Rajan Vohra - Academia.edu (original) (raw)
Papers by Rajan Vohra
The quantum transport in symmetric and asymmetric borospherne based molecular junction with adeni... more The quantum transport in symmetric and asymmetric borospherne based molecular junction with adenine has been probed. Adenine is a nucleobase of DNA among the four nucleobases of DNA, adenine is selected because of its excellent transport properties. The DFT-NEGF mathematical approach has been utilized. This was further used to calculate quantum transport parameters such as the I-V curve, transmission spectra, highest occupied molecular orbital (HOMO)- lowest occupied molecular orbital (LUMO) gap (HLG), differential conductance, and transmission pathways. From our research work we have noticed that both symmetric and asymmetric devices exhibit non-linear behavior thus leading to non-differential resistance (NDR). Alos symmetric B40 molecular device has reduced HLG in contrast to asymmetric B40 molecular device. This drop-in HLG is due to a reduction in electron density. A high rectification ratio for the devices is observed at 0.2V. Hence symmetric and asymmetric B40 molecular juncti...
Journal of Materials Research, 2021
The transport properties of molecular wire comprising of B40 fullerene are investigated by employ... more The transport properties of molecular wire comprising of B40 fullerene are investigated by employing density functional theory (DFT) and non-equilibrium green’s function (NEGF) methodology. The quantum transport is evaluated by calculating the density of states, transmission spectra at various bias voltages, molecular energy spectra, HOMO-LUMO gap, current–voltage curve, and transmission pathways. In context to its properties, results show that by increasing the length of molecular wire, the device exhibits rectification ratio and prominent NDR behavior. I–V curve scrutinizes that as the length of wire is increased the curve becomes non-linear. This non-linear behavior is more prominent in the case when the length of wire is increased up to six fullerene cages significant rectification ratio (R.R) and negative differential resistance (NDR) comes into the picture. The excellent negative differential resistance ensures that a device with at least six molecular wires can be used as a t...
Journal of Materials Research, 2020
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Journal of Molecular Modeling, 2020
The possibility of adsorption of toxic phosgene gas (COCl 2) molecule on one of the nucleobase of... more The possibility of adsorption of toxic phosgene gas (COCl 2) molecule on one of the nucleobase of DNA-adenine-has been analyzed using the first principle calculations based on density function theory. In accordance with the geometry of the nucleobase, two possible positions have been considered for effective adsorption of gas molecule. The calculations performed on adsorption energies suggest that the gas molecule is able to physisorb at both the considered positions with negligibly small values of charge transfer. The in-depth analysis of electron charge densities depicts that there is no orbital overlapping between the gas molecule and adenine. We observe a significant variation of transport properties of adenine-based molecular junction on adsorption of phosgene molecule while calculation the transport parameters at both the equilibrium as well as non-equilibrium. Also, the variation of HOMO-LUMO gap of adenine molecule on adsorption of phosgene leads to alteration of current and voltage, thus implying that adenine-based sensor can be effectively utilized to sense the presence of phosgene gas in a given environment. Small adsorption energies and recovery time suggest that the rate of desorption of phosgene is very high; thus, the proposed adenine sensor can be effectively used as a highly stable and selective reusable sensor.
Current Applied Physics, 2020
Electrical charge transport through two basic strands Thymine and Adenine of DNA has been analyze... more Electrical charge transport through two basic strands Thymine and Adenine of DNA has been analyzed using jellium model approach. The FFT-2D computations have been performed for semi empirical Extended Huckel Theory using Atomistix Tool kit to contemplate the charge transport metrics like current and conductance. We have scrutinized the behavior of the devices in the range of-2 V-2 V for a step size of 0.2 V. A prominent observation is the drop in HLGs of Adenine and Thymine, when working as device as compared to their intrinsic values and this is comparative more visible in case of Adenine. The current in the thymine based device exhibit linear increase with voltage in spite of having low conductance. Further the broader transmission peaks represent the strong coupling of electrodes to the scattering molecule (Thymine). The NDR effect of Adenine based device for higher bias can be utilized in various future electronics applications.
