based attacks can be valuable for improving the security and reliability of software. In this paper, we propose ROPMATE, the first Visual Analytics system specifically designed to assist human red team ROP exploit builders. In contrast, previous ROP tools typically require users to inspect a puzzle of hundreds or thousands of lines of textual information, making it a daunting task. ROPMATE presents builders with a clear interface of well-defined and semantically meaningful gadgets, i.e., fragments of code already present in the binary application that can be chained to form fully-functional exploits. The system supports incrementally building exploits by suggesting gadget candidates filtered according to constraints on preserved registers and accessed memory. Several visual aids are offered to identify suitable gadgets and assemble them into semantically correct chains. We report on a preliminary user study that shows how ROPMATE can assist users in building ROP chains.

2019-07-01
Carrasco, A., Ropero, J., Clavijo, P. Ruiz de, Benjumea, J., Luque, A..  2018.  A Proposal for a New Way of Classifying Network Security Metrics: Study of the Information Collected through a Honeypot. 2018 IEEE International Conference on Software Quality, Reliability and Security Companion (QRS-C). :633–634.

Nowadays, honeypots are a key tool to attract attackers and study their activity. They help us in the tasks of evaluating attacker's behaviour, discovering new types of attacks, and collecting information and statistics associated with them. However, the gathered data cannot be directly interpreted, but must be analyzed to obtain useful information. In this paper, we present a SSH honeypot-based system designed to simulate a vulnerable server. Thus, we propose an approach for the classification of metrics from the data collected by the honeypot along 19 months.

2018-11-14
Shao, Y., Liu, B., Li, G., Yan, R..  2017.  A Fault Diagnosis Expert System for Flight Control Software Based on SFMEA and SFTA. 2017 IEEE International Conference on Software Quality, Reliability and Security Companion (QRS-C). :626–627.
Many accidents occurred frequently in aerospace applications, traditional software reliability analysis methods are not enough for modern flight control software. Developing a comprehensive, effective and intelligent method for software fault diagnosis is urgent for airborne software engineering. Under this background, we constructed a fault diagnosis expert system for flight control software which combines software failure mode and effect analysis with software fault tree analysis. To simplify the analysis, the software fault knowledge of four modules is acquired by reliability analysis methods. Then by taking full advantage of the CLIPS shell, knowledge representation and inference engine can be realized smoothly. Finally, we integrated CLIPS into VC++ to achieve visualization, fault diagnosis and inference for flight control software can be performed in the human-computer interaction interface. The results illustrate that the system is able to diagnose software fault, analysis the reasons and present some reasonable solutions like a human expert.
2018-05-02
Shanthi, D., Mohanty, R. K., Narsimha, G., Aruna, V..  2017.  Application of partical swarm intelligence technique to predict software reliability. 2017 International Conference on Intelligent Computing and Control Systems (ICICCS). :629–635.

Predict software program reliability turns into a completely huge trouble in these days. Ordinary many new software programs are introducing inside the marketplace and some of them dealing with failures as their usage/managing is very hard. and plenty of shrewd strategies are already used to are expecting software program reliability. In this paper we're giving a sensible knowledge and the difference among those techniques with my new method. As a result, the prediction fashions constructed on one dataset display a extensive decrease in their accuracy when they are used with new statistics. The aim of this assessment, SE issues which can be of sensible importance are software development/cost estimation, software program reliability prediction, and so forth, and also computing its broaden computational equipment with enhanced power, scalability, flexibility and that can engage more successfully with human beings.

2018-04-04
Majumder, R., Som, S., Gupta, R..  2017.  Vulnerability prediction through self-learning model. 2017 International Conference on Infocom Technologies and Unmanned Systems (Trends and Future Directions) (ICTUS). :400–402.

Vulnerability being the buzz word in the modern time is the most important jargon related to software and operating system. Since every now and then, software is developed some loopholes and incompleteness lie in the development phase, so there always remains a vulnerability of abruptness in it which can come into picture anytime. Detecting vulnerability is one thing and predicting its occurrence in the due course of time is another thing. If we get to know the vulnerability of any software in the due course of time then it acts as an active alarm for the developers to again develop sound and improvised software the second time. The proposal talks about the implementation of the idea using the artificial neural network, where different data sets are being given as input for being used for further analysis for successful results. As of now, there are models for studying the vulnerabilities in the software and networks, this paper proposal in addition to the current work, will throw light on the predictability of vulnerabilities over the due course of time.

