Ns-2 Research Papers - Academia.edu (original) (raw)

Top Papers
Most Cited Papers
Most Downloaded Papers
Newest Papers
People
- by
- •
- MANET Routing protocols, Performance Evaluation, Wireless Mobile Charger, Manet

E-health Monitoring Systems (EHMS) have become very
important part of our life in recent years. The development of mobile phones and other handheld devices have given the ability to EHMS for using different types of networks. The EHMS consists of many services like emergency services. During emergency situations, the communication may suffer congestion, delay, and data loss. One key challenge for EHMS is determining the suitable routing protocol to ensure that data have been transmitted from one node to the other as quickly as possible.
This thesis aims to determine the best routing protocol for EHMS
and design an intelligent system for e-healthcare to support emergency cases for people living with chronic diseases such as blood pressure and diabetes.
In this thesis, we will present a performance comparison between
DSDV and AODV routing protocols in two scenarios based on varying number of nodes, node speed and pause time by using NS-2 simulator in LINUX environment. The performance of these two routing protocols is analyzed with average end to end delay, packet delivery ratio, and normalized routing load metrics.
In addition, this thesis introduces the proposed architecture of an
Intelligent E-health Monitoring System (IEHMS). IEHMS is a web based application that has been designed using PHP and MYSQL to provide automatically vital sign monitoring for patients, tracking, data integration, and communications between different sites (hospitals, ambulances, and doctors).
By our experimental results, we concluded that DSDV has better
performance than AODV for EHMS where DSDV has less routing load when nodes have high mobility and produces low average end-to-end delay as compared to AODV. We also concluded that IEHMS is efficient system because it gives the capability for medical staff to check the patient's records history, avoid potential errors and complications, cost and time saving by allowing care closer to home, and locate the patient and sending help to him immediately by using GPS system.

- by Mohammed Najm Abdullah Al Salam
- •
- Ns-2, DSDV, E-health Monitoring Systems
- by Cmanikandan Cmanikandan
- •
- Computer Science, Network Security, Computer Networks, Security
- by Fazlullah Khan
- •
- Wireless Communications, Computer Networks, Routing protocols, Manet
- by Amry Daulat Gultom
- •
- Wireless Communications, UMTS, QoS, 3G
- by Mitko Shopov and +2
- •
- Distributed Embedded Systems, Ns-2

In layered networks, reliability is a major concern as link failures at lower layer will have a great impact on network reliability. Failure at a lower layer may lead to multiple failures at the upper layers which deteriorate the network performance. In this paper, the scenario of such a layered wireless sensor network is considered for Ad hoc On-Demand Distance Vector (AODV) and Multi Commodity Flow (MCF) routing protocols. MCF is developed using polynomial time approximation algorithms for the failure polynomial. Both protocols are compared in terms of different network parameters such as throughput, packet loss and end to end delay. It was shown that the network reliability is better when MCF protocol is used. It was also shown that maximizing the min cut of the layered network maximizes reliability in the terms of successful packet transmission of network. Thetwo routing protocolsare implemented in the scenario of discrete network event simulator NS-2.

- by Mohamed El-sharkawy and +1
- •
- AODV, Ns-2, Mcf

Voice over Internet Protocol (VoIP) may provide good services through Vehicular ad hoc networks
(VANETs) platform by providing services to many application scenarios range from safety to comfort.
However, VANETs networks introduce many challenges for supporting voice with QoS requirements. In
this paper, our study is based on Inter-Vehicle voice streaming rely on multi-hop fashion. For this task, a
performance evaluation of various audio CODECs will be analyzed by mean of simulations.
Furthermore, we test the impact of network environment on QoS metrics. To achieve good results,
CODECs behaviour is tested by using mobility information obtained from vehicular traffic generator. The
mobility model is based on the real road maps of an urban environment. Focusing on inter-vehicular
voice traffic quality, we provide simulations results in terms of both user level (MOS) metrics and
network level (such as Losses). According to this performance evaluation, we show that G.723.1 CODEC
worked well in the urban VANET environment.

- by IOSR Journals
- •
- Wireless Communications, Network Security, Survey, Manet

In this paper we discuss various approaches to simulating real-time Internet-based teleoperation systems. Focus is on simulation of the communication link, which is a critical component in teleoperation systems. Some of the objectives of simulations are to compare the performance of operators in fixed network conditions and to compare the performance of an
operator over varying network conditions. To accomplish these
goals, NS-2 is used with modified classes to model teleoperation
systems. Two methods for simulation are co-simulation, where
the system dynamics and the network are simulated at the same
time, and sequential simulation, where the network and system
dynamics are simulated in separate steps. The differences in
accuracy and implementation are compared by an illustrative
experiment. This paper also investigates methods for interactive
simulations, which receive command inputs from an external
master device controlled by a human operator. The real-time
scheduler and network emulation are NS-2 addons that enable
interactive simulations. Since computation time is an important
limitation for simulations, a sequential simulation approach can
be used for large-scale networks.

