Zeljko Stojanov

Using Virtualization Software in Operating Systems Course

Virtualization technology has been developing for years. Nowadays, it is revived with a large scale of different software applications. One of the methods of virtualization technology appliance is in the creation or virtual network laboratories. Virtual network laboratories are used for networking research and experiments, and as well as for education of engineers at universities. The question is, can virtualization be used in other courses in higher education. This paper presents an approach of using virtualization software as a simulation tool for virtual laboratory in operating system course. This work is the first phase of ongoing research in adopting virtualization technology usage in high education.

Identifying properties of software change request process: Qualitative investigation in very small software companies

Software systems change during all phases of their life cycles. After software delivery, users should have effective ways for specifying new requests and reporting problems. Handling of this new requests or problem reports must be supported with sound processes and appropriate tools. In this paper is presented a segment of qualitative research conducted with software experts from very small software companies related to change request process in maintenance phase of software life cycle. Software experts were interviewed in their companies or participated in focus groups. This research used constructivist grounded theory that is suitable methodology for creating explanations of common practice. Analysis of qualitative empirical data revealed properties regarding process implementation, the level of automation, feedback, iterativeness and process duration.

Discovering automation level of software change request process from qualitative empirical data

This paper presents an approach in discovering automation level of software change request process from qualitative empirical data. In the study is investigated common practice in local very small software companies. Constructivist grounded theory was used as a research method suitable for discovering common practice and for creating explanations that are grounded in empirical data. In the research participated software experts from local very small software companies. Software experts were interviewed individually in their companies or participated in organized focus groups. The process of qualitative research that is used in the study is outlined, followed by the research findings. Analysis of empirical data reveals that very small software companies do not have automated software change request process, or have automated only parts of the process.

Modeling a submission phase of change request process in context of a running application

Nowadays many companies must adapt their business processes to persistent changes forced by technology, organizational or political factors. Business processes are usually supported by specialized software products. These software products also must adapt to changed business environments. Software users must have effective way to specify new requests for software they use. In this paper is presented model of modified submission phase for software change request process. This model is implemented and verified in ScenarioBuilder, a software used for management of networking scenarios in virtual network laboratory VNLab. VNLab is used for teaching networking concepts at university course.

Usability of virtual network laboratory in engineering education and computer network course

The importance of educational process in the field of Computer Science and Information Technology industry, as well as the need for educating highly skilled computer network professionals implies the importance of its course syllabus and laboratory tools. This paper presents evaluation and analysis of virtual network laboratory based on virtualization technology. The virtual network laboratory architecture is shown together with the supporting laboratory exercises. Evaluation criteria for these laboratory exercises include: description of learning goals, adopted skills, compatibility with course syllabus and side knowledge, and additional skills. Lessons learned after the virtual network laboratory course, are gathered as well. Detailed analysis of the skills and knowledge that students adopted in this environment is summarized. Also, overall usability estimation in education of various engineering profiles and related computer networking and communication courses is shown.

An approach in modifying submission phase of change request process

Software systems change during the whole life cycle. Support for changes that origin in development process is provided by wide range of tools and techniques. Changes that appear during the software maintenance phase usually are driven by customers. These changes, specified as change requests, are usually submitted via developerspsila web site. After initial specification and submission these change requests pass the phases of standard change process that is integrated into software development process. Change requests specification should provide enough information for all phases of change request process. Support for change request specification is typically realized at developer side. In this paper is presented an approach in specifying change request in context of running application at customer side. This approach introduces modification of initial phase of standard change request process with aim to provide detailed specification of change request closely related to architecture of software.

Teaching Application Development for RFID/ZigBee Networks using Open Source Hardware

Concepts related to Wireless Sensor Networks (WSN), Machine-to-Machine (M2M) and the Internet of Things (IoT) have recently gained significant attention in university education. According to this, the need for low-cost, modular, easy-to-use and scalable platform used for building various network systems in order to provide an environment for developing and testing software applications for WSN, IoT and related technologies is very high. This paper presents an approach in creating platform based on open source hardware designed to provide an infrastructure for teaching development of software applications for WSN, in this case applications for RFID/ZigBee networks, to be used in Computing education and profession.

Testing Zigbee RF module applicability for usage in temperature monitoring systems

The applications of wireless technologies in industrial automation, monitoring and control systems has already proved itself. The technologies like IEEE 802.15.4, ZigBee, Bluetooth Low Energy, WirelessHART, Wi-Fi and others are widely used in sensor networks environments. This paper presents the approach of evaluating the applicability of open-source ZigBee RF module MeshBee® in wireless sensor environments and for potential use in monitoring and control systems. This paper presents the platform and experiment for ZigBee module evaluation. The platform presented in this paper is based on widely used microcontroller unit Arduino UNO Rev3 in combination with MeshBee® wireless module.

Software application for analyzing ZigBee network performance in university courses

Wireless Sensor Networks (WSN) and related technologies have the important impact nowadays. These technologies have variety of applications, and they are key enabling technologies of IoT (Internet of Things). ZigBee standard is the most common WSN technology. Its importance and expansion, as a widely used technology in many different areas, influence the importance of including ZigBee technology in courses at university. This paper presents the software application and related hardware platform designed to be used by the students to measure and analyze the performances of ZigBee network in design and pre-implementation process. The presented application can be used during the classes of Communication Systems and Computer Network Courses for ZigBee traffic and packet analyses. In addition, this application can be used for researching in the field of wireless sensor networks, ZigBee and other similar popular technologies such as Bluetooth Low Energy, IEEE 802.15.4, etc. The supporting platform for this application and experiment for its evaluation are also presented in this paper.

Context dependent maintenance effort estimation: Case study in a small software company

This paper presents an approach to software maintenance effort estimation based on the analysis of software maintenance requests available in issue tracking system in a very small local software company. Over 1900 requests, collected during 19 months in 2010 and 2011, were selected for analysis. The approach takes into account: the frequency of submitted user requests for particular periods of time important for organizing work in the company, the existence of maintenance service agreement for clients, the number of programmers assigned to the task associated to each request, and the number of working hours required for requests solving. The approach calculates correlation and establishes linear regression between frequencies of submitted user requests and the average time required for completing requests. This approach estimates an average number of working hours for processing user requests in periods of time that are important for internal company organization. In the paper are also discussed implications for practice and research, and provided recommendations for adapting this approach to other small software companies.