2018-03-26
Movahedi, Y., Cukier, M., Andongabo, A., Gashi, I..  2017.  Cluster-Based Vulnerability Assessment Applied to Operating Systems. 2017 13th European Dependable Computing Conference (EDCC). :18–25.

Organizations face the issue of how to best allocate their security resources. Thus, they need an accurate method for assessing how many new vulnerabilities will be reported for the operating systems (OSs) they use in a given time period. Our approach consists of clustering vulnerabilities by leveraging the text information within vulnerability records, and then simulating the mean value function of vulnerabilities by relaxing the monotonic intensity function assumption, which is prevalent among the studies that use software reliability models (SRMs) and nonhomogeneous Poisson process (NHPP) in modeling. We applied our approach to the vulnerabilities of four OSs: Windows, Mac, IOS, and Linux. For the OSs analyzed in terms of curve fitting and prediction capability, our results, compared to a power-law model without clustering issued from a family of SRMs, are more accurate in all cases we analyzed.

2018-03-19
Popov, P..  2017.  Models of Reliability of Fault-Tolerant Software Under Cyber-Attacks. 2017 IEEE 28th International Symposium on Software Reliability Engineering (ISSRE). :228–239.

This paper offers a new approach to modelling the effect of cyber-attacks on reliability of software used in industrial control applications. The model is based on the view that successful cyber-attacks introduce failure regions, which are not present in non-compromised software. The model is then extended to cover a fault tolerant architecture, such as the 1-out-of-2 software, popular for building industrial protection systems. The model is used to study the effectiveness of software maintenance policies such as patching and "cleansing" ("proactive recovery") under different adversary models ranging from independent attacks to sophisticated synchronized attacks on the channels. We demonstrate that the effect of attacks on reliability of diverse software significantly depends on the adversary model. Under synchronized attacks system reliability may be more than an order of magnitude worse than under independent attacks on the channels. These findings, although not surprising, highlight the importance of using an adequate adversary model in the assessment of how effective various cyber-security controls are.

2018-02-21
Ristov, P., Mišković, T., Mrvica, A., Markić, Z..  2017.  Reliability, availability and security of computer systems supported by RFID technology. 2017 40th International Convention on Information and Communication Technology, Electronics and Microelectronics (MIPRO). :1459–1464.

The implementation of RFID technology in computer systems gives access to quality information on the location or object tracking in real time, thereby improving workflow and lead to safer, faster and better business decisions. This paper discusses the quantitative indicators of the quality of the computer system supported by RFID technology applied in monitoring facilities (pallets, packages and people) marked with RFID tag. Results of analysis of quantitative indicators of quality compute system supported by RFID technology are presented in tables.

2018-02-02
Chen, L., May, J..  2017.  Theoretical Feasibility of Statistical Assurance of Programmable Systems Based on Simulation Tests. 2017 IEEE International Conference on Software Quality, Reliability and Security Companion (QRS-C). :630–631.

This presents a new model to support empirical failure probability estimation for a software-intensive system. The new element of the approach is that it combines the results of testing using a simulated hardware platform with results from testing on the real platform. This approach addresses a serious practical limitation of a technique known as statistical testing. This limitation will be called the test time expansion problem (or simply the 'time problem'), which is that the amount of testing required to demonstrate useful levels of reliability over a time period T is many orders of magnitude greater than T. The time problem arises whether the aim is to demonstrate ultra-high reliability levels for protection system, or to demonstrate any (desirable) reliability levels for continuous operation ('high demand') systems. Specifically, the theoretical feasibility of a platform simulation approach is considered since, if this is not proven, questions of practical implementation are moot. Subject to the assumptions made in the paper, theoretical feasibility is demonstrated.

Santos, J. C. S., Tarrit, K., Mirakhorli, M..  2017.  A Catalog of Security Architecture Weaknesses. 2017 IEEE International Conference on Software Architecture Workshops (ICSAW). :220–223.

