Eduard Cristian Popovici

Polytechnic University of Bucharest | UPB · Department of Telecommunications

With the evolution of technology, we are witnessing the development of mobile terminals that are getting closer to a personal computer in terms of features and applications. At the same time, there is an increase in the number of mobile device users, which also leads to an increase in the use of online shopping or finance management applications. H...

The latest technologies advancement in NLP (Natural Language Processing) solution allows developing innovative tools that enrich customer experience with products and services. Contact Center environments gradually adopted real-time analytics solutions, and latest research is focusing on how to integrate social media channels. Based on the work mad...

The increasing processing power that personal computers have nowadays determined an accelerated evolution of the quality of video games regarding the graphic details, sound effects and simulation of physical phenomena. All these improvements aim to present a more realistic world in the game, such as Asseto Corsa, a racing car simulator that aims to...

Recent technological advances in the telecommunications industry have led to discovering the limitations of traditional communication networks and, in this context, to the emergence of a new paradigm that tries to mitigate them, namely Software Defined Networking (SDN). When it appeared, it was associated only with the OpenFlow protocol, as a south...

Nowadays, the internet is playing a major role in everyday life, becoming the first choice for sharing information. In the last sixteen years the number of websites increased from three million to almost one billion. An important contribution to this number was brought by the content management systems which provided an easy approach for any user t...

In the process of designing and manufacturing an electronic system the digital oscilloscope plays an essential role but it also represents one of the most expensive equipment present on the typical workbench. In order to make electronic design more accessible to students and hobbyists, an affordable data acquisition system was imagined. The paper e...

The networking industry faces nowadays with the emergence of a somewhat revolutionary paradigm that is intended to rethink network architectures, with the intention to mitigate the limitations that appeared in the traditional networks: Software Defined Networking (SDN). This paper illustrates differences between some SDN controllers, which represen...

Current and future developments in our society changes the way people and machines interact, leading to more possible breaches in a person's " trust circle ". Since the development of communication networks, of the Inter-net, devices tended to become more and more interconnected, more conscious of one and another, in order to meet user's demands. Y...

This paper proposes an enhanced approach for implementation of Media Independent Handover (MIH) information services (MIIS) based of the combination of a hierarchy of information servers and prediction of next point of attachment (PoA). While other recent proposals were validated only by simulations, we evaluated the implemented system with a real...

Our keystroke-based user identification system represents a minimal implementation of a software system that can be used for continuous authentication of users, based on their keystroke dynamics. This paper brings into evidence the role of an alerting subsystem as a part of the software system mentioned above. Also, the paper presents a basic imple...

In this paper we propose several solutions to combine the use of two algorithms for patterns recognition and user validation, both intended to be used in the same time to improve the overall performance of the validation process in a continuous authentication system based on keystroke dynamics. The first one is based on a Multi Layer Perceptron (ML...

In this paper we introduce a continuous authentication system based on keystroke dynamics (BIOMETRIC). We also propose two algorithms for extracting patterns and validating the user, both intended to be used in the same time to improve the overall performance of the validation process. The first one is based on a Multi Layer Perceptron (MLP) Neural...

The effects of the coexistence of different wireless access technologies in the same area are not very easy to be evaluated and analysed. If these different networks interact with each other and form a heterogeneous wireless network, the analysis becomes even more difficult. Different approaches are possible: to build a pilot heterogeneous network...

The paper describes a video streaming application build to evaluate session continuity over wireless hybrid access networks in vertical handover (VHO) conditions. The results showed us which components have to be improved. Further developments will address these improvements.

In this paper we describe a media streaming application build to test a system which implements the IEEE 802.21 Media Independent Handover (MIH) standard, for interoperability between wireless hybrid access networks. We evaluated the real-time performance of our vertical handover prototype system by means of the audio streaming continuity assessmen...

Multiuser detection technique implies joint demodulation of overlapping data streams of data sent by different users, improving their individual performances based on the knowledge of some key parameters of all users. Each user is identified by its own signature code, which should be, in the ideal case, orthogonal on all the others. Several multius...