Advanced Science Letters, 2018
The scientific interest in field of molecular electronics has raised many folds in last decade to... more The scientific interest in field of molecular electronics has raised many folds in last decade to become the centre stage of contemporary research. The community of researchers working in this domain has been continuously exploring newer molecules, which can replace semiconductors of last century and still continue with the same growth. In this research communiqué, we have implemented molecular junctions using NEGF-EHT approach to elucidate the electronic transport properties of two important strands Adenine and Cytosine of Deoxyribonucleic Acid (DNA) sandwiched between with two Au leads under finite bias conditions. Important revelation include non-linear behaviour exhibited with exponential current rise around zero bias due to kondo assisted resonant tunnelling and temperature invariance over a large range of temperature. G–V graph divulges that conductance of the adenine decrease linearly with the increase in bias voltage initially and then becomes dormant for further increase in...
Journal of Nanoelectronics and Optoelectronics, 2018
Journal of Nanoelectronics and Optoelectronics, 2019
The charge transport through molecular devices using an ensemble of metal electrodes having nucle... more The charge transport through molecular devices using an ensemble of metal electrodes having nucleobase cytosine as the central molecule has been envisaged using a combination of semi-empirical Extended Huckel Theory and Non Equilibrium Green Function (NEGF). FFT-2D computational approach has been effectively applied to elucidate the electron transport characteristics of these molecular devices under both equilibrium as well as non-equilibrium states. The charge transport parameters viz. Device Density of States, Transmission Spectrum, I–V curve, G–V curve and HOMO-LUMO Gap are measured to exhibit the charge transport properties. By comparing the obtained quantum transport properties, we observe that silver remains the best choice among the three electrode materials under study as the molecular device with the silver electrodes exhibits the lower HOMO-LUMO Gap with increased current and conductance for the higher bias voltages in contrast to the other two configurations which show co...
The SIJ Transactions on Computer Networks & Communication Engineering, 2014
Efficient routing is one of the key challenges in the design and performance of a large scale int... more Efficient routing is one of the key challenges in the design and performance of a large scale intradomain network. This paper describes the analysis of dynamic routing protocols IS-IS,IGRP,RIP for the scenario which has fifty number of workstations working on three dissimilar applications(Ftp, Remote Login and Videoconferencing) based on increasing number of packets per sec sent. High speed network is the demand of the user in order to perform multiple tasks with reliability so that its performance is efficient that is why we opted for dissimilar number of packets varying from hundred to thousand and analyzed their effects in the performance of LAN. Simulation is carried out with the help of Optimized Networking Engineering Tool (OPNET) which gives the better edge over the other network simulation tools available. The assessment is based on two parameters namely Ftp Download Response Time and Ftp Upload Response Time. The results concluded that that overall best performance can be achieved with the help of IS-IS protocol other than RIP and IGRP for increasing number of packets in the given scenario and hence it is observed that by sending maximum number of packets there is speed enhancement in the given network with high efficiency.
Journal of Molecular Modeling, 2018
The feasibility of electron transport conduction through a guanine base of DNA was investigated a... more The feasibility of electron transport conduction through a guanine base of DNA was investigated and then compared with another component of DNA, i.e., cytosine. A mathematical approach based on the jellium model using non-equilibrium Green's function combined with semi empirical extended Huckel theory was applied using the Atomistik Tool Kit. This was further used to measure significant transport parameters such as current, conductance, transmission spectra and the HOMO-LUMO gap of the suggested molecular system. An important revelation from our research work is that the cytosine-based molecular device exhibits metallic behavior with current ranging up to 70 μA, and hence establishes itself as a good conductor. On the other hand, the guanine-based device is comparatively less conductive, exhibiting current in the order of 3 μA. Another interesting observation about the guanine-based device is the visibility of a prominent negative differential resistance effect during the positive bias and a tunneling effect during negative bias. The uniform charge transfer through the cytosine device confirms its application as a molecular wire. The observations on the guanine-based device give better insights into its application as a memory device for nano-scale devices.
