1,220 research outputs found
Quality Of Service Enabled Cross-Layer Multicast Framework For Mobile Ad Hoc Networks.
Rangkaian ad hoc bergerak merupakan suatu rangkaian tanpa wayar yang boleh dibentuk secara bebas, dinamik serta disusunatur dan ditadbir dalam bentuk topologi rangkaian sementara dan arbitrari.
Mobile ad hoc networks (MANETs) are wireless networks that can freely and dynamically be created, organized and administered into arbitrary and temporary network topologies
Review of multicast QoS routing protocols for mobile ad hoc networks
A Mobile Ad hoc NETwork (MANET) is consisting of a
collection of wireless mobile nodes, which form a temporary
network without relying on any existing infrastructure or
centralized administration. Since the bandwidth of MANETs is
limited and shared between the participating nodes in the
network, it is important to efficiently utilize the network
bandwidth. Multicasting can minimize the link bandwidth
consumption and reduce the communication cost by sending the
same data to multiple participants. Multicast service is critical for
applications that need collaboration of team of users.
Multicasting in MANETs becomes a hot research area due to the
increasing popularity of group communication applications such
as video conferencing and interactive television. Recently,
multimedia and group-oriented computing gains more popularity
for users of ad hoc networks. So, effective Quality of Service
(QoS) multicasting protocol plays significant role in MANETs.
In this paper, we are presenting an overview of set of the most
recent QoS multicast routing protocols that have been proposed
in order to provide the researchers with a clear view of what has
been done in this field
Network emulation focusing on QoS-Oriented satellite communication
This chapter proposes network emulation basics and a complete case study of QoS-oriented Satellite Communication
Experimental evaluation of the usage of ad hoc networks as stubs for multiservice networks
This paper describes an experimental evaluation of a multiservice ad hoc network, aimed to be interconnected with an infrastructure, operator-managed network. This network supports the efficient delivery of services, unicast and multicast, legacy and multimedia, to users connected in the ad hoc network. It contains the following functionalities: routing and delivery of unicast and multicast services; distributed QoS mechanisms to support service differentiation and resource control responsive to node mobility; security, charging, and rewarding mechanisms to ensure the correct behaviour of the users in the ad hoc network. This paper experimentally evaluates the performance of multiple mechanisms, and the influence and performance penalty introduced in the network, with the incremental inclusion of new functionalities. The performance results obtained in the different real scenarios may question the real usage of ad-hoc networks for more than a minimal number of hops with such a large number of functionalities deployed
Na neizrazitoj logici zasnovano upravljanje frekvencijom za ODMRP u mobilnim ad hoc mrežama
On Demand Multicast Routing Protocol (ODMRP) is a popular solution designed for ad hoc networks with mobile hosts. Its efficiency, simplicity, and robustness to mobility render it one of the most widely used multicast routing protocols in Mobile Ad hoc NETworks (MANET). In ODMRP, there is no input rate control for upper layer traffic. So, it’s possible that high dense traffic flow causes congestion in networks. In this work, an enhancement to ODMRP is proposed referred to as fuzzy logic based Rate Control ODMRP (FRC-ODMRP). FRC-ODMRP attempts to adapt the arrival rate from upper layers to the state in the network by using feedback information from receivers of the multicast group. Accordingly, source comes up with a decision whether to increase or decrease its transmission rate based on information collected from the receivers. In this research, delay and packet delivery ratio reconsidered as indicators of congestion in addition to number of received packets. Simulation results demonstrate that FRC-ODMRP achieves significant performance improvements in comparison to conventional ODMRP and QoS-ODMRP. Indeed, it efficiently handles simultaneous traffic flows such that no one could dominate available bandwidth of networks.On Demand Multicast Routing Protocol (ODMRP) popularno je rješenje namijenjeno ad hoc mrežama s mobilnim domaćinima. Efikasnost, jednostavnost i robusnost u smislu mobilnosti učini su ovu metodu jednom od najraširenijih multicast protokola u ad hoc mobilnim mrežam (eng. MANET). Kod ODMRP-a nema upravljanja ulaznom frekvencijom za promet višeg sloja. Zbog toga je moguće da gusti promet uzrokuje zagušenje u mrežama. U ovome je radu predstavljeno poboljšanje ODMRP-a nazvano ODMRP zasnovan na fuzzy logici (FRC-ODRMP). FRC-ODRMP pokušava prilagoditi dolazne signale iz viših slojeva stanju u mreži koristeći povratnu informaciju od primatelja iz multicast grupe. Prilikom istraživanja dodatno je uzet omjer kašnjenja i dostavljenih paketa kao pokazatelj zagušenosti mreže uz broj dostavljenih paketa. Simulacijski rezultati pokazuju kako FRC-ODMRP značajno poboljšava performanse u odnosu na konvencionalni ODMRP i Qos-ODMRP. Dodatno, simultani promet efikasno je upravljan tako da nitko ne može dominirati dostupnom propusnošću mreže
Research on Quality of Service Based Routing Protocols for Mobile Ad Hoc Networks
Quality of service (QoS) based routing protocols play a significant role in MANETs to maintain proper flow of data with efficient power consumption and without data loss. However, several network resource based technical challenges or issues are encountered in the design and implementation of QoS routing protocols that perform their routing function by considering the shortest route or the lowest cost. Furthermore, a secondary route is not reserved and alternative routes are not searched unless the established route is broken. The current structures of the state-of-the-art protocols for MANETs are not appropriate for today's high bandwidth and mobility requirements. Therefore, research on new routing protocols is needed, considering energy level, coverage, location, speed, movement, and link stability instead of only shortest path and lowest cost. This paper summarizes the main characteristics of QoS-based routing protocols to facilitate researchers to design and select QoS-based routing protocols. In this study, a wide range of protocols with their characteristics were classified according to QoS routing strategy, routing information update mechanism, interaction between network and MAC layer, QoS constraints, QoS guarantee type and number of discovered routes. In addition, the protocols were compared in terms of properties, design features, challenges and QoS metrics
Security and Privacy Issues in Wireless Mesh Networks: A Survey
This book chapter identifies various security threats in wireless mesh
network (WMN). Keeping in mind the critical requirement of security and user
privacy in WMNs, this chapter provides a comprehensive overview of various
possible attacks on different layers of the communication protocol stack for
WMNs and their corresponding defense mechanisms. First, it identifies the
security vulnerabilities in the physical, link, network, transport, application
layers. Furthermore, various possible attacks on the key management protocols,
user authentication and access control protocols, and user privacy preservation
protocols are presented. After enumerating various possible attacks, the
chapter provides a detailed discussion on various existing security mechanisms
and protocols to defend against and wherever possible prevent the possible
attacks. Comparative analyses are also presented on the security schemes with
regards to the cryptographic schemes used, key management strategies deployed,
use of any trusted third party, computation and communication overhead involved
etc. The chapter then presents a brief discussion on various trust management
approaches for WMNs since trust and reputation-based schemes are increasingly
becoming popular for enforcing security in wireless networks. A number of open
problems in security and privacy issues for WMNs are subsequently discussed
before the chapter is finally concluded.Comment: 62 pages, 12 figures, 6 tables. This chapter is an extension of the
author's previous submission in arXiv submission: arXiv:1102.1226. There are
some text overlaps with the previous submissio
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