Secure by design is an approach to developing secure software systems from the ground up. In such approach, the alternate security tactics are first thought, among them, the best are selected and enforced by the architecture design, and then used as guiding principles for developers. Thus, design flaws in the architecture of a software system mean that successful attacks could result in enormous consequences. Therefore, secure by design shifts the main focus of software assurance from finding security bugs to identifying architectural flaws in the design. Current research in software security has been neglecting vulnerabilities which are caused by flaws in a software architecture design and/or deteriorations of the implementation of the architectural decisions. In this paper, we present the concept of Common Architectural Weakness Enumeration (CAWE), a catalog which enumerates common types of vulnerabilities rooted in the architecture of a software and provides mitigation techniques to address them. The CAWE catalog organizes the architectural flaws according to known security tactics. We developed an interactive web-based solution which helps designers and developers explore this catalog based on architectural choices made in their project. CAWE catalog contains 224 weaknesses related to security architecture. Through this catalog, we aim to promote the awareness of security architectural flaws and stimulate the security design thinking of developers, software engineers, and architects.

Xu, B., Lu, M., Zhang, D..  2017.  A Software Security Case Developing Method Based on Hierarchical Argument Strategy. 2017 IEEE International Conference on Software Quality, Reliability and Security Companion (QRS-C). :632–633.

Security cases-which document the rationale for believing that a system is adequately secure-have not been sufficiently used for a lack of practical construction method. This paper presents a hierarchical software security case development method to address this issue. We present a security concept relationship model first, then come up with a hierarchical asset-threat-control measure argument strategy, together with the consideration of an asset classification and threat classification for software security case. Lastly, we propose 11 software security case patterns and illustrate one of them.

Rotella, P., Chulani, S..  2017.  Predicting Release Reliability. 2017 IEEE International Conference on Software Quality, Reliability and Security Companion (QRS-C). :39–46.

Customers need to know how reliable a new release is, and whether or not the new release has substantially different, either better or worse, reliability than the one currently in production. Customers are demanding quantitative evidence, based on pre-release metrics, to help them decide whether or not to upgrade (and thereby offer new features and capabilities to their customers). Finding ways to estimate future reliability performance is not easy - we have evaluated many prerelease development and test metrics in search of reliability predictors that are sufficiently accurate and also apply to a broad range of software products. This paper describes a successful model that has resulted from these efforts, and also presents both a functional extension and a further conceptual simplification of the extended model that enables us to better communicate key release information to internal stakeholders and customers, without sacrificing predictive accuracy or generalizability. Work remains to be done, but the results of the original model, the extended model, and the simplified version are encouraging and are currently being applied across a range of products and releases. To evaluate whether or not these early predictions are accurate, and also to compare releases that are available to customers, we use a field software reliability assessment mechanism that incorporates two types of customer experience metrics: field bug encounters normalized by usage, and field bug counts, also normalized by usage. Our 'release-overrelease' strategy combines the 'maturity assessment' component (i.e., estimating reliability prior to release to the field) and the 'reliability assessment' component (i.e., gauging actual reliability after release to the field). This overall approach enables us to both predict reliability and compare reliability results for recent releases for a product.

2017-12-28
Vizarreta, P., Heegaard, P., Helvik, B., Kellerer, W., Machuca, C. M..  2017.  Characterization of failure dynamics in SDN controllers. 2017 9th International Workshop on Resilient Networks Design and Modeling (RNDM). :1–7.

With Software Defined Networking (SDN) the control plane logic of forwarding devices, switches and routers, is extracted and moved to an entity called SDN controller, which acts as a broker between the network applications and physical network infrastructure. Failures of the SDN controller inhibit the network ability to respond to new application requests and react to events coming from the physical network. Despite of the huge impact that a controller has on the network performance as a whole, a comprehensive study on its failure dynamics is still missing in the state of the art literature. The goal of this paper is to analyse, model and evaluate the impact that different controller failure modes have on its availability. A model in the formalism of Stochastic Activity Networks (SAN) is proposed and applied to a case study of a hypothetical controller based on commercial controller implementations. In case study we show how the proposed model can be used to estimate the controller steady state availability, quantify the impact of different failure modes on controller outages, as well as the effects of software ageing, and impact of software reliability growth on the transient behaviour.