4,479 research outputs found
Ad hoc network security and modeling with stochastic petri nets
Advances in wireless technology and portable computing along with demands for high user mobility have provided a major promotion toward the development of ad hoc networks. These networks feature dynamic topology, self-organization, limited bandwidth and battery power of a node. Unlike the existing commercial wireless systems and fixed infrastructure networks, they do not rely on specialized routers for path discovery and traffic routing. Security is an important issue in such networks. Typically, mobile nodes are significantly more susceptible to physical attacks than their wired counterparts.
This research intends to investigate the ad hoc network routing security by proposing a performance enhanced Secure ad hoc On-demand Routing protocol (SOR). Specifically, it presents a method to embed Security Level into ad hoc on-demand routing protocols using node-disjoint multipath, and to use maximum hopcount to restrict the number of routing packets in a specific area. The proposed scheme enables the use of security as a marked factor to improve the relevance of the routes discovered by ad hoc routing protocols. It provides customizable security to the flow of routing protocol messages. In general, SOR offers an alternative way to implement security in on-demand routing protocols.
Ad hoc network is too complex to allow analytical study for explicit performance expressions. This research presents a Stochastic Petri net-based approach to modeling and analysis of mobile ad hoc network. This work illustrates how this model is built as a scalable model and used to exploit the characteristics of the networks. The proposed scheme is a powerful analytical model that can be used to derive network performance much more easily than a simulation-based approach. Furthermore, the proposed model is extended to study the performance of ad hoc network security by adding multipath selection and security measurement parameters. This research gives a quantificational measurement to analyze the performance of a modified SPN model under the effect of multipath and attack of a hypothetical compromised node
Multipath optimized link state routing for mobile ad hoc networks
International audienceMultipath routing protocols for Mobile Ad hoc NETwork (MANET) address the problem of scalability, security (confidentiality and integrity), lifetime of networks, instability of wireless transmissions, and their adaptation to applications. Our protocol, called MP-OLSR (MultiPath OLSR), is a multipath routing protocol based on OLSR. The Multipath Dijkstra Algorithm is proposed to obtain multiple paths. The algorithm gains great flexibility and extensibility by employing different link metrics and cost functions. In addition, route recovery and loop detection are implemented in MP-OLSR in order to improve quality of service regarding OLSR. The backward compatibility with OLSR based on IP source routing is also studied. Simulation based on Qualnet simulator is performed in different scenarios. A testbed is also set up to validate the protocol in real world. The results reveal that MP-OLSR is suitable for mobile, large and dense networks with large traffic, and could satisfy critical multimedia applications with high on time constraints
Simulation and Performance Analysis of MP-OLSR for Mobile Ad hoc Networks
Mobile ad hoc networks (MANETs) consist of a collection of wireless mobile
nodes which dynamically exchange data without reliance on a fixed base station
or a wired backbone network, which makes routing a crucial issue for the design
of a ad hoc networks. In this paper we discussed a hybrid multipath routing
protocol named MP-OLSR. It is based on the link state algorithm and employs
periodic exchange of messages to maintain topology information of the networks.