- by Wai-keung Fung
- •
- Teleoperation, Network Simulation, Ns-2

A new Medium Access Control (MAC) has been simulated and added to Net- work Simulator, version 2.31. The new MAC layer uses the slotted physical medium. This document explains the simulation and the procedure of instal- lation of the... more

- by annie gravey
- •
- Simulation, Ns-2, MAC, Optical Packet Switching

handover performance plays a crucial role in ensuring the quality of real-time applications in WiMAX networks. In general, the total delay associated with the handover process can be divided into three category: i) link layer handover delay , ii) IP layer handover delay, iii) Security sub-layer handover delay , research shows that a large portion of the delay related to handover are actually comes from user authentication and network entry and re-entry , real-time applications such as VoIP and video streaming .require a minimum interruption for a suitable service , sadly the existing design of the handover scheme could not provide seamless safe connection , therefore the use of such application will be unlikely , in this paper we introduce an efficient design that can provide fast and secure communication especially over the subsequent handover , we named it FSSHO for short , in our proposal we consider the use the of a pre-authentication scheme and prior backhaul inter-communication , our design generate a minimum delay that is more than suitable for real-time application. From our analytical comparison and simulation result we can see that our FSSHO approach achieves 72% improve over the standard and 38% improve over the enhanced scheme in [1]

The Transmission Control Protocol (TCP) is the dominating end-to-end protocol on the
internet today but still it faces congestion problems in some cases. To overcome congestion
problems, several congestion control and avoiding mechanisms namely: Tahoe, Reno, Vegas, and
Sack etc. all with different features and advantages but with maximal throughput as main objective,
which are termed as the clones of TCP, have been incorporated into TCP/IP protocol for handling
congestion efficiently in different network scenarios. However, one clone cannot be suitable for each
case. So this paper has investigated the characteristics of the mentioned clones and calculated
throughputs of them in simulated environment varying various performances metrics such as delay,
buffer size, error rate, number of traffic and bandwidth for finding which one is the best for what
scenario.

- by Md. Anwar Hossain
- •
- Ns-2

—Sequence-based schemes determine beacon sequence to help sensor node localization. Due to the ambiguity of RSS over distance, sequence-based scheme may have RSS-inconsistency problem, i.e., no location in the localization space could match the beacon sequence. Besides, determining the matched location is costly. In this paper, we introduce a RSS-inconsistency avoidance localization scheme, which takes linear-time. Our scheme is applicable to real sensors. Our localization error in real sensors is less than 0.34×communication radius. According to the simulation results in NS-2, our scheme is more accurate and reliable than existing schemes.

Wireless networks are gaining popularity to its peak today, as the users want wireless connectivity irrespective of their geographic position. There is an increasing threat of attacks on the Mobile Ad-hoc Networks (MANET). Vampire attack is one of the security threat in which the traffic is redirected to such a node that actually does not exist in the network. It's an analogy to the Vampire in the universe in which things disappear. The node presents itself in such a way to the node that it can attack other nodes and networks knowing that it has the shortest path. MANETs must have a secure way for transmission and communication which is quite challenging and vital issue. In order to provide secure communication and transmission, researcher worked specifically on the security issues in MANETs, and many secure routing protocols and security measures within the networks were proposed. Previously the works done on security issues in MANET were based on reactive routing protocol like dynamic source routing (DSR). Different kinds of attacks were studied, and their effects were elaborated by stating how these attacks disrupt the performance of MANET. The general purpose of this project is to study the effects of Vampire attack in MANET using Reactive routing protocol Ad-Hoc on Demand Distance Vector (AODV). Comparative analysis of Vampire attack for both protocols is taken into account. The impact of Vampire attack on the performance of MANET is evaluated finding out which protocol is more vulnerable to the attack and how much is the impact of the attack on both protocols. The measurements were taken in the light of throughput, end-to-end delay and network load. Simulation is done in Network Simulator. (NS-2).

In wireless sensor networks, sensor nodes fail either when s
ome critical event occurs at the node or when
the battery of the nodes is completely drained. If the remaini
ng nodes in the sensor network are not aware
of the node failure, the network might under undergo significant
broadcast delay and path loss. An alarm
packet has to be broadcast throughout the network when any critical
event occurs and the transmission
path must be recovered to achieve better quality of service
in the sensor network. This paper utilizes least
disruptive topology repair (LeDir) algorithm to minimize the p
ower consumption and to handle such
critical events. LeDir algorithm is used to recover the tr
ansmission path and to ensure that the quality of
service issues in the network is met. The variations in
the throughput, roundtrip time, broadcast delays and
packet delivery ratio of the network are observed by pe
rforming multiple NS-2 simulations. It is observed
that the throughput of the network could be quickly regained when
the transmission path is recovered by
node replacement.

