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The heterogeneous structure and dynamic nature of web applications have made the testing procedure a challenge. Producing high-quality web applications can be performed by conducting appropriate testing techniques. As a result, several white-box and session-based testing techniques have been proposed in the literature. In this work, the performance and effectiveness of these testing techniques are evaluated in terms of fault detection on a simulated PHP online bookstore. The testing techniques are examined with the use of PHPUnit, xDebug and Selenium automated testing tools. We believe that combining the testing techniques with appropriate automated testing tools (PHPUnit and Selenium) can be effective in terms of fault detection and time spent to construct and run test cases on PHP web applications. The results show that some testing techniques are preferred. We also identify categories of faults that are amenable to detection by each of the techniques, as well as categories of faults that are difficult to detect by any of the techniques. Moreover, using the automated tools has helped in automating the conduct of the tests and in reducing the time required to perform them. / Thesis / Master of Applied Science (MASc)

This thesis is missing pages 68, 118, 129 and 189 and these pages are not in any other copies of the thesis. -Digitization Centre / This thesis is a design of a three-dimensional plotting routine for the computer facilities at McMaster University with a subroutine to adopt the package for use on other computer systems and is divided into four sections. Section A is a review of the necessity of computerized plotting in science and engineering design with particular emphasis on software sophistication, which is the subject of this work. Section B describes the principles employed and the basic logic of the software package. The method by which a three-dimensional solid is mapped is also explained. Section C is a complete user's guide to the package. Section D deals with some applications for the package such as the solution of design optimization problems, visual analysis of data sets, an aid to teaching and combined interpolation and display of experimental results. / Thesis / Master of Engineering (ME)

The Session Initiation Protocol (SIP) was first published in 1999, by the Internet Engineering Task Force (IETF), to be the standard for multimedia transfers. SIP is a peer-to-peer signaling protocol that is capable of initiating, modifying, and terminating media sessions. SIP utilizes existing Internet Protocols (IP) such as Domain Name Service (DNS) and the Session Description Protocol (SDP), allowing it to seamlessly integrate into existing IP networks. As SIP has matured and gained acceptance, its deficiencies when functioning as a multipoint communications protocol have become apparent. SIP currently supports two modes of operation referred to as conferencing and multicasting. Conferencing is the unicast transmission of session information between conference members. Multicasting uses IP multicast to distribute session information. This thesis proposes an extension for the Session Initiation Protocol that improves functionality for multipoint communications. When using conferencing, a SIP user-agent has limited information about the conference it is taking part in. This extension increases the awareness of a SIP node by providing it with complete conference membership information, the ability to detect neighboring node failures, and the ability to automatically repair conference partitions. Signaling for conferencing was defined and integrated into a standard SIP implementation where it was used to demonstrate the above capabilities. Using a prototype implementation, the additional functionality was shown to come at the cost of a modest increase in transaction message size and processing complexity. IP multicast has limited deployment in today's networks reducing the usability of this useful feature. Since IP multicast support is not guaranteed, the use of application layer multicast protocols is proposed to replace the use of IP multicast. An efficient means of negotiating an application layer protocol is proposed as well as the ability to provide the protocol with session information to begin operation. A ring protocol was defined and implemented using the proposed extension. Performance testing revealed that the application layer protocol had slightly higher processing complexity than conferencing, but on average had a smaller transaction message size. / Master of Science

Internet Protocol version 6 (IPv6) is being adopted in networks around the world as the Internet Protocol version 4 (IPv4) addressing space reaches its maximum capacity. Although there are IPv6 applications being developed, there are not many production IPv6 networks in place in which these applications can be deployed. Simulation presents a cost effective alternative to setting up a live test bed of devices to validate specific IPv6 environments before actual physical deployment. OPNET Modeler provides the capability to simulate the IPv6 protocol and System-in-the-Loop, an add-on module, allows for real communication traffic from physical devices to be converted and sent over the simulated network. This research has developed a campus framework, modeled after the Virginia Tech Blacksburg campus, to verify and validate standard and custom IPv6 applications. Specifically, the framework was used to test MT6D, a custom IPv6 security application developed in the Virginia Tech IT Security Lab (ITSL) as well as test Voice over IP (VoIP) as a somewhat bandwidth demanding benchmarking standard application. The work presented shows that simulation helped to identify potential issues within the applications and verified the results after fixes were applied. It also reveals challenges and shortcomings of OPNET Modeler's IPv6 implementation and presents potential solutions to these problems. / Master of Science