In the mean time, it updates the routing table in an on-demand scheme and
forwards the packets in multiple paths which have been determined at the
source. If a link failure is detected, the algorithm recovers the route
automatically. Concerning the instability of the wireless networks, the
redundancy coding is used to improve the delivery ratio. The simulation in NS2
shows that the new protocol can effectively improve the performance of the
networks
An enhanced Multipath Strategy in Mobile Ad hoc Routing Protocols
The various routing protocols in Mobile Ad hoc Networks follow different
strategies to send the information from one node to another. The nodes in the
network are non static and they move randomly and are prone to link failure
which makes always to find new routes to the destination. This research mainly
focused on the study of the characteristics of multipath routing protocols in
MANETS. Two of the multipath routing protocols were investigated and a
comparative study along with simulation using NS2 was done between DSR and AODV
to propose an enhanced approach to reach the destination maintaining the QoS. A
possible optimization to the DSR and AODV routing protocols was proposed to
make no node to be overburdened by distributing the load after finding the
alternate multipath routes which were discovered in the Route discovery
process. The simulation shows that the differences in the protocol highlighted
major differences with the protocol performance. These differences have been
analyzed with various network size, mobility, and network load. A new search
table named Search of Next Node Enquiry Table (SONNET) was proposed to find the
best neighbor node. Using SONNET the node selects the neighbor which can be
reached in less number of hops and with less time delay and maintaining the
QoS
Improving Energy Efficiency in MANETs by Multi-Path Routing
Some multi-path routing algorithm in MANET, simultaneously send information
to the destination through several directions to reduce end-to-end delay. In
all these algorithms, the sent traffic through a path affects the adjacent path
and unintentionally increases the delay due to the use of adjacent paths.
Because, there are repetitive competitions among neighboring nodes, in order to
obtain the joint channel in adjacent paths. The represented algorithm in this
study tries to discover the distinct paths between source and destination nodes
with using Omni directional antennas, to send information through these
simultaneously. For this purpose, the number of active neighbors is counted in
each direction with using a strategy. These criterions are effectively used to
select routes. Proposed algorithm is based on AODV routing algorithm, and in
the end it is compared with AOMDV, AODVM, and IZM-DSR algorithms which are
multi-path routing algorithms based on AODV and DSR. Simulation results show
that using the proposed algorithm creates a significant improvement in energy
efficiency and reducing end-to-end delay
Flow Allocation for Maximum Throughput and Bounded Delay on Multiple Disjoint Paths for Random Access Wireless Multihop Networks
In this paper, we consider random access, wireless, multi-hop networks, with
multi-packet reception capabilities, where multiple flows are forwarded to the
gateways through node disjoint paths. We explore the issue of allocating flow
on multiple paths, exhibiting both intra- and inter-path interference, in order
to maximize average aggregate flow throughput (AAT) and also provide bounded
packet delay. A distributed flow allocation scheme is proposed where allocation
of flow on paths is formulated as an optimization problem. Through an
illustrative topology it is shown that the corresponding problem is non-convex.
Furthermore, a simple, but accurate model is employed for the average aggregate
throughput achieved by all flows, that captures both intra- and inter-path
interference through the SINR model. The proposed scheme is evaluated through
Ns2 simulations of several random wireless scenarios. Simulation results reveal
that, the model employed, accurately captures the AAT observed in the simulated
scenarios, even when the assumption of saturated queues is removed. Simulation
results also show that the proposed scheme achieves significantly higher AAT,
for the vast majority of the wireless scenarios explored, than the following
flow allocation schemes: one that assigns flows on paths on a round-robin
fashion, one that optimally utilizes the best path only, and another one that
assigns the maximum possible flow on each path. Finally, a variant of the
proposed scheme is explored, where interference for each link is approximated
by considering its dominant interfering nodes only.Comment: IEEE Transactions on Vehicular Technolog
Energy Efficient Clustering and Routing in Mobile Wireless Sensor Network
A critical need in Mobile Wireless Sensor Network (MWSN) is to achieve energy
efficiency during routing as the sensor nodes have scarce energy resource. The
nodes' mobility in MWSN poses a challenge to design an energy efficient routing
protocol. Clustering helps to achieve energy efficiency by reducing the
organization complexity overhead of the network which is proportional to the
number of nodes in the network. This paper proposes a novel hybrid multipath
routing algorithm with an efficient clustering technique. A node is selected as
cluster head if it has high surplus energy, better transmission range and least
mobility. The Energy Aware (EA) selection mechanism and the Maximal Nodal
Surplus Energy estimation technique incorporated in this algorithm improves the
energy performance during routing. Simulation results can show that the
proposed clustering and routing algorithm can scale well in dynamic and energy
deficient mobile sensor network.Comment: 9 pages, 4 figure
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