1,182 research outputs found
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
Enhancement of Network Life Time using Binary Tree Based Multicast Routing Protocol for Mobile Ad hoc Network
A mobile ad hoc network (MANET) is an interconnected system of mobile hosts without a fixed infrastructure. In MANETs, each mobile host has multi-hop transmission capability, and it has to serve as a router. Owing to the dynamic topology and limited resources of mobile hosts, the routing scheme in MANETs presents an important challenge. In this study, a Enhancement of Network Life Time using Binary Tree Based Multicast Routing Protocol for MANET is proposed. In this proposed scheme, all nodes are randomly classified into two types, group-1 and group-2. To achieve the load balance, two multicast trees (tree-1 for group-1 and tree-2 for group-2) are constructed. The proposed system mainly focused on maintaining route stability. Thus proposed system outperform AOMDV version of AODV in term of Performance evaluation metrics such as packet delivery ratio, control overhead , Network life time, Normalized delay
Routing in mobile Ad Hoc Networks
A Mobile Ad Hoc Network (MANET) is built on the fly where a number of wireless mobile nodes work in cooperation without the engagement of any centralized access point or any fixed infrastructure. Two nodes in such a network can communicate in a bidirectional manner if and only if the distance between them is at most the minimum of their transmission ranges. When a node wants to communicate with a node outside its transmission range, a multihop routing strategy is used which involves some intermediate nodes. Because
of the movements of nodes, there is a constant possibility of topology change in MANET. Considering this unique aspect of MANET, a number of routing protocols have been proposed so far. This chapter gives an overview of the past, current, and future research areas for routing in MANET. In this chapter we will learn about the following things:
- The preliminaries of mobile ad hoc network
- The challenges for routing in MANET
- Expected properties of a MANET routing protocol
- Categories of routing protocols for MANET
- Major routing protocols for MANET
- Criteria for performance comparison of the routing protocols for MANET
- Achievements and future research directions
- Expectations and realit
Requirement analysis for building practical accident warning systems based on vehicular ad-hoc networks
An Accident Warning System (AWS) is a safety application that provides collision avoidance notifications for next generation vehicles whilst Vehicular Ad-hoc Networks (VANETs) provide the communication functionality to exchange these notifi- cations. Despite much previous research, there is little agreement on the requirements for accident warning systems. In order to build a practical warning system, it is important to ascertain the system requirements, information to be exchanged, and protocols needed for communication between vehicles. This paper presents a practical model of an accident warning system by stipulating the requirements in a realistic manner and thoroughly reviewing previous proposals with a view to identify gaps in this area
Xcast Based Routing Protocol For Push To Talk Application In Mobile Ad Hoc Networks
Mobile ad-hoc networks comprise a type of wireless network that can be easily
created without the need for network infrastructure or administration. These
networks are organized and administered into temporary and dynamic network
topologies. Unfortunately, mobile ad-hoc networks suffer from some limitations
related to insufficient bandwidth. The proliferation of new IP Multimedia subsystem
services (IMs), such as Push-to-talk (PTT) applications consume large amounts of
bandwidth, resulting in degraded QoS performance of mobile ad-hoc networks. In
this thesis, a Priority XCAST based routing protocol (P-XCAST) is proposed for
mobile ad-hoc networks to minimize bandwidth consumption. P-XCAST is based on
demand route requests and route reply mechanisms for every destination in the PXCAST
layer. To build the network topology and fill up the route table for nodes,
the information in the route table is used to classify the XCAST list of destinations
according to similarities on their next hop. Furthermore, P-XCAST is merged with a
proposed Group Management algorithm to handle node mobility by classifying nodes
into two types: group head and member. The proposed protocol was tested using the
GloMoSim network simulator under different network scenarios to investigate
Quality of Service (QoS) performance network metrics. P-XCAST performance was
better by about 20% than those of other tested routing protocols by supporting of
group size up to twenty receivers with an acceptable QoS. Therefore, it can be
applied under different network scenarios (static or dynamic). In addition Link
throughput and average delay was calculated using queuing network model; as this
model is suitable for evaluating the IEEE 802.11 MAC that is used for push to talk applications. The analytical results for link throughput and average delay were used
to validate the simulated results
USING NS-2 COMPARISON OF GEOGRAPHICAL AND TOPOLOGICAL MULTICAST ROUTING PROTOCOLS ON WIRELESS AD HOC NETWORKS
Performance evaluation of geographical and topological multicast routing algorithms for cellular Wi-Fi ad-hoc networks is offered. Flooding and On-call for Multicast Routing Protocol (ODMRP) are simulated and in comparison with novels protocols: Topological Multicast Routing (ToMuRo) and Geographical Multicast Routing (GeMuRo) in pedestrian and vehicular situations. The situations evaluated recollect one multicast transmitter and one, two and three multicast receivers under numerous mobility and transmission levels. The conduct of 150 nodes is evaluated in terms of cease to end postpone (EED), jitter, packet delivery ratio, and overhead. Consequences display that ToMuRo is suitable for pedestrian eventualities because of its tree-based structure and GeMuRo is right for vehicular situations because its miles based on a mesh topology
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
Secure Routing in Wireless Mesh Networks
Wireless mesh networks (WMNs) have emerged as a promising concept to meet the
challenges in next-generation networks such as providing flexible, adaptive,
and reconfigurable architecture while offering cost-effective solutions to the
service providers. Unlike traditional Wi-Fi networks, with each access point
(AP) connected to the wired network, in WMNs only a subset of the APs are
required to be connected to the wired network. The APs that are connected to
the wired network are called the Internet gateways (IGWs), while the APs that
do not have wired connections are called the mesh routers (MRs). The MRs are
connected to the IGWs using multi-hop communication. The IGWs provide access to
conventional clients and interconnect ad hoc, sensor, cellular, and other
networks to the Internet. However, most of the existing routing protocols for
WMNs are extensions of protocols originally designed for mobile ad hoc networks
(MANETs) and thus they perform sub-optimally. Moreover, most routing protocols
for WMNs are designed without security issues in mind, where the nodes are all
assumed to be honest. In practical deployment scenarios, this assumption does
not hold. This chapter provides a comprehensive overview of security issues in
WMNs and then particularly focuses on secure routing in these networks. First,
it identifies security vulnerabilities in the medium access control (MAC) and
the network layers. Various possibilities of compromising data confidentiality,
data integrity, replay attacks and offline cryptanalysis are also discussed.
Then various types of attacks in the MAC and the network layers are discussed.
After enumerating the various types of attacks on the MAC and the network
layer, the chapter briefly discusses on some of the preventive mechanisms for
these attacks.Comment: 44 pages, 17 figures, 5 table
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