Mitko Shopov

Technical University of Sofia - Branch Plovdiv · Department of Computer Systems and Technologies

Containerization is still a relatively new and fast evolving technology. It has been widely adopted in cloud environments, because of its lower overhead compared to virtualization. Besides the benefits of using containers for running applications in virtual environments a lot of challenges in terms of security arise. The paper presents an overview...

The paper presents an implementation of a smart home architecture with two gateways based on collaboration of blockchain technology and Internet of Things (IoT) Message oriented middleware (MOM) architecture for management of internal home appliances. A basic overview of IoT MOM, MQTT (Message Queue Telemetry Transfer) protocol and blockchain archi...

The paper presents an example Sensor-cloud architecture that integrates security as its native ingredient. It is based on the multi-layer client-server model with separation of physical and virtual instances of sensors, gateways, application servers and data storage. It proposes the application of virtualised sensor nodes as a prerequisite for incr...

Abstract - This paper presents a practical implementation of a private cloud, based on VMware technology, optimized to support CoS and QoS (even when overlay technology like VXLAN is used) in a field of smart metering in electrical power systems and IoT. The use of cloud computing technologies increase reliability and availability of the system. Al...

The aim of the thesis is the study and optimization of network architectures implemented through wireless biomedical sensors and a personal monitor, given the opportunities to integrate them into web-based systems for personalized healthcare (PHS). A three-layered reference model for the implementation of web-based PHS is proposed. The model aims...

The paper suggests a model for implementation of a body sensor network's gateway functions. The gateway is based on a mobile smartphone with a Linux kernel. Analysis on traffic management schemes based on different queue disciplines is presented in the paper. Since the gateway is modeled as a standard mobile device, the typical traffic flows for su...

The paper aims to provide a reference manual for using Linux/GNU tools in developing embedded Internet-ready applications for ARM9 based systems. It provides steps-by-step guide for configuring the bootloader, Linux kernel, toolchain and developing environment. As an example ARM920T based development board (EP9302) is used, running 2.6.32 kernel an...

The paper presents a testbed configuration for evaluation of performance parameters of a zigbee-based body sensor network operating in ISM 2,4GHz radio frequency band. Both stand-alone and co-existence scenarios are included in experiments. Since security is an important characteristic of body sensor networks, both encrypted and non-encrypted traff...

The paper presents an analysis of Bluetooth wireless technology and the new features around Bluetooth Health Device Profile (HDP) and low power operation mode. The advantage of introducing HDP and different optimization techniques in Body Sensor Networks are also discussed in the paper. The focal point of the analysis is the achievement of high int...

The paper presents an experimental testbed environment for analysis of protocols and processes in body sensors networks. It consists of an embedded gateway and a set of wireless sensors. The embedded gateway is equipped with various communication interfaces including Ethernet, WLAN, Bluetooth, and ZigBee. It is responsible for coordination of the s...

The paper presents an application level protocol for data interactions in local networks of embedded devices and its adaptation for Personal Health Systems and Body Sensor networks. The protocol uses profiles to improve scalability and applicability and to ease the customization for different application areas. Profiles are described in XML to be e...

Paper presents a Web-based Personal Health System (PHS) for remote monitoring of ECG signals. It presents a multi-tiered architecture for building PHS and integrating them with enterprise and health information systems. Tiers encompass Body Area Network (BAN) with medical sensors, Personal Server and/or Home gateway, Medical servers and Web Portal....

Recent advances in Information and Communication Technologies (ICT) and more specifically in wireless networks and mobile computing have driven new directions in the development of e-Health sector. New emerging concepts like mobile health (m-Health) and Personal Health Systems (PHS) are expected to revolutionize the way healthcare services are deli...

The paper presents an analysis on data input/output methods, scenarios and standards for radio-communication in body sensor networks (BSN). A comparison of the characteristics of different wireless communication standards, applicable to BSN, in terms of energy consumption is shown. In the second part a use-case scenario for remote monitoring of oxy...

The paper discusses the application of Network Simulator (NS-2) in simulation of Internet-based distributed embedded systems. It envisions the pros and cons of NS-2 as a simulation tool for distributed embedded systems and suggests some design techniques to implement simulation scenarios. At the end, an example of time-delay simulation of switched...