- by Atul Vaibhav
- •
- Wireless Communications, Computer Networks, Wlan, Ns-2
- by Yuvaraj Beegala
- •
- MANET Routing protocols, Wireless Mobile Charger, DSR, AODV

The Efficient routing protocols can provide significant benefits to mobile ad hoc networks, in terms of both performance and reliability. Many routing protocols for such networks have been proposed so far. Amongst the most popular ones are Ad hoc On-demand Distance Vector (AODV), Destination-Sequenced Distance-Vector Routing protocol (DSDV), Dynamic Source Routing Protocol (DSR), and Optimum Link State Routing (OLSR). Despite the popularity of those protocols, research efforts have not focused much in evaluating their performance when applied to variable bit rate (VBR). In this paper we present our observations regarding the performance comparison of the above protocols for VBR in mobile ad hoc networks (MANETs). We perform extensive simulations, using NS-2 simulator. Our studies have shown that reactive protocols perform better than proactive protocols. Further DSR has performed well for the performance parameters namely delivery ratio and routing overload while AODV performed better in terms of average delay.

- by Lokanatha Reddy
- •
- MANET Routing protocols, Wireless Mobile Charger, DSR, AODV

In this paper, we will focus on the performance evaluation of a vehicular mobility scenario graph. Indeed, we will analyze the performance metrics (throughput, packets loss and end to end delay) using the IEEE 802.11p standard of the proposed mobility graph. In addition, we examine the impact of the packet length, vehicle speed and routing protocols (Ad-Hoc On-demand Distance Vector " AODV " , Destination Sequenced Distance Vector " DSDV " and DumbAgent). Our simulations are based on the networks simulator " NS-2 " and the mobility simulator " VanetMobisim " to evaluate the performance of the vehicular ad hoc network.

Data mining is important process to extract the useful information and pattern from huge amount of data. NS-2 is an efficient tool to build the environment of network. The results from simulate these environment in NS-2 is trace file that contains several columns and lines represent the network events. This trace file can be used to analyse the network according to performance metrics but it has redundant columns and rows. So, this paper is to perform the data mining in order to find only the necessary information in analysis operation to reduce the execution time and the storage size of the trace file.

- by Yuvaraj Beegala
- •
- MANET Routing protocols, Wireless Mobile Charger, DSR, AODV

With the growing trend of wireless technologies and the great need of being
always on (line) and anywhere culminate with the development of a new
standard the IEEE802.21, bythe IEEE group. This standard is designed to
streamline the handoversbetween different technologies through normalized
mechanisms and events, with the purpose of making the different technologies
seamless to the upper-layers
This thesis presents mobility mechanisms independent of the wireless
technologies at this stage, particularly WiMAX technology with support for
mobility and the WiFi technology. It is described how are processed
heterogeneous handovers based on IEEE802.16 standard and the IEEE802.21
and are purposed some changes on it.
It is then analyzed the network simulator, which was used to assess the
performance of the handovers in heterogeneous networks through the new
mechanisms established and purposed, and changes are made to support the
signalling and features specified.
On this Thesis are simulated several scenarios with handovers of intra-technology and inter-technology in order to obtain performance parameters.
The obtained results with the changes produced in the simulator show that this
new standard and the purposed mechanism of integration with the technologies
802.11 and 802.16, bring significant improvements on the time of handovers as
well as on the support of QoS.

- by Márcio Melo
- •
- Mobility, Wimax, Ns-2, Inter Handover

One of the main problems in video transmission is the bandwidth fluctuation in wireless channel. Therefore, there is an urgent need to find an efficient bandwidth utilization and method. This research utilizes the Combined Scalable Video Coding (CSVC) which comes from Joint Scalable Video Model (JSVM). In the combined scalable video coding, we implement Coarse Grain Scalability (CGS) and Medium Grain Scalability (MGS). We propose a new scheme in which it can be implemented on Network Simulator II (NS-2) over wireless broadband network. The advantages of this new scheme over the other schemes are more realistic and based on open source program. The result shows that CSVC implementation on MGS mode outperforms CGS mode.

Wireless Sensor Networks (WSN) is an emerging technology for attraction of researchers with its research challenges and various application domains. Today, WSN applications can be used in environmental detection, Monitoring system, medical system, military and industrial monitoring for ability to transform human life in various aspects. Depending on applications used for WSNs, security is the biggest challenges
in WSNs and security aspect is essential for WSNs before designing WSNs. The routing protocols for WSNs need security services for transmission exact and secure data to the users through the network. LEACH (Low Energy Adaptive Clustering Hierarchy) is a routing protocol used in WSNs by arranging sensor nodes into clusters. Every sensor cluster is managed by a Cluster Head (CH) during the network operation such as routing and data aggregation from Cluster Member (CM). Therefore, security and authentication is necessary between CH and CM. However, LEACH is lack of security. This paper presents integration of security and authentication between CH and CM on LEACH routing protocol. For the implementation of this integration, NS-2 simulation software is used and it is necessary to combine security agent into NS-2 tool for WSN. But currently, NS-2 does not support these features. Therefore, the main aim of this paper is to develop security and authentication agent into NS-2 and LEACH protocol for WSNs with the simulation
results.