1,111 research outputs found
On Energy Efficiency and Delay Minimization in Reactive Protocols in Wireless Multi-hop Networks
In Wireless Multi-hop Networks (WMhNs), routing protocols with energy
efficient and delay reduction techniques are needed to fulfill users demands.
In this paper, we present Linear Programming models (LP_models) to assess and
enhance reactive routing protocols. To practically examine constraints of
respective LP_models over reactive protocols, we select AODV, DSR and DYMO. It
is deduced from analytical simulations of LP_models in MATLAB that quick route
repair reduces routing latency and optimizations of retransmission attempts
results efficient energy utilization. To provide quick repair, we enhance AODV
and DSR. To practically examine the efficiency of enhanced protocols in
different scenarios of WMhNs, we conduct simulations using NS- 2. From
simulation results, enhanced DSR and AODV achieve efficient output by
optimizing routing latencies and routing load in terms of retransmission
attempts
Identifying Design Requirements for Wireless Routing Link Metrics
In this paper, we identify and analyze the requirements to design a new
routing link metric for wireless multihop networks. Considering these
requirements, when a link metric is proposed, then both the design and
implementation of the link metric with a routing protocol become easy.
Secondly, the underlying network issues can easily be tackled. Thirdly, an
appreciable performance of the network is guaranteed. Along with the existing
implementation of three link metrics Expected Transmission Count (ETX), Minimum
Delay (MD), and Minimum Loss (ML), we implement inverse ETX; invETX with
Optimized Link State Routing (OLSR) using NS-2.34. The simulation results show
that how the computational burden of a metric degrades the performance of the
respective protocol and how a metric has to trade-off between different
performance parameters
From carbon nanotubes and silicate layers to graphene platelets for polymer nanocomposites
In spite of extensive studies conducted on carbon nanotubes and silicate layers for their polymer-based nanocomposites, the rise of graphene now provides a more promising candidate due to its exceptionally high mechanical performance and electrical and thermal conductivities. The present study developed a facile approach to fabricate epoxy–graphene nanocomposites by thermally expanding a commercial product followed by ultrasonication and solution-compounding with epoxy, and investigated their morphologies, mechanical properties, electrical conductivity and thermal mechanical behaviour. Graphene platelets (GnPs) of 3.5
SIMPLE: Stable Increased-throughput Multi-hop Protocol for Link Efficiency in Wireless Body Area Networks
In this work, we propose a reliable, power efficient and high throughput
routing protocol for Wireless Body Area Networks (WBANs). We use multi-hop
topology to achieve minimum energy consumption and longer network lifetime. We
propose a cost function to select parent node or forwarder. Proposed cost
function selects a parent node which has high residual energy and minimum
distance to sink. Residual energy parameter balances the energy consumption
among the sensor nodes while distance parameter ensures successful packet
delivery to sink. Simulation results show that our proposed protocol maximize
the network stability period and nodes stay alive for longer period. Longer
stability period contributes high packet delivery to sink which is major
interest for continuous patient monitoring.Comment: IEEE 8th International Conference on Broadband and Wireless
Computing, Communication and Applications (BWCCA'13), Compiegne, Franc
An energy-aware and QOS assured wireless multi-hop transmission protocol
A thesis submitted in fulfillment of the requirements for the degree of Master of Science by researchThe Ad-hoc network is set up with multiple wireless devices without any pre-existing infrastructure. It usually supports best-effort traffic and occasionally some kinds of Quality of Service (QoS). However, there are some applications with real-time traffic requirements where deadlines must be met. To meet deadlines, the communication network has to support the timely delivery of inter-task messages. Furthermore, energy efficiency is a critical issue for battery-powered mobile devices in ad-hoc networks. Thus, A QoS guaranteed and energy-aware transmission scheme is one hot of research topics in the research area.
The MSc research work is based on the idea of Real-Time Wireless Multi-hop Protocol (RT-WMP). RT-WMP is a well known protocol originally used in the robots control area. It allows wireless real-time traffic in relatively small mobile ad-hoc networks using the low-cost commercial IEEE 802.11 technology. The proposed scheme is based on a token-passing approach and message exchange is priority based.
The idea of energy-aware routing mechanism is based on the AODV protocol. This energy-saving mechanism is analysed and simulated in our study as an extension of the RT-WMP.
From the simulation results and analysis, it has been shown that adding energy-aware mechanism to RT-WMP is meaningful to optimise the performance of traffic on the network
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
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