Software-intensive systems operating in a shared environment must utilize a "request, acquire and release" protocol. In the popular client-server architecture resource-poor clients rely on servers for the needed capabilities. With mobile clients using wireless connectivity, the disparity in resource needs can force the consideration of adaptation by clients, leading to a strategy of self-reliance. Achieving self-reliance through adaptation becomes even more attractive in environments, which are dynamic and continually changing. A more comprehensive strategy is for the mobile client to recognize the changing resource levels and plan for any such degradation; that is, the applications in the mobile client need to adapt to the changing environment and availability of resources. Portable adaptation middleware that is sensitive to architecture and context changes in network operations is designed and implemented. The Adaptation Middleware not only provides the flexibility for the client applications to adapt to changing resources around them, but also to changing resource levels within the client applications. Further, the Adaptation Middleware imposes few changes on the structure of the client application. The Adaptation Middleware creates the adaptations; the client remains unaware and unconcerned with these adaptations. The Adaptation Middleware in this study also enables a more informative cost estimation with regard to applications such as mobile agents. A sample application developed using the Adaptation Middleware shows performance improvements in the range of 31% to 54%. A limited set of experiments show an average response time of 68 milliseconds, which seems acceptable for most applications. Further, the Adaptation Middleware permits increased stability for applications demonstrating demand levels subject to high uncertainty. / Master of Science

Intrusion detection systems are an integral part of web application security. As Internet use continues to increase, the demand for fast, accurate intrusion detection systems has grown. Various IDSs like Snort, Zeek, Solarwinds SEM, and Sleuth9, detect malicious intent based on existing patterns of attack. While these systems are widely deployed, there are limitations with their approach, and anomaly-based IDSs that classify baseline behavior and trigger on deviations were developed to address their shortcomings. Existing anomaly-based IDSs have limitations that are typical of any machine learning system, including high false-positive rates, a lack of clear infrastructure for deployment, the requirement for data to be centralized, and an inability to add modules tailored to specific organizational threats. To address these shortcomings, our work proposes a system that is distributed in nature, can actively learn and uses experts to improve accuracy. Our results indicate that the integrated system can operate independently as a holistic system while maintaining an accuracy of 99.03%, a false positive rate of 0.5%, and speed of processing 160,000 packets per second for an average system. / Master of Science / Intrusion detection systems are an integral part of web application security. The task of an intrusion detection system is to identify attacks on web applications. As Internet use continues to increase, the demand for fast, accurate intrusion detection systems has grown. Various IDSs like Snort, Zeek, Solarwinds SEM, and Sleuth9, detect malicious intent based on existing attack patterns. While these systems are widely deployed, there are limitations with their approach, and anomaly-based IDSs that learn a system's baseline behavior and trigger on deviations were developed to address their shortcomings. Existing anomaly-based IDSs have limitations that are typical of any machine learning system, including high false-positive rates, a lack of clear infrastructure for deployment, the requirement for data to be centralized, and an inability to add modules tailored to specific organizational threats. To address these shortcomings, our work proposes a system that is distributed in nature, can actively learn and uses experts to improve accuracy. Our results indicate that the integrated system can operate independently as a holistic system while maintaining an accuracy of 99.03%, a false positive rate of 0.5%, and speed of processing 160,000 packets per second for an average system.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Software applications’ performance is hindered by a variety of factors, but most notably by the well-known CPU-memory speed gap (often known as the memory wall). This results in the CPU sitting idle waiting for data to be brought from memory to processor caches. The addressing used by caches cause non-uniform accesses to various cache sets. The non-uniformity is due to several reasons, including how different objects are accessed by the code and how the data objects are located in memory. Memory allocators determine where dynamically created objects are placed, thus defining addresses and their mapping to cache locations. It is important to evaluate how different allocators behave with respect to the localities of the created objects. Most allocators use a single attribute, the size, of an object in making allocation decisions. Additional attributes such as the placement with respect to other objects, or specific cache area may lead to better use of cache memories. In this dissertation, we proposed and implemented a framework that allows for the development and evaluation of new memory allocation techniques. At the root of the framework is a memory tracing tool called Gleipnir, which provides very detailed information about every memory access, and relates it back to source level objects. Using the traces from Gleipnir, we extended a commonly used cache simulator for generating detailed cache statistics: per function, per data object, per cache line, and identify specific data objects that are conflicting with each other. The utility of the framework is demonstrated with a new memory allocator known as equivalence class allocator. The new allocator allows users to specify cache sets, in addition to object size, where the objects should be placed. We compare this new allocator with two well-known allocators, viz., Doug Lea and Pool allocators.

The massive rise in Computer Science enrollments in both traditional classroom courses and in Massively Open Online Courses (MOOCs) shows the enormous opportunities in engaging students to learn programming. While the number of students in CS courses continues to increase, there has been no concomitant increase in the number of instructors for such courses. This leads to a completely lopsided learning environment where the already-stretched instructor is pressed to spend more time on ancillary tasks like grading and course bookkeeping. CodeWorkout is an online drill-and-practice system with course management features that aims to address these issues. CodeWorkout hosts an online repository of programming questions that instructors can incorporate into their courses. It also provides instructors with a facility to create their own programming questions so that exercises can be tailored according to the needs of the class. CodeWorkout has an open gradual engagement model that allows students who are not enrolled in a course to use it. CodeWorkout also creates an open environment for instructors to collaborate by sharing exercises that they create. CodeWorkout has been used in four courses at Virginia Tech. It has been shown to significantly improve the student's skills in introductory programming through providing a number of online practice questions. / Master of Science