Nanotechnology Reviews, 2018
The word “nanotechnology” has been exaggerated not only by media but also by scientist groups who... more The word “nanotechnology” has been exaggerated not only by media but also by scientist groups who have overstated the unforeseen benefits of nanotechnology to validate research funding. Even ecologists, who normally remain indulged in doom-and-gloom divinations, use this word to fuel their own motives. Such outcomes lead to widespread misinformation and an unaware public. This research work is a staunch effort to filter the Twitter-based public opinions related to this word. Our results clearly indicate more of positive sentiments attached to the subject of nanotechnology, as trust, anticipation and joy overweigh by many folds the anger, mistrust and anger related to nanotechnology.
Materials Research Express, 2017
In this paper, we analyze the behavior of porphine molecule doped with four atoms of transition m... more In this paper, we analyze the behavior of porphine molecule doped with four atoms of transition metals viz. Boron, Nitrogen and Phosphorus sandwiched in-between the gold electrodes. The extended Huckel theory in conjunction with non-equilibrium Green's function is employed to calculate the ballistic performance of the three molecular devices. We scrutinize density of states, transmission spectrum, current curve and conductance curve to contemplate the behavior of doped molecular junctions. The results are compared for the superiority of junction devices thus formed. The investigation reveals the formation of Coulomb steps at different voltage points with maximum conductance in Au–C16H14N4P4–Au molecular junction.
International Journal of Computer Applications, 2015
The IEEE 802.15.4 the ZigBee protocol finds numerous applications for commercial buildings and ho... more The IEEE 802.15.4 the ZigBee protocol finds numerous applications for commercial buildings and home automation, security, healthcare, medical monitoring, vehicle monitoring, agriculture and environmental monitoring etc. In this paper we have evaluated the effect of topologies variation i.e. Tree, Star and Mesh on load, delay and throughput in different bands using Zigbee wireless sensors by means of OPNET modeler. It is observed that star, tree and mesh topologies have less delay and maximum throughput in 2450MHz band as compared to other bands i.e. 915MHz and 868MHz. The obvious reason for this observation can be less resource overheads in 2450MHz band than other two bands resulting in better network metrics.
2012 IEEE International Conference on Advanced Communication Control and Computing Technologies (ICACCCT), 2012
ABSTRACT Paper investigates that how the performance of the wireless local area networks (WLANs) ... more ABSTRACT Paper investigates that how the performance of the wireless local area networks (WLANs) is effected by the redundancy in a office environment. Environment has been simulated, where many applications are in use at a time and their mutual effects thereof. Here, OPNET has been used to develop a new model suitable for office/company environment. Performance of the WLANs has been evaluated against two types of applications (FTP and DATABASE) for a office/company environment. This model provides us the significant advantage of not having any single point of failure. It has been shown here that there is no degradation of the performance if one of the path has been failed for the communication.
International Journal of Computer Applications, 2013
Quality of Service is an indispensable parameter to evaluate the performance of any network, so r... more Quality of Service is an indispensable parameter to evaluate the performance of any network, so research engrosseson valuing some important QoS parameters for mobile Adhoc network using AntHocNet routing algorithm. MATLAB software version R2011b is used for simulations due to its ease of node deployment and network set up. Simulation is done while varying the number of packets sent as 10, 30, 50, 70 and 90in a network scenario. It is analyzed that AntHocNet provides excellent performance for fewer hops 1, 2 and 3 whereas for increased number of hops9 and 10, it reveals from the routing metrics that use of AntHocNet is more advantageous over the other routing protocols like DSDV, AODV, DSR and TORA.The simulation enactment graphs shows better performance in terms of End-to-end delay, Delay jitter and superlative performance in terms of SINR with extended number of hops when the payload on the source node increases.