This paper is an attempt to continue development of the multi-tier model for dis- tributed automation systems proposed in previous work. It suggests the use of an open-source Web service application for generation of graphical plots from given data series. The implemen- tation of the service uses the popular open-source tool Gnuplot with capability...

The paper shows some test-bed experimental results on the performance of CoS (IEEE 802.1p) implementation in Controller networks. The experiments are taken out for four different embedded devices with different implementation of TCP/IP stack and communication interface. The communication delay of the packets that is measured between embedded system...

In this paper simulation and analytical results for delay bounding and buffer size in switched Ethernet network are presented. Most of the calculations are made for the environment of Distributed Automation Systems where timing constraints are important. The traffic for the tests is from combined type -- periodic constant bit rate and stochastic wi...

The paper presents an evaluation of a single Web Services Security implementation. The implementation is based on Apache Tomcat2 server and Axis2 toolkit. Evaluation is made for different security mechanism, including transport-level security (SSL/TLS), message-level security – XML encryption and XML digital signatures. Communication delay, encrypt...

The paper presents test-bed experiments for evaluation of Web services implementation for ARM-based embedded system running embedded Linux 2.6. The gSOAP Web services generation toolkit optimized for embedded devices is used. Security is also included in the experiments with the use of SSL/TLS and WS-Security. Two Web services are developed for the...

The paper presents a simulation scenario for performance evaluation of switched Ethernet as communication media in controller networks. Ethernet is the most accepted Local Area Network technology, characterized with low price and deployment robustness. Using Ethernet instead of custom industrial communication protocol can ease the development of ap...

In this paper an abstract model for adaptation of enterprise technologies in heterogeneous networks of small devices is proposed. The model is based on hierarchical multi-tier approach for better manageability and administration. Its structure allows not only separation between business and presentation logic, but also separation of enterprise and...

The paper deals with embedded networking and distributed embedded systems, which is a key area of research over the last years. It presents a custom protocol for data access in embedded devices - CNDEP (Controller Network Data Extracting Protocol). The presented work is based on the presumption that all data exchanged should be encoded in universal...

Test-bed experiments of semi-customized application layer protocol for data extraction in distributed embedded systems are presented. Test-bed network and configuration are built in "Laboratory for Computer Networks and Distributed Systems" in Technical University, branch Plovdiv. The presented experimental results provide a base data for evaluatio...

The paper presents the implementation of a model for Distributed Automation Systems which is experimentally built in the laboratory for Distributed Systems and Computer Networks (http://net- lab.tu-plovdiv.bg/). It discusses the N-tier model and its integration to the filed of distributed automation. The implementation of service-oriented middlewar...

The paper presents the design and implementation of a UDP-based protocol for Distributed Automation Systems. It is based on client/server interactions. Protocol specification is given together with its syntax, grammar and semantics. Message formats, protocol vocabulary and communication rules are described. The possible applications of the protocol...

The paper discusses the design and implementation of a system for distributed measurement. An adaptation of some of the well-proven architecture models and their applicability in distributed measurement is presented. The system's implementation presented is based on open and standardized approaches – Java programming language, standard communicatio...

The paper discusses the applicability of Web services for building distributed automation systems and the benefits they bring. An adaptation of some of the well- proven enterprise architecture models and their applicability in distributed measurement is presented. The presented sample implementation is based on open and standardized approaches - hi...

In this paper a new Web-based multi-tier model for Distributed Automation Systems is proposed. The presented model is constructed for scalability, flexibility and platform independence. Based on the model, integration of automation and business information systems is attained. The model consists of four tiers: Client tier, Presentation tier, Servic...

In this paper, we propose CIGDP (Counter-flow Initiated Generation and Dissemination Protocol), a protocol for dissemination of traffic information in urban traffic networks using a distributed computers architecture approach. Vehicles detect, generate and propagate information without relaying on any existing infrastructure. We focus on the follow...

Nowadays, advanced technology devices are all around us. We take them for granted and we are using them in all spheres of social life. We decided to combine the fast development of the technology and daily human habits in a centralized system that we called "Home Control on Fingertips" (HOCFIT). The system is designed in hierarchical three-layer mo...