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1
Content available remote Routing protocols in mobile ad-hoc networks
EN
There were more than 8.6 billion mobile devices in the world in the 2019. To be available is imperative in modern society, both in business and in private life. There are mobile networks available on airports, hotels, restaurants, libraries but sometimes we have to make a quick, mobile network on open area for educational campus or military purposes, where there are no mobile operators and public networks such as GSM. A different model of mobile networks is created and called Mobile Ad-hoc Network. The problem of routing is basically the problem of finding the shortest path between nodes. This paper deals with various routing protocols in MANET and shows how to choose the best one for specific purpose.
PL
Na świecie jest ponad 8.6 miliardów bezprzewodowych urządzeń mobilnych I olbrzymia lic\ba sieci. Żeby rozwiązać problemy komunikacyjne trzeba korzystać z metod jak najszybszego I najkrótszego połączenia miedzy węzłami. W artykule analizowano najlepsze sposoby routingu.
EN
Energy and latency are the significant Quality of Service parameters of ad hoc networks. Lower latency and limited energy expenditure of nodes in the ad hoc network contributes to a prolonged lifetime of the network. Reactive protocols determine the route to the destination using a route discovery process which results in increased delay and increased energy expenditure. This paper proposes a new technique of route discovery, Dynamic Blocking Expanded Ring Search (DBERS) which minimizes time delay and energy required for route discovery process. DBERS reduces energy expenditure and time delay occurring in the existing route discovery techniques of reactive protocols. The performance of DBERS is simulated with various network topologies by considering a different number of hop lengths. The analytical results of DBERS are validated through conduction of extensive experiments by simulations that consider topologies with varying hop lengths. The analytical and simulated results of DBERS are evaluated and compared with widely used route discovery techniques such as BERS, BERS+. The comparison of results demonstrates that DBERS provides substantial improvement in time efficiency and also minimizes energy consumption.
PL
System łączności bezprzewodowej jest budowany z wykorzystaniem szerokopasmowych radiostacji definiowanych programowo, których zadaniem jest tworzenie ad-hoc sieci szkieletowych IP dla użytkowników poruszających się na pojazdach. System zapewnia ochronę informacji w warstwach transmisji, sieci i komunikacji, gdzie zastosowano mechanizmy kryptograficzne dedykowane na potrzeby budowania różnych domen. Podsystem zarządzania radiostacjami i kryptografią umożliwia planowanie, zarządzanie i zbieranie doświadczeń z misji.
EN
The wireless communication system is built with wide band software defined radios (SDR) in order to create ad-hoc IP network for users moving on vehicles (MANET). This system provides TRANSEC, NETSEC and COMSEC protection with cryptographic mechanisms dedicated to national, allied and coalition needs. The radio and cryptography management subsystem enables planning, management and collecting mission experiences.
EN
Now is the age of information technology. World is advancing day by day. At present in this progressing world communication from one place to another has become so easy, less costly, and faster. This modern life is almost impossible with the help of these communication technologies. People need to talk, need to share data, need to express their emotion from long distance. So they need to use technologies to communicate with one another. Nowadays the fields of MANET have yielded more and more popularity and thus MANET have become a subject of great interest for the researchers to enforce research activities. Mobile Ad Hoc Network (MANET) is the cooperative engagement of a collection of mobile nodes without the required intervention of any centralized access point or existing infrastructure. There is an increasing trend to adopt mobile ad hoc networking for commercial uses. Mobile Ad Hoc Network (MANET) is an emerging area of research to provide various communication services to the end users. But these communication services of Mobile Ad Hoc Network (MANET) use high capacity of bandwidth and a big amount of internet speed. Bandwidth optimization is indispensable in various communications for successful acceptance and deployment of such a technology. Thinking of this, I propose a New Bandwidth Optimization Technique that Enhance the Performance of Mobile Ad Hoc Network (MANET). The new Bandwidth optimization technique which is more efficient in terms of time delay in Mobile Ad Hoc Network (MANET) can redirect a new way towards optimization development in network communication and device junction technology.