2012 2nd IEEE International Conference on Parallel, Distributed and Grid Computing, 2012
ABSTRACT Mobile ad hoc networks (MANETs) are a collection of wireless nodes that dynamically crea... more ABSTRACT Mobile ad hoc networks (MANETs) are a collection of wireless nodes that dynamically create a wireless network among themselves without any infrastructure. Each device in a MANET is free to move independently in any direction, and will therefore change its links to other devices frequently. The objective of this paper is to evaluate the simulation of MANET reactive routing protocols that are Ad Hoc On demand Distance Vector (AODV) and Dynamic Source Routing (DSR) and temporally ordered routing algorithm (TORA) for Guru Nanak Dev University Campus environment using the High Resolution Video Conferencing application. Comparative analysis has been carried out based on the results obtained by simulations with OFDM (802.11a) and Extended Rate PHY (802.11g) physical characteristics in OPNET Modeler version 14.5. Parameters used are Throughput, End to End delay, Routing load and Media Access Delay.
International Journal of Computer Applications, 2012
End-to-end delay of routing packets from the source to destination in a Mobile ad-hoc network is ... more End-to-end delay of routing packets from the source to destination in a Mobile ad-hoc network is a major challenge for a large number of network scientists. This paper presents a new routing approach for mobile ad hoc networks (MANETs) which takes into consideration the Ant Colony Optimization (ACO) technique in conjunction with linear programming approach for minimizing the overall delay in networking environment. Ant colony optimization algorithms have all been inspired by a specific foraging behavior of colonies of the ants, which are able to explore the optimum route connecting the colony"s nest with a source of food. It has been observed that the mean end-to-end delay of a link from the source to the destination is one of the most important metric for a MANET. The other metrics that have been considered and evaluated are utilization or efficiency of link, arrival rate and service rate with respect to link delay. The simulation tool used for our model is MATLAB 7.5.
International Journal of Computer Applications, 2012
In order to analyze the performance of Wireless Local Area Networks (WLANs) effectively, it is im... more In order to analyze the performance of Wireless Local Area Networks (WLANs) effectively, it is important to identify those network settings that can cause the networks performance to go from good to poor. Low throughput, high packet loss rate, delayed round trip time (RTT), increased retransmissions, and increased collisions are the detrimental attributes to look for, when poor network performance is encountered. In this paper, our main focus is to analyze and evaluate the role of the media access delay as well as processing delay towards the performance of WLANs. The simulation tool OPNET has been used for fine-tuning the WLAN parameters and simulation demonstrate that WLAN performance can be enhanced by tuning different metrics such as buffer size, fragmentation threshold and request to send (RTS) thresholds. In this paper, we emphasized on buffer size and its subsequent effect on service quality. By varying the buffer size to a value other than specified in the standards, will reduce WLAN delay, media access delay with minutest changes observed in throughput.
Procedia Engineering, 2012
Procedia Engineering, 2012
The quantum transport in symmetric and asymmetric borospherne based molecular junction with adeni... more The quantum transport in symmetric and asymmetric borospherne based molecular junction with adenine has been probed. Adenine is a nucleobase of DNA among the four nucleobases of DNA, adenine is selected because of its excellent transport properties. The DFT-NEGF mathematical approach has been utilized. This was further used to calculate quantum transport parameters such as the I-V curve, transmission spectra, highest occupied molecular orbital (HOMO)- lowest occupied molecular orbital (LUMO) gap (HLG), differential conductance, and transmission pathways. From our research work we have noticed that both symmetric and asymmetric devices exhibit non-linear behavior thus leading to non-differential resistance (NDR). Alos symmetric B40 molecular device has reduced HLG in contrast to asymmetric B40 molecular device. This drop-in HLG is due to a reduction in electron density. A high rectification ratio for the devices is observed at 0.2V. Hence symmetric and asymmetric B40 molecular juncti...
Journal of Materials Research, 2021
The transport properties of molecular wire comprising of B40 fullerene are investigated by employ... more The transport properties of molecular wire comprising of B40 fullerene are investigated by employing density functional theory (DFT) and non-equilibrium green’s function (NEGF) methodology. The quantum transport is evaluated by calculating the density of states, transmission spectra at various bias voltages, molecular energy spectra, HOMO-LUMO gap, current–voltage curve, and transmission pathways. In context to its properties, results show that by increasing the length of molecular wire, the device exhibits rectification ratio and prominent NDR behavior. I–V curve scrutinizes that as the length of wire is increased the curve becomes non-linear. This non-linear behavior is more prominent in the case when the length of wire is increased up to six fullerene cages significant rectification ratio (R.R) and negative differential resistance (NDR) comes into the picture. The excellent negative differential resistance ensures that a device with at least six molecular wires can be used as a t...
