Computer Engineering / Bilgisayar Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/10
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Article Bağlamsal Doğrulama için Bir Yazılım Tasarım Şablonu(Dokuz Eylül Üniversitesi, 2017) Tuğlular, TuğkanYazılım tasarım şablonları, tekrar eden yazılım tasarım problemleri için hazır çözümler sunar. Model-Görünüm-Denetçi (İng. MVC) gibi bileşik tasarım şablonları ise, var olan tasarım şablonlarının biraraya getirilmesi ile daha büyük ölçekli problemleri çözmek için geliştirilmektedir. Bu çalışmada bağlamsal doğrulama problemi için bir bileşik tasarım şablonu geliştirilmiştir. Bağlamsal doğrulama, bir işlem gerçekleş- tirilmeden önce o işlem için gerekli tüm nesnelerin gerekli koşulları sağladığının doğrulanması anlamına gelmektedir. Bileşik tasarım şablonu geliştirme yöntemi ile ortaya konan bağlamsal doğrulama tasarım şablonu; tek sorumluluk, açık-kapalı ve bağımlılığı tersine çevirme nesne temelli tasarım ilkelerine göre geliştirilmiştir. Geliştirilen bağlamsal doğrulama tasarım şablonu bünyesinde Ziyaretçi, Strateji, Dekoratör ve Bildirim tasarım şablonlarını barındırmaktadır. Ortaya konan bağlamsal doğrulama tasarım şablonu, kullanım şekli itibariyle iki örnek uygulama üzerinde tartışılmıştır.Editorial Message From Tain Symposium Organizing Committee(Institute of Electrical and Electronics Engineers Inc., 2015) Tuğlular, Tuğkan; Cai, Y.; Dustdar, S.; Yamazaki, K.It is a pleasure to welcome you to COMPSAC 2015 Symposium on Technologies and Applications of the Internet (TAIN). This year, first time in its history, COMPSAC is organized as a series of symposiums under the main theme of “Mobile and Cloud Systems – Challenges and Applications”. TAIN Symposium providing a forum to share latest innovations on Internet technologies and applications perfectly matches with the main theme. Topics of interest for TAIN include all types of networks with their architectures and applications as well as their management, performance, and security. Moreover, TAIN Symposium addresses Internet of things (IoT), machine-to-machine (M2M) and peer-to-peer (P2P) communications, content distribution networks (CDN) and also emerging network technologies such as software defined networks (SDN). A vast array of challenges for Internet technologies and applications and proposals for solutions will be discussed in TAIN Symposium.Conference Object Citation - WoS: 1Automatic Enforcement of Location Aware User Based Network Access Control Policies(World Scientific and Engineering Academy and Society, 2008) Tuğlular, TuğkanMultiple interconnected network segments distributed across various locations, such as corporate networks, where users or employees constantly travel among segments and require to access servers, need to have network access control mechanisms that are able to adapt to these location changes. The idea of a firewall changing or adapting its rules depending on the location of users is presented by an architecture in this paper. This architecture proposes deployment of a policy server at the management level and policy agents at the firewall level, so that policy-driven network security management is enabled by specifying location aware user based network access control policies at the network security management and enforcing them at the managed firewalls. The architecture presented in this paper utilizes user VPN connection event triggers for dynamic policy configuration and automated policy deployment to firewalls. Location aware user based network access control policies, which are management level policies, are implemented using XACML. A network level policy is usually a configuration, or policy, file local to the firewall. The policy agent incorporated into the firewall performs the mapping from management level policy to firewall policy.Conference Object Citation - Scopus: 4Test Case Generation for Firewall Implementation Testing Using Software Testing Techniques(Tafford Publishing, 2008) Tuğlular, TuğkanThe firewall implementation testing approach checks actions performed by the firewall with respect to corresponding firewall rules. This type of firewall testing can be implemented by developing test cases from firewall rule sequence, generating test packets using those test cases and injecting those test packets into the firewall. Although this method has been already defined in the academic world, an approach to generate test cases does not exist in the literature. In this work, a test case generation approach is developed using software testing techniques. © 2008 Atilla Elçi.Conference Object Monitoring of Policy Operations in a Distributed Firewall Environment(2008) Çakı, Oğuzhan; Tuğlular, Tuğkan; Çetin, FüsunDistributed firewalls concept has been introduced to overcome some drawbacks of traditional firewalls. Distributed firewall approach is based on the idea of enforcing policy rules at the intermediate and end points rather than a single entry point to the network. Management of policy rules in a distributed firewall environment requires surveillance of policy operations performed on each firewall. With this paper, we propose a monitoring architecture and its application prototype for distributed firewalls to keep track of actions, such as create, read, update, and delete, carried out on policy rule sets. We performed some emulation and laboratory experiments to obtain operational values of the proposed architecture. ©2008 by Bo?aziçi University.Article Citation - WoS: 9Citation - Scopus: 14Rule-Based Automatic Question Generation Using Semantic