5
Content available remote Analysis and assessment of power consumption for routing protocols in MANET
EN
Recently, the lack of independent wireless networks deployment was the main reason not only loosing victims but also diminution of the performance of security forces and first aids services during natural disasters and wars. Mobile Ad Hoc Networks (MANET) is the technology of choice used in such critical situations where the infrastructure of wireless networks fails to work. MANET relies on its nodes to forward and route packets that gives it a characteristic of an independent network. The independence here means that the network relies on its battery power to achieve its routing. In this research work, we study two types of MANET protocols belonging to different kinds of routing protocol categories: namely reactive protocol and proactive protocol in terms of power consumption. More specifically, we are interested on the Destination-Sequenced Distance-Vector (DSDV), Optimized Link State Routing (OLSR), Ad Hoc On-Demand Distance-Vector (AODV) and Dynamic Source Routing (DSR) protocols to investigate how much power they consume at different layers, operation modes, routing overhead and MAC load. In order to achieve the goal of performance study, we choose some scenarios that can be adapted to different MANET contexts: such scenarios carried out when network area size, network density, pause time and mobile node speed are changing. Extensive simulations and results for these scenarios obtained by NS2 simulation software.
EN
Efficient access to the spectral resources becomes a challenge for future military wireless communication systems. It requires spectral situation awareness, knowledge of current regulations, local policies and hardware platform limitations. It can be achieved by cognitive radios, realizing cognitive cycle, consisting typically of continuous observation, orientation, reasoning and decision making. All these elements must be realized in parallel and shouldn't interfere with each other. Even more difficult issue is related with cooperation between different nodes, especially in wireless domain, in harsh propagation conditions. Unpredictable phenomena create hard conditions for all deterministic behavior models, and their reproduction is a key element for efficient operation of the network. Very popular computer simulations are always simplified, and real time implementation gives an opportunity to make the next step in system elaboration. This paper presents a real-time demonstrator of cognitive radio network. It can work both in wired mode, using radio channel emulator and in mobile mode, to verify influence of real conditions on proposed cognitive solutions and assess their effectiveness.
EN
The article presents an assessment of the maximum Hello period value required for maintaining the assumed network awareness in the context of available transmitter power, number of nodes and their velocity. The Lowest ID algorithm was used for defining the node functions. This problem is especially important for low density and high mobility networks. Assuming that 1% of network nodes have the wrong knowledge about their states, the length of the Hello period in a typical system behavior cannot be higher than 0.1 to 0.5 seconds.
PL
W artykule przedstawiono szacunek czasu powtarzania wiadomości Hello, który zapewnia założony poziom świadomości sieci. W ocenie wzięto pod uwagę zmienność mocy nadawania węzłów, ich prędkość przemieszczania się oraz liczbę. Badania przeprowadzono przy wykorzystaniu algorytmu klasteryzacji Lowest ID. Prezentowany problem jest szczególnie ważny dla sieci mobilnych o małej gęstości. Ocenia się, że dla typowych zastosowań czas powtarzania wiadomości Hello nie powinien być dłuższy niż 0,1 do 0,5 sekundy.
PL
W artykule dokonano oceny wpływu metryki łącza na efektywność mechanizmu routingu w mobilnej sieci ad-hoc z protokołem OLSR. Badania przeprowadzono w warunkach rzeczywistych z wykorzystaniem węzłów na bazie laptopów z kartami Wi-Fi oraz protokołem OLSRv2. Przedstawiono wyniki badań z uwzględnieniem zależności między szybkością transmisji, metryką łącza i metryką trasy. Zaproponowano modyfikację metody szacowania metryki łącza w taki sposób, aby mechanizm routingowy preferował trasy z łączami o większej przepływności.
EN
This paper presents the evaluation of the link metric influence on the routing mechanism performance in mobile ad-hoc networks based on the proactive Optimized Link State Routing (OLSRv2) protocol. The experiments were carried out in real environment with radio nodes based on Wi-Fi equipment and OLSRv2 implementation. The results were discussed and a new approach to the link metric assessment was presented. In our proposal the link metric includes the data rate and the number of the packets received, although fast links are preferred.
PL
Mobilne sieci ad hoc (MANET) są coraz częściej wykorzystywane do wspierania akcji ratunkowych. Przykładem sytuacji, w której użycie sieci MANET może znacznie zwiększyć wiedzę o zagrożeniu jest wyciek gazu ciężkiego. Jednocześnie często zewnętrza infrastruktura komunikacyjna jest niedostępna w strefie zagrożenia. W artykule zaproponowano zarówno zdecentralizowaną metodę wykrywania granicy obszaru pokrytego gazem ciężkim, jak i metodę wyznaczania maksymalnej odległości między parą węzłów, która umożliwia im wzajemną komunikację.
EN
Mobile ad hoc networks (MANET) become increasingly popular in supporting rescue operations. An example of a situation in which the use of MANET network can significantly increase awareness about the hazard is a heavy gas leakage. In the hazardous area often the external communication infrastructure is not available. In this paper both a decentralized method for detecting the border of area covered with heavy gas and the method for determining the maximum distance between a pair of nodes, which enables them to communicate with each other are proposed.
