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The Realization of NGN Architecture for ASON/GMPLS Network, Journal of Telecommunications and Information Technology, 2011, nr 3
Get PDFFor the last decades huge efforts of telecommunication, Internet and media organizations have been focusing on creating standards and implementing one common network delivering multimedia services – Next Generation Network. One of the technologies which are very likely to be used in NGN transport layer is ASON/GMPLS optical network. The implementation of ASON/GMPLS technology using open source software and its results are the subject of this paper. The ASON/GMPLS architecture and its relation to the proposed ITU-T NGN architecture are described. The concept, functional structure and communication among architecture elements as well as the implementation of laboratory testbed are presented. The results of functional tests confirming proper software and testbed operation are stated
Guaranteed Protection in Survivable WDM Mesh Networks – New ILP Formulations for Link Protection and Path Protection, Journal of Telecommunications and Information Technology, 2011, nr 4
Get PDFIn this paper we propose new simple integer linear programs (ILPs) formulations for minimizing capacity (in wavelength link) utilization in survivable WDM network. The study examines the performance of shared based protection schemes, such as path protection scheme and link protection scheme under single fiber failure. The numerical results obtained show a reduction in capacity utilization using random traffic compared to the reported ILP formulation. We also present the results using Poisson’s traffic to identify the frequently used links for the widely used NSF network. The proposed work not only reduces the wavelength consumption in different traffic scenarios but also efficient in terms of simulation time
Self-Adaptive Differential Evolution with Hybrid Rules of Perturbation for Dynamic Optimization, Journal of Telecommunications and Information Technology, 2011, nr 4
Get PDFIn this paper an adaptive differential evolution approach for dynamic optimization problems is studied. A new benchmark suite Syringa is also presented. The suite allows to generate test-cases from a multiple number of dynamic optimization classes. Two dynamic benchmarks: Generalized Dynamic Benchmark Generator (GDBG) and Moving Peaks Benchmark (MPB) have been simulated in Syringa and in the presented research they were subject of the experimental research. Two versions of adaptive differential evolution approach, namely the jDE algorithm have been heavily tested: the pure version of jDE and jDE equipped with solutions mutated with a new operator. The operator uses a symmetric a-stable distribution variate for modification of the solution coordinates
Evolutionary Algorithm that Designs the DNA Synthesis Procedure, Journal of Telecommunications and Information Technology, 2011, nr 4
Get PDFChemical synthesis of nucleotide chains is very erroneous for long sequences. Often a gene is constructed from short fragments joined with the use of complementary helper chains. The number of possible potential solutions for a long gene synthesis is very large, therefore a fast automated search is required. In the presented approach a modified method of long DNA construction is proposed. A computer program that searches for an optimal solution in the space of potential synthesis methods has been developed. This software uses an evolutionary algorithm for global optimization and a hill- climbing algorithm for local optimization. The long DNA construction method was tested on random sequences. The results are very promising. The next step is to perform experiments in a biotechnological wet laboratory involving DNA strand synthesis using the method designed by the presented software
Incrementally Solving Nonlinear Regression Tasks Using IBHM Algorithm, Journal of Telecommunications and Information Technology, 2011, nr 4
Get PDFThis paper considers the black-box approximation problem where the goal is to create a regression model using only empirical data without incorporating knowledge about the character of nonlinearity of the approximated function. This paper reports on ongoing work on a nonlinear regression methodology called IBHM which builds a model being a combination of weighted nonlinear components. The construction process is iterative and is based on correlation analysis. Due to its iterative nature, the methodology does not require a priori assumptions about the final model structure which greatly simplifies its usage. Correlation based learning becomes ineffective when the dynamics of the approximated function is too high. In this paper we introduce weighted correlation coefficients into the learning process. These coefficients work as a kind of a local filter and help overcome the problem. Proof of concept experiments are discussed to show how the method solves approximation tasks. A brief discussion about complexity is also conducted
IPv6 in Wireless Networks – Selected Issues, Journal of Telecommunications and Information Technology, 2011, nr 2
Get PDFThe article presents issues concerning the construction of autonomous wireless networks based on the IPv6 protocol. Prospects of implementation of IPv6 in wireless networks and IPv6 features and mechanisms important in such applications are discussed. Research directions related to the use of IPv6 in wireless networks are also outlined. Then the selected concepts are described, arising in the course of the EFIPSANS (Exposing the Features in IP Version Six Protocols that can be Exploited/Extended for the Purposes of Designing/Building Autonomic Networks and Services) project, during studies on the autonomy of nodes and routing configuration for wireless networks. Concepts presented here apply to wireless ad hoc mesh networks. Discussed is their nature and aspects related to auto-configuration and autonomously operating routing. In particular, there is a Wireless Autonomic Routing Framework (WARF) architecture presented
GPON, the Ultimate Pertinent of Next Generation Triple-play Bandwidth Resolution, Journal of Telecommunications and Information Technology, 2011, nr 2
Get PDFOptical transmission is getting more popular in the access network due to the increasing demand for bandwidth. New services like IP television (IPTV) transmission, video on demand (VoD) etc. over Internet together along high speed Internet access are confronting the demand of higher bandwidth at the customer end in today’s Ethernet network backbone. Even though today’s well deployed XDSL (i.e., VDSL/VDSL2+, SHDSL) solutions can satisfy bandwidth demand but are limited to the restriction regarding distance. Hereby, the suitable solution for high bandwidth demand with a long reach can be met by reaching optical cable to customer end directly. One of the possible ways would be to install passive optical network (PON). Gigabit PON (GPON) is the far-most advanced PON solution used by European and US providers while providers in Asia predominantly use EPON/GePON. This GPON is the basic technology to support the structure of the next-generation fiber to the home (FTTH) system. This paper provides an overview of such GPON solution associating its network architecture, transmission mechanisms and some key services
Characteristics of Measured Rainfall Rate at Ogbomoso, Nigeria for Microwave Applications, Journal of Telecommunications and Information Technology, 2011, nr 2
Get PDFCharacteristics of rainfall rate useful in the estimation of attenuation due to rain are presented. Rain data collected at Ogbomoso between January–October, 2009 were used in the analysis. Result shows that power law relationship exists between the equiprobable rain rates of two different integration times. The value of conversion factor CE and CR obtained for Ogbomoso are 0.28(60) and 0.64(90) respectively. Our result then shows that different conversion factor is required for different location even within the same climatic region
Rozbieżność celu producenta i konsumenta na przykładzie rynku telekomunikacyjnego w Polsce. Telekomunikacja i Techniki Informacyjne, 2011, nr 3-4
Get PDFArtykuł jest próbą zarysowania problematyki rozbieżności celów konsumenta i producenta w obszarze ekonomiki sektora telekomunikacyjnego w Polsce. Jądrem omawianych zagadnień jest motywacja operatora telekomunikacyjnego (dominującego) do efektywnego działania oraz zaangażowanie go w realizację szerszych celów społecznych
Performance Evaluation of Signaling in the IP QoS System, Journal of Telecommunications and Information Technology, 2011, nr 3
Get PDFThe IP QoS System is based on next generation networks (NGN) and differentiated services (DiffServ) architectures. Its main part is a signaling system, which allows to send a request from a user to the system for establishing new connection with predefined quality of service assurance. In this paper we present trial results of the proposed signaling system. The experiments were performed to measure setup delay utilizing artificial call generator/analyzer. To obtain results we assumed different distributions of interarrival and call holding times based on the literature. The results show that the setup delay strongly depends on access time to network devices, however also on the assumed call holding time models