Role Labeling(Institute of Electronics, Information and Communication Engineers, 2019) Keklik, Onur; Tuğlular, Tuğkan; Tekir, SelmaThis paper proposes a new rule-based approach to automatic question generation. The proposed approach focuses on analysis of both syntactic and semantic structure of a sentence. Although the primary objective of the designed system is question generation from sentences, automatic evaluation results shows that, it also achieves great performance on reading comprehension datasets, which focus on question generation from paragraphs. Especially, with respect to METEOR metric, the designed system significantly outperforms all other systems in automatic evaluation. As for human evaluation, the designed system exhibits similar performance by generating the most natural (human-like) questions.Conference Object Citation - WoS: 3Citation - Scopus: 6Spl-At Gherkin: a Gherkin Extension for Feature Oriented Testing of Software Product Lines(IEEE, 2019) Tuğlular, Tuğkan; Şensülün, SecanAs cloud platforms turn into software product lines (SPLs), testing products composed of customer selected features becomes more and more important. In this paper, we propose a feature-oriented testing approach for platform-based SPLs through a novel extension to Gherkin called SPL-AT Gherkin and a novel automatic test method generation technique, which utilizes TestNG framework. We demonstrate the applicability of the proposed approach by a case study.Conference Object Citation - WoS: 5Citation - Scopus: 5Featured Event Sequence Graphs for Model-Based Incremental Testing of Software Product Lines(IEEE, 2019) Tuğlular, Tuğkan; Beyazıt, Mutlu; Öztürk, DilekThe goal of software product lines (SPLs) is rapid development of high-quality software products in a specific domain with cost minimization. To assure quality of software products from SPLs, products need to be tested systematically. However, testing every product variant in isolation is generally not feasible for large number of product variants. An approach to deal with this issue is to use incremental testing, where test artifacts that are developed for one product are reused for another product which can be obtained by incrementally adding features to the prior product. We propose a novel model-based test generation approach for products developed using SPL that follows incremental testing paradigm. First, we introduce Featured Event Sequence Graphs (FESGs), an extension of ESGs, that provide necessary definitions and operations to support commonalities and variabilities in SPLs with respect to test models. Then we propose a test generation technique for the product variants of an SPL, which starts from any product. The proposed technique with FESGs avoids redundant test generation for each product from SPL. We compare our technique with in-isolation testing approach by a case study.Article Model-Based Selective Layer-Centric Testing(Information Processing Society of Japan, 2018) Belli, Fevzi; Güler Dinçer, Nevin; Linschulte, Michael; Tuğlular, TuğkanModel-based testing of large systems usually requires decomposition of the model into hierarchical submodels for generating test sequences, which fulfills the goals of module testing, but not those of system testing. System testing requires test sequences be generated from a fully resolved model, which necessitates refining the toplevel model, that is, by replacing its elements with submodels they represent. If the depth of model hierarchy is high, the number of test sequences along with their length increases resulting in high test costs. For solving this conflict, a novel approach is introduced that generates test sequences based on the top-level model and replaces elements of these sequences by corresponding, optimized test sequences generated by the submodels. To compensate the shortcoming at test accuracy, the present approach selects components that have lowering impact on the overall system reliability. The objective is to increase the reliabilities of these critical components by intensive testing and appropriate correction which, as a consequence, also increases the overall reliability at less test effort without losing accuracy. An empirical study based on a large web-based commercial system is performed to validate the approach and analyze its characteristics, and to discuss its strengths and weaknesses. © 2018 Information Processing Society of Japan.Article Citation - WoS: 6Citation - Scopus: 6Estimating Software Robustness in Relation To Input Validation Vulnerabilities Using Bayesian Networks(Springer Verlag, 2018) Ufuktepe, Ekincan; Tuğlular, TuğkanEstimating the robustness of software in the presence of invalid inputs has long been a challenging task owing to the fact that developers usually fail to take the necessary action to validate inputs during the design and implementation of software. We propose a method for estimating the robustness of software in relation to input validation vulnerabilities using Bayesian networks. The proposed method runs on all program functions and/or methods. It calculates a robustness value using information on the existence of input validation code in the functions and utilizing common weakness scores of known input validation vulnerabilities. In the case study, ten well-known software libraries implemented in the JavaScript language, which are chosen because of their increasing popularity among software developers, are evaluated. Using our method, software development teams can track changes made to software to deal with invalid inputs.