Journal of Materials Research, 2020
<jats:p><jats:fig position="anchor"><jats:graphic xmlns:xlink="http... more <jats:p><jats:fig position="anchor"><jats:graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" mimetype="image" xlink:href="S0884291420002058_figAb.png" /></jats:fig></jats:p>
Journal of Molecular Modeling, 2020
The possibility of adsorption of toxic phosgene gas (COCl 2) molecule on one of the nucleobase of... more The possibility of adsorption of toxic phosgene gas (COCl 2) molecule on one of the nucleobase of DNA-adenine-has been analyzed using the first principle calculations based on density function theory. In accordance with the geometry of the nucleobase, two possible positions have been considered for effective adsorption of gas molecule. The calculations performed on adsorption energies suggest that the gas molecule is able to physisorb at both the considered positions with negligibly small values of charge transfer. The in-depth analysis of electron charge densities depicts that there is no orbital overlapping between the gas molecule and adenine. We observe a significant variation of transport properties of adenine-based molecular junction on adsorption of phosgene molecule while calculation the transport parameters at both the equilibrium as well as non-equilibrium. Also, the variation of HOMO-LUMO gap of adenine molecule on adsorption of phosgene leads to alteration of current and voltage, thus implying that adenine-based sensor can be effectively utilized to sense the presence of phosgene gas in a given environment. Small adsorption energies and recovery time suggest that the rate of desorption of phosgene is very high; thus, the proposed adenine sensor can be effectively used as a highly stable and selective reusable sensor.
Current Applied Physics, 2020
Electrical charge transport through two basic strands Thymine and Adenine of DNA has been analyze... more Electrical charge transport through two basic strands Thymine and Adenine of DNA has been analyzed using jellium model approach. The FFT-2D computations have been performed for semi empirical Extended Huckel Theory using Atomistix Tool kit to contemplate the charge transport metrics like current and conductance. We have scrutinized the behavior of the devices in the range of-2 V-2 V for a step size of 0.2 V. A prominent observation is the drop in HLGs of Adenine and Thymine, when working as device as compared to their intrinsic values and this is comparative more visible in case of Adenine. The current in the thymine based device exhibit linear increase with voltage in spite of having low conductance. Further the broader transmission peaks represent the strong coupling of electrodes to the scattering molecule (Thymine). The NDR effect of Adenine based device for higher bias can be utilized in various future electronics applications.
Advanced Science Letters, 2018
The scientific interest in field of molecular electronics has raised many folds in last decade to... more The scientific interest in field of molecular electronics has raised many folds in last decade to become the centre stage of contemporary research. The community of researchers working in this domain has been continuously exploring newer molecules, which can replace semiconductors of last century and still continue with the same growth. In this research communiqué, we have implemented molecular junctions using NEGF-EHT approach to elucidate the electronic transport properties of two important strands Adenine and Cytosine of Deoxyribonucleic Acid (DNA) sandwiched between with two Au leads under finite bias conditions. Important revelation include non-linear behaviour exhibited with exponential current rise around zero bias due to kondo assisted resonant tunnelling and temperature invariance over a large range of temperature. G–V graph divulges that conductance of the adenine decrease linearly with the increase in bias voltage initially and then becomes dormant for further increase in...
Journal of Nanoelectronics and Optoelectronics, 2018
Journal of Nanoelectronics and Optoelectronics, 2019
The charge transport through molecular devices using an ensemble of metal electrodes having nucle... more The charge transport through molecular devices using an ensemble of metal electrodes having nucleobase cytosine as the central molecule has been envisaged using a combination of semi-empirical Extended Huckel Theory and Non Equilibrium Green Function (NEGF). FFT-2D computational approach has been effectively applied to elucidate the electron transport characteristics of these molecular devices under both equilibrium as well as non-equilibrium states. The charge transport parameters viz. Device Density of States, Transmission Spectrum, I–V curve, G–V curve and HOMO-LUMO Gap are measured to exhibit the charge transport properties. By comparing the obtained quantum transport properties, we observe that silver remains the best choice among the three electrode materials under study as the molecular device with the silver electrodes exhibits the lower HOMO-LUMO Gap with increased current and conductance for the higher bias voltages in contrast to the other two configurations which show co...