10
Content available An Improved Greedy Forwarding Scheme in MANETs
EN
Position-based routing protocols are widely accepted efficient solution for routing in MANETs. The main feature of position-based routing protocols is to use greedy forwarding methods to route data. The greedy forwarding methods select a node, either having maximum progress towards destination (distance-based principle) or minimum deviation with line between source and destination (direction-based strategy). The first method minimizes the hopcount in a path and on the other hand, second method minimizes the spatial distance between source and destination. The distance-based routing has a great impact on the selection of reliable node and the direction based routing plays a major role to increase the stability of route towards destination. Therefore, in this paper authors propose a weighted forwarding method, which combines both the selection, schemes to select an optimal next forwarding node in a range. The simulation results show that the proposed scheme performs better than existing position-based routing protocols.
11
Content available The channel for hidden data transmission in WSN
EN
This paper describes an idea and realisation of hidden data transmision using Tiny Aggregation Covert Channel (TAGCC) in Wireless Sensor Networks. Our solution uses data aggregation mechanism called Tiny Aggregation (TAG). The protocol is based on idea of hidden messages sending without generate additional data packets and encryption. The paper describes details of proposed algorithm and simulation results obtained during testing of the sensor networks with hidden channel TAGCC.
EN
This paper presents the Reliable Bidirectional Control Protocol (RBCP) protocol, which is a transport protocol for Wireless Sensor Networks (WSN), focused on managing sensors' behaviour. It aims to be a utility for reliable control data transferring from source to destination unit in the network. Considering the related studies on transport protocols, which are mostly dedicated to a single-direction reliable data transport, RBCP is the answer for the lack of control mechanisms in WSNs based on bidirectional communication. The first part of this paper is focused on general presentation of the proposed solution. In the next part, evaluation of the idea and final functionality are discussed. It will finally show the results of undergone testing stage.
PL
Praca dotyczy zagadnień związanych z symulacją mobilnych sieci ad-hoc (MANET). Sieci tego typy odgrywają coraz większą rolę w zastosowaniach cywilnych i wojskowych, w tym w monitorowaniu środowiska i wspieraniu akcji ratunkowych. Zakładając możliwość sterowania ruchem urządzeń tworzących sieć, autor zaproponował algorytm i przedstawił wyniki symulacji formowania mobilnej sieci ad-hoc z wykorzystaniem modelu ruchu węzłów PFM.
EN
This article addresses issues associated with simulation and application of wireless, mobile, and ad-hoc networks (MANETs). Mobile self-organizing ad hoc networks can enhance the capability to coordinate the emergency actions as well as monitor contaminated areas, explore unmanned space, inspect and control working environments. Modeling and simulation are widely used in the design and development of wireless ad hoc networks. The focus is on wireless transission and mobility models. A novel algorithm for wireless sensor network deployment is introduced.
PL
Sieci MANET są coraz częściej wykorzystywane do monitorowania środowiska w sytuacjach kryzysowych. W sytuacjach tych często dochodzi do zniszczenia, awarii lub przeciążenia istniejącej infrastruktury komunikacyjnej. Stąd potrzeba zagwarantowania możliwości komunikacji między węzłami w ramach sieci w czasie jej działania. W niniejszej pracy zaproponowano nową metodę utrzymania spójności sieci. Ważnym aspektem pracy jest minimalizacja wpływu metody na wydajność sieci MANET podczas monitorowania środowiska w różnych scenariuszach. Metoda została zweryfikowana przy pomocy oprogramowania symulacyjnego MobASim w scenariuszu wycieku gazu ciężkiego.
EN
MANETs are increasingly used to monitor environments in emergency situations. In these cases destruction, failure or overload of the existing communication infrastructure often happen. Hence, the necessity to ensure the communication between nodes within the network during deployment occurs. In this paper a new method for maintaining coherence of the network is proposed. An important aspect of the method is minimizing impact on MANET’s performance while monitoring the environment in various scenarios. The method was verified with simulation software MobASim in the scenario of a heavy gas dispersion.
PL
Efektywność sieci MANET w dużej mierze uzależniona jest od funkcjonowania w niej routingu. Mechanizm ten rozpoznaje topologię sieci, a następnie zestawia trasy do wezłów, często w warunkach dużej dynamiki zmian topologii. Prowadzi to do częstych przerw łączności, a w efekcie do opóźnien i strat danych. W artykule przedstawiona została koncepcja routingu z predykcją powiązań pomiędzy węzłami sieci. Rozwiązanie to pozwoli na wcześniejszą reakcję routingu na zmiany topologii oraz podjęcie działań utrzymania ciągłości tras. W artykule przedstawiono równieżwyniki testów symulacyjnych pomiarów czasów powiązań.
