Bojan Bakmaz

Network Selection Algorithm for Heterogeneous Wireless Environment

Service delivery in a heterogeneous wireless environment requires the selection of an optimal radio access network. In order that users could be always connected through the optimal network, it is necessary to develop an adequate model for its selection. This paper presents the proposal of optimal network selection algorithm in wireless heterogeneous environment that is based on TOPSIS method when solving the multicriteria analysis. The wireless networks in this model represent the alternatives, while the network parameters (available bandwidth, quality of service level, security level, data transfer cost) are considered as the criteria for determining the optimal network.

Wireless Multimedia Communication Systems: Design, Analysis, and Implementation

Rapid progress in software, hardware, mobile networks, and the potential of interactive media poses many questions for researchers, manufacturers, and operators of wireless multimedia communication systems. Wireless Multimedia Communication Systems: Design, Analysis, and Implementation strives to answer those questions by not only covering the underlying concepts involved in the design, analysis, and implementation of wireless multimedia communication systems, but also by tackling advanced topics such as mobility management, security components, and smart grids. Offering an accessible treatment of the latest research, this book: Presents specific wireless multimedia communication schemes that have proven to be useful Discusses important standardization processing activities regarding wireless networking Includes wireless mesh and multimedia sensor network architectures, protocols, and design optimizations Highlights the challenges associated with meeting complex connectivity requirements Contains numerous figures, tables, examples, references, and a glossary of acronyms Providing coverage of significant technological advances in their initial steps along with a survey of the fundamental principles and practices, Wireless Multimedia Communication Systems: Design, Analysis, and Implementation aids senior-level and graduate-level engineering students and practicing professionals in understanding the processes and furthering the development of todays wireless multimedia communication systems.

Internet Protocol Multimedia Subsystem for Mobile Services

This work describes the support for Internet protocol multimedia subsystem (IMS) in mobile communication services. An architecture for accessing multimedia services together with IMS layered service is presented. IMS within universal mobile telecommunication system (UMTS) core network is analyzed, too. The second part deals with an approach for the interoperability between IMS and Web services within the IMS domain through the session management techniques, based on the existing session initiation protocol (SIP) management mechanism.

Network selection in heterogeneous environment: A step toward always best connected and served

Service delivery in a heterogeneous wireless environment requires the selection of an optimal access network. In order for users to be always connected through the optimal available network, it is necessary to develop an adequate technique for its selection. This paper deals with network selection concept as a perspective approach to the always best connected and served paradigm in heterogeneous wireless environment. It provides a survey on fundamental aspects of network selection process and mainly focuses on decision making mechanisms. After presenting the related standards, the perspective vertical handover approaches from the open literature are analyzed and compared. The paper concludes with a case study related to the influence of traffic conditions on network selection, which reveals the advantages of the always best connected and served concept.

Mobile Broadband Networking Based on IEEE 802.20 Standard

In the near feature, mobile applications development will gradually become an interesting research field from the IP structure point of view. In connection with this, a survey of the emerging IEEE 802.20 standard is presented. This paper also provides the technical aspects as well as the system architecture of the IEEE 802.20. The comparison with other similar standards like 802.16e is given, too. An example for invoking this standard in the broadband network is emphasized.

Research challenges for 5G cellular architecture

Due to the centralized architecture of current cellular networks, the wireless link capacity as well as the bandwidth of the radio access and backhaul networks cannot practically cope with the exponential growth of mobile traffic. In order to meet this challenge, researches on the fifth generation (5G) cellular systems are highly anticipated in the next decade. Advanced technologies such as massive antennas and millimeter-wave systems, as well as direct communications will have significant impact on design of new heterogeneous network architecture. Cloud computing has emerged as a promising solution for providing high energy and spectral efficiency across software defined radio networks, in which the virtualization of communication hardware and software elements place stress on architecture and protocols. This paper analyses the main challenges raised by the new vision of cellular architecture, particularly focusing on issues related to the key emerging radio technologies, direct communications, cloud computing, as well as support of massive access.

Electrical Engineering Hall of Fame: Originator of Teletraffic Theory [Scanning our Past]

This article takes a look at the professional accomplishments of Danish scientist Agner Krarup Erlang, who made pioneering contributions in teletraffic theory development.

Traffic models with changed serving intensities in secondary and ternary groups

In this paper the primary group with two Poisson traffics is considered whereupon the rejected calls from one of them are directed to the alternative groups and served with changed serving intensity. The generating function technique is used for the analytical solving model with secondary and ternary groups. The obtained analytically solutions essentially reduce constraint concerning the equation system sizes, convergence and calculation time, which exists during numerical solving the steady state system equations. For the case with single channel in ternary group, explicit solutions for traffic parameters are obtained. Comparison with the model which has the unique serving intensity of overflow traffic is carried out.

Security aspects in future mobile networks

This paper deals with the problem of security aspects in future mobile networks. Security is important to be recognized in mobile networks for current and future users and implements. In the first par of this presentation, security concepts together with infrastructure security are presented. Five security features groups are emphasized. The second part treats the problem of security context together with network operatorpsilas security requirements. Tree groups of security requirements i.e. from userpsilas, networkpsilas and servicepsilas perspective are pointed out.

Hamming Window to the Digital World

Inspired by the awarding of the 30th jubilee IEEE medal “for exceptional contributions to information sciences and systems,” this article is dedicated to the memory of Richard W. Hamming, mathematician and computer scientist. If Shannon’s mathematical theory of communication, including coding, entropy, and channel capacity, can be assumed as cornerstone of the digital world, error-detecting and error-correcting codes, at the same time, pave the way to its redundancy and reliability. The role of the interaction between human and computer in the world of contemporary communication is considered, together with an emphasis on Hamming’s fundamental contributions from information theory to computer technology. Hamming code, Hamming distance, Hamming metric, Hamming window, Hamming numbers, and sphere packing are now standard terms that reflect him as a leader in the development of coding theory. His ideas in coding theory continue to have practical use in computer design.