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PL
Artykuł przedstawia mechanizm bypass dla problemu natłoku w warstwie IP sieci IP/EON. Rozważany problem natłoku dotyczy ruchu pomiędzy centrami danych. W ramach badań przeprowadzono eksperymenty symulacyjne z użyciem topologii NSF15. Dokonano pomiarów w sieci IP/EON z i bez mechanizmu bypass. Wyniki wykazują zysk w postaci zmniejszonego prawdopodobieństwa blokady przepustowości sieci przy równoczesnym skróceniu trasy rutingu w warstwie IP dla mechanizmu bypass.
EN
The paper introduces a bypass mechanism to solve congestion problem at the IP layer in IP / EON networks. The congestion problem concerns traffic between data centers. Simulation experiments were carried out using the NSF15 topology for IP/EON networks with and without the bypass mechanism. The obtained experimental results show that implementation of the proposed mechanism can reduce bandwidth blocking probability with cut length of IP routes.
PL
Artykuł przedstawia model wielowarstwowej współpracy sieci IP z elastyczną siecią optyczną (model IP/EON). Model IP/EON zakłada alokację zasobów elastycznej sieci optycznej dla zgłoszeń odrzuconych w warstwie IP. Model IP/EON porównano z transmisją w warstwie IP. Analiza wyników z przeprowadzonych symulacji dla dynamicznego scenariusza pracy sieci wykazuje zysk w postaci poprawy jakości transmisji danych w sieci dla proponowanego modelu IP/EON.
EN
In this paper a multilayer model of IP transmission over elastic optical networks is proposed (model IP/EON). In the proposed IP/EON model, elastic optical resources are assigned to requests which cannot be served at the IP layer. The IP/EON model is compared with transmission at the IP layer. Analysis of simulation results for the dynamic network scenario shows that the implementation of the IP/EON model improves data transmission in networks.
EN
The introduction of flexible frequency grids and advanced modulation techniques to optical transmission, namely an elastic optical network, requires new routing and spectrum allocation techniques. In this paper, we investigate dynamic two-step routing and spectrum allocation (RSA) methods for elastic optical networks. K-shortest path-based methods as well as spectrum allocation methods are analysed and discussed. Experimental verification of the investigated techniques is provided using simulation software. Simulation results present effectiveness of routing and spectrum allocation methods for analyzed networks using requested bandwidth of connections. Moreover, performance of shortest path first methods improves considerably when a number of candidate paths increases in the UBN24 topology.
PL
Podczas dynamicznej pracy elastycznej sieci optycznej, nieodpowiednio wybrany zakres widma alokacji powoduje wzrost prawdopodobieństwa odrzucenia nadchodzących do sieci zgłoszeń. Artykuł przedstawia metodę alokacji zasobów widmowych ścieżki rutingu. Przeprowadzone symulacje dla dynamicznej pracy elastycznej sieci optycznej wykazują zysk zmniejszonego prawdopodobieństwa blokady dla proponowanej metody. Modyfikacja metody alokacji ścieżki o najmniej zajętym widmie łączy zmniejsza wykorzystanie zasobów w sieci.
EN
In dynamic elastic optical networks, improperly spectrum allocation increases the probability of rejected incoming network requests. The article presents allocation of routing path’s spectrum. The proposed spectrum allocation method is evaluated in dynamic elastic optical networks. Simulation results indicate reduction of bandwidth blocking probability in networks with presented method. Next, Most Slot First path selection policy is modified to achieve better spectral efficiency.
5
Content available Elastyczne sieci optyczne
PL
Artykuł przybliża koncepcję elastycznej sieci optycznej i charakterystyczne zagadnienia związane z jej implementacją. Przedstawiono w nim standardy styków optycznych sieci Ethernet 40 Gbit/s i 100 Gbit/s zawarte w dokumencie IEEE 802.3ba. Następnie opisano szczelinowy charakter widma elastycznej sieci optycznej, porównując ze sztywnym podziałem częstotliwości DWDM. Nakreślono problem planowania i dynamicznej alokacji zasobów w sieci.
EN
The paper studies a novel concept of elastic optical network and selected network–level requirements of next generation optical networks. It investigates new optical IEEE 802.3ba Physical Layer Specification. Next it is compared the fixed-grid wavelength division multiplexing optical networks with flexible-grid elastic optical networks. It is important to define routing and spectrum assignment RSA algorithms, which are required for network planning and dynamic resource allocation. Mobile lab, radiocommunication services testing, radiocommunication networks measurements.
EN
The development of tourism in Poland demands emphasizing the richness of tourism products. The tourism in postindustrial as well asp geologically differentiated areas may develop tourism and recreation in all regions of the country. Examples and successes in this range in many regions in Europe, and also in Poland, indicate this direction of development.
7
EN
Unique natural and environmental advantages are characteristic of the areas neighbouring the eastern border of Poland. They are peculiarly predisposed to rapid development of tourism and recreation in compliance with principles of sustainable development and accepted solutions contained in Rural Development Program in Poland 2007-2013.
EN
In his paper some information connected with possibilities of managing areas degraded by coal mining in favour of afforestation and recreation grounds is presented.
EN
The aim of paper was to determine content of Pb in soils under different impact of anthropopressure. The lead contents were determined in 22 soil samples from southern and central Poland. For lead determination in soil samples the GFAAS technique was used. The Pb contents in soil samples from GOP region were 16,0-187 mg·kg-1. The Pb contents in soil samples from Węgrów region and Nadarzyn region were respectively 4,9-15,6 mg·kg-1 and 4,4-24,5 mg·kg-1. Results of our research are confi rming the negative infl uence of anthropopressure on the content of lead in the surface horizon of soils.
10
Content available remote Chrom, nikiel i ołów w wierzchniej warstwie gleb aglomeracji warszawskiej
EN
Results of domestic and foreign research are showing the negative influence of urban agglomerations on physicochemical properties of urban soils particularly for the accumulation of heavy metals. The aim of research was determining differences of chromium, nickel and lead contents in upper layer of soils from agglomeration of Warsaw and area regarded as athropogenically unchanged and comparing with permissible values stated in standards of the soils quality. Results of the research are pointing both the bigger the content of chromium, nickel and lead as well as salinity in upper layer of soils of Warsaw agglomeration in comparing to area of Kabacki Forest. Maximum value of examined heavy metals did not exceed permissible value stated in standards of the soils quality contained in the Directive of Ministry of the Environment.
11
Content available remote Kadm i selen w glebach pod zróżnicowanym wpływem antropopresji
EN
The aim of the presented paper was to determine content of Cd and Se in soils under different impact of anthropopressure. The cadmium and selenium contents were determined in 18 soil samples from southern and northeastern Poland. For cadmium determination in soil samples the GFAAS techniąue was used and the HGAAS technique for selenium determination. The Cd contents in soil samples from region under strong impact of anthropopressure were 4,6-64,0 mg·kg-1. The Cd contents in soil samples from region regarded as natural were 1,4-3,2 mg·kg-1. The Se contents in soil samples from region under strong impact of anthropopressure were 0,060-0,818 mg·kg-1. The Se contents in soil samples from region regarded as natural were 0,108-1,570 mg·kg-1.
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