EN
The MANET network efficiency largely depends on the routing mechanism. This mechanism recognizes network topology, and than sets the routes to nodes, often under high topology changes. It leads to communication interruptions and consequently to delays and data loss. The article presents the concept of routing with nodes connection prediction. This solution allows for early response to topology changes and to take action to maintain routes continuity. In article also are presented the results of the connections time measurements’ simulation tests.
PL
W artykule zaprezentowano mechanizm RELQA-OLSR (ang. REsources and Link Quality Aware OLSR) rozszerzający RESA-OLSR (ang. RESources Aware OLSR) o metrykę jakości łącza radiowego. Mechanizm uwzględnia obciążenie węzła ruchem i stan baterii do odwzorowania parametru Willingness oraz bierze dodatkowo pod uwagę jakość łącza radiowego ocenianą na podstawie SNR (ang. Signal to Noise Ratio). Przedstawiono wyniki badań symulacyjnych i dokonano oceny wydajności mechanizmu na podstawie czasu życia sieci oraz liczby dostarczonych pakietów.
EN
This paper presents the RELQA-OLSR (REsources and Link Quality Aware OLSR) extending RESAOLSR (RESources Aware OLSR) with link quality metric. This mechanism takes into account the node performance metric with respect to the local resources, i.e., the battery level and the available bandwidth and also the link quality expressed by the level of the received SNR (Signal to Noise Ratio). Simulation results confirmed that the RELQAOLSR mechanism extends the network lifetime and increases the network reliability.
EN
In literature, varieties of topology and geographical routing protocols have been proposed for routing in the MANETs. It is widely accepted that the geographical routings are a superior decision than topological routings. Majority of geographical routing protocols assume an ideal network model and choose the route that contains minimum number of hops. However, in reality, nodes have limited battery power and wireless links are additionally unreliable, so they may highly affect the routing procedure. Thus, for reliable data transmission, condition of the network such as link quality and residual energy must be considered. This paper aims to propose a novel multi-metric geographical routing protocol that considers both links-quality and energy metric along with progress metric to choose the next optimal node. The progress is determined by utilizing greedy as well as compass routing rather than pure greedy routing schemes. To combine these metrics, fuzzy logics are used to get the optimal result. Further, the protocol deals with “hole” problem and proposes a technique to overcome it. Simulations show that the proposed scheme performs better in terms of the packet delivery ratio, throughput and residual energy than other existing protocols.
EN
This paper addresses issues concerned with design and managing of monitoring systems comprised of mobile wireless sensing devices (MANETs). The authors focus on self-organizing, cooperative and coherent networks that maintain a continuous communication with a central operator and adopt to changes in an unknown environment to achieve a given goal. The attention is focused on the development of MANET for heavy gas clouds detection and its boundary estimating and tracking. Two strategies for constructing the MANET are described, in which sensors explore the region of interest to detect the gas cloud, create temporary network topology and finally, cover the cloud boundary, and track the moving cloud. The utility and efficiency of the proposed strategies has been justified through simulation experiments.
EN
Delay and Disruptive Tolerant Networks (DTN) are relatively a new networking concept that could provide a robust communication in wide range of implementations from the space to battlefield or other military usage. However in such dynamic networks, which could be considered as a set of intermittently connected nodes, message forwarding strategy is a key issue. Existing routing solutions concentrate mainly on two major routing families flooding and knowledge based algorithms. This paper presents SocialRouting - the social-based routing algorithm designed for DTN. The use of the social properties of wireless mobile nodes is the novel way of message routing that is based on message ferrying between separated parts of the network. Proposed idea has been extensively tested using simulation tools. The simulations were made based on especially designed for measurements in DTN scenarios and compared with popular solutions.
EN
At this moment there is a lack of research respecting Mobile Ad-hoc Networks (MANET) address assignment methods used in Delay Tolerant Networks (DTN). The goal of this paper is to review the SDAD, WDAD and Buddy methods of IP address assignment known from MANET in difficult environment of Delay and Disruptive Tolerant Networks. Our research allows us for estimating the effectiveness of the chosen solution and, therefore, to choose the most suitable one for specified conditions. As a part of the work we have created a tool which allows to compare these methods in terms of capability of solving address conflicts and network load. Our simulator was created from scratch in Java programming language in such a manner, that implementation of new features and improvements in the future will be as convenient as possible.
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