In this paper we describe a context-aware reconfigurable system, which implements the IEEE 802.21 Media Independent Handover (MIH) standard for interoperability between wireless hybrid access networks. The proposed approach uses vertical handover prediction algorithms to improve the resource management decisions, through access to our Web Service i...

During the last years, software applications performing scenarios related to vertical handovers were revealed. However, the great majority of these demonstrators were designed and optimized for multimode notebooks, having a fair amount of processing power. This article aims to describe on how to implement and optimize the main components of the IEE...

This paper presents a geographically distributed mobile teamwork management system that combines the simplicity of Web services architecture and protocols, with the GPS-based location information retrieval, and a geographical mapping application. The aim of our work is to offer a Web-based client-server system heading towards a better management of...

In this paper we present a software demonstrator, for a system built following the directions described in the IEEE 802.21 (Media Independent Handover) standard, capable of completing an independent vertical handover. We first bring in front the field's related work, and also propose methods of implementing the components described in the standard....

This paper describes the road of RIWCoS architecture for reconfigurable interoperability and service continuity in wireless hybrid communications: from the IEEE 802.21 MIH standard, through generic modules design and specification, toward implementation and integration. Given the results obtained during the development of the prototype demonstratin...

When developing a network management system, the developer is faced with many choices concerning how to interact with the network resources and how to embed into the schema of manager agent architectures. In this paper we propose NMX (Network Management Extensions), a software framework implementation based on Java JMX (Java Management Extensions)...

This paper describes a solution for implementing the Media Independent Information Service, later referred to as MIIS, described in IEEE 802.21 standard. First we present the previous work towards defining a complete system capable of realizing a vertical handover according to the standard. Next we detail the MIIS general architecture, the informat...

In this paper we describe the design and implementation details of a mobile application supporting news access and virtual community interactive services, based on open technologies such as Java programming language, Java Mobile Edition (Java ME) libraries, MySQL database and an open Web server. The goal was to create an easy to use, mobile, intera...

This paper provides a view on the developing process of the Media Independent Information Service, later referred as MIIS, described in the IEEE 802.21 standard. The first chapter describes our related work on this standard, and it's relationship with the MIIS entity. The following chapters present the general architecture of the system, some aspec...

In this paper we propose a software module for continuously monitoring a wireless network card, able to handle and rise IEEE 802.21 compatible primitives in support for vertical handover in heterogeneous networks. This module is intended to be installed on a multimod mobile terminal, and will automatically monitor and switch the connection link, wh...

The paper describes the main issues regarding the interoperability between some representative wireless access networks and the corresponding vertical handover in wireless hybrid access networks. The proposed approach conforms to the IEEE 802.21 media independent handover (MIH) standards.

In this paper we describe the architecture and implementation details for a software system supporting session mobility at application level, based on standard SIP protocol. The target of our work is to build a more complex reconfigurable system with support for vertical handover in hybrid wireless networks. The presented system is a step toward th...

In this paper we described the generic design of software interoperability modules for vertical handover in wireless hybrid access networks. The proposed approach conforms to the IEEE 802.21 Media Independent Handover (MIH) standard and fits into our architecture for reconfigurable interoperability of wireless communication systems, RIWCoS. The nex...

In this paper, the architecture of a software module that can support vertical handover in heterogeneous networks is presented. The proposed approach, is capable of supporting 802.21 link layer events and commands, and represents the start-up point for building a system compatible with the standard, that can be integrated in mobile terminals applic...

In this paper we evaluated the impact of high network load and congestion on voice quality. In our studies we used OPNET’s IT Guru Tool as a simulation framework. We analyzed the QoS performance of six speech coding schemes in different network conditions: congested network, network with high utilization without congestion, and network with a very...

In this paper we described the design and some implementation issues for software interoperability modules in multiaccess terminals. The proposed solution uses an intermediate link layer driver which can provide independent access to link layer. The interoperability modules construed around this driver serve as a basis for a 802.21 Media Independen...

Distributed multimedia applications such as conference and collaborative applications require an appropriate conference management. Close group conferences like meetings, discussions, tele seminars, or consultations need a strictly controlled group membership. Current conference systems achieve this by using a centralized group server as specified...