Natasa Gospic

Improvement of children safety by using RFID based service

Most important characteristics of RFID technology, the way it operates and basic components are presented in the paper with the aim to be used for kids safety. This study shows the proposed implementation of the system solution based on RFID and deployed in school that registers arrival and departure times of pupils and sends that information to parents via SMS and/or e-mail. A survey is conducted among potential users to evaluate a need for implementation of this system in Belgrade schools.

Dynamic guard margin CAC algorithm with ensured QoS and low CDP in heterogeneous wireless networks

This paper proposes a dynamic guard margin algorithm for connection admission control in heterogeneous wireless networks, where UMTS and WLAN systems co-exist in different tiers. The algorithm works based on the idea that a network controller should down-grade the similar or lower Quality of Service (QoS) classes of traffic during the QoS negotiation phase in handovers, instead of rejecting handover connection requests of higher QoS class of traffic. The efficiency of the proposed algorithm is evaluated and compared with the other proposed algorithms using computer simulations. The obtained results demonstrated that the proposed algorithm performs much better than the existing algorithms in terms of resource saving, number of accepted connections, number of rejected connections during handovers, and total resource utilization.

CAC Negotiation Algorithm Proposal for Higher QoS in Heterogeneous Wireless Networks

In this paper novel CAC algorithm has been developed for heterogeneous UMTS-WLAN networks, based on previous existing algorithms and their upgrade with new offers (instead of rejecting call) during QoS negotiation phase in handover. Efficiency of proposed algorithm has been tested in created simulation, and it showed better results in saving resources, more accepted calls, less rejected calls during handover and better resources utilisation.

Broadband Universal Service and Access: Trends and models

This paper addresses the problem of broadband development in Europe and new roles of Universal Service and Universal Access. Review of European Universal Service Obligation and criteria for inclusion of broadband in scope of Universal Service are presented. Based on the EU commission approach, we discussed models for broadband deployment and their decomposition. The aim of these models is to identify the main access gaps and the scope of services to be considered. The proposed model gives possible intervention methods. Financial scheme based on public private partnership is emphasized. The paper proposes that the broadband Universal Service and Universal Access policy should be a part of national broadband plans and agendas.

Yugoslav telecommunications markets: vision and potential

This article deals with the current status and future development plans for the Yugoslav telecommunications infrastructure, markets, and industry. The present trend of liberalization, competition, and globalization of the telecommunication business calls for more consideration of how new challenges will be faced. Several types of telecommunication systems are considered: terrestrial infrastructure, public mobile systems, access networks, data networks, and selected aspects of the Internet.

An approach to assess criticality of elements in the process of information infrastructure protection

In this paper the new approach to assessment an importance/criticality of elements within the critical information infrastructure is presented. The proposed method is based on the identification of critical routes within the network, and the recognition of the most important nodes without using centrality measures and simulation techniques. The elements and their dependencies within the information infrastructure are transformed into a relational topological graph. The elements are presented as the nodes, and the relations between them as the edges of the graph.

Adaptive control of call acceptance in WCDMA network

In this paper, an overview of the algorithms for access control in mobile wireless networks is presented. A review of adaptive control methods of accepting a call in WCDMA networks is discussed, based on the overview of the algorithms used for this purpose, and their comparison. Appropriate comments and conculsions in comparison with the basic characteristics of these algorithms are given. The OVSF codes are explained as well as how the allocation method influences the capacity and probability of blocking.

Measuring the quality of DG CAC per class degradation algorithm

This paper presents quality measures of DG CAC Algorithm, as well as other CAC Algorithms. We have measured the preformance of DG CAC Algorithm in comparison to the other three known algorithms as regards the respect of class quality. Efficiency of the proposed algorithm has been tested in created simulation, and it showed better results in the respect of classes, which indicates better resource utilization and provides justification to use DG CAC in WCDMA networks.

Some aspects of broadband Internet growth and limits

Deployment of Broadband Internet is currently one of the most important global issues. Plans for developing agendas are very ambitious but implementation is not as expected. In this paper authors analyse broadband growth and its limitation factors, delays and gaps. Using logistic growth function, the growth limit, delay and gap for Serbia is calculated in reference to the average of EU countries. Authors selected group of broadband barriers and compared values and gaps between EU and Serbia. Results show that Serbia is lagging behind EU-27 in broadband Internet access, growth is not fast as needed and consequently delay and gaps are significant.

Measuring the Characteristics of DG CAC Algorithm

Users today expect email and instant messaging access, surf, video games and other services through mobile broadband access networks. In order to support this increasing data traffic, advanced resource management has to be implemented. As CAC (Call Admission Control) algorithm plays an important role in this resource management, comparing of two proposed call admission control algorithms has been done in this paper. Algorithms are tested in simulation environment, for two different periods of time. They showed expected characteristics in both 1000 and 10000 seconds periods, and newly proposed DG CAC algorithm showed better results than other algorithm, in number of handover requests, and in the way of returning resources to degraded connections.