The SIJ Transactions on Computer Networks & Communication Engineering, 2014
Efficient routing is one of the key challenges in the design and performance of a large scale int... more Efficient routing is one of the key challenges in the design and performance of a large scale intradomain network. This paper describes the analysis of dynamic routing protocols IS-IS,IGRP,RIP for the scenario which has fifty number of workstations working on three dissimilar applications(Ftp, Remote Login and Videoconferencing) based on increasing number of packets per sec sent. High speed network is the demand of the user in order to perform multiple tasks with reliability so that its performance is efficient that is why we opted for dissimilar number of packets varying from hundred to thousand and analyzed their effects in the performance of LAN. Simulation is carried out with the help of Optimized Networking Engineering Tool (OPNET) which gives the better edge over the other network simulation tools available. The assessment is based on two parameters namely Ftp Download Response Time and Ftp Upload Response Time. The results concluded that that overall best performance can be achieved with the help of IS-IS protocol other than RIP and IGRP for increasing number of packets in the given scenario and hence it is observed that by sending maximum number of packets there is speed enhancement in the given network with high efficiency.
Journal of Molecular Modeling, 2018
The feasibility of electron transport conduction through a guanine base of DNA was investigated a... more The feasibility of electron transport conduction through a guanine base of DNA was investigated and then compared with another component of DNA, i.e., cytosine. A mathematical approach based on the jellium model using non-equilibrium Green's function combined with semi empirical extended Huckel theory was applied using the Atomistik Tool Kit. This was further used to measure significant transport parameters such as current, conductance, transmission spectra and the HOMO-LUMO gap of the suggested molecular system. An important revelation from our research work is that the cytosine-based molecular device exhibits metallic behavior with current ranging up to 70 μA, and hence establishes itself as a good conductor. On the other hand, the guanine-based device is comparatively less conductive, exhibiting current in the order of 3 μA. Another interesting observation about the guanine-based device is the visibility of a prominent negative differential resistance effect during the positive bias and a tunneling effect during negative bias. The uniform charge transfer through the cytosine device confirms its application as a molecular wire. The observations on the guanine-based device give better insights into its application as a memory device for nano-scale devices.
Nanotechnology Reviews, 2018
The word “nanotechnology” has been exaggerated not only by media but also by scientist groups who... more The word “nanotechnology” has been exaggerated not only by media but also by scientist groups who have overstated the unforeseen benefits of nanotechnology to validate research funding. Even ecologists, who normally remain indulged in doom-and-gloom divinations, use this word to fuel their own motives. Such outcomes lead to widespread misinformation and an unaware public. This research work is a staunch effort to filter the Twitter-based public opinions related to this word. Our results clearly indicate more of positive sentiments attached to the subject of nanotechnology, as trust, anticipation and joy overweigh by many folds the anger, mistrust and anger related to nanotechnology.
Materials Research Express, 2017
In this paper, we analyze the behavior of porphine molecule doped with four atoms of transition m... more In this paper, we analyze the behavior of porphine molecule doped with four atoms of transition metals viz. Boron, Nitrogen and Phosphorus sandwiched in-between the gold electrodes. The extended Huckel theory in conjunction with non-equilibrium Green's function is employed to calculate the ballistic performance of the three molecular devices. We scrutinize density of states, transmission spectrum, current curve and conductance curve to contemplate the behavior of doped molecular junctions. The results are compared for the superiority of junction devices thus formed. The investigation reveals the formation of Coulomb steps at different voltage points with maximum conductance in Au–C16H14N4P4–Au molecular junction.
International Journal of Computer Applications, 2015
The IEEE 802.15.4 the ZigBee protocol finds numerous applications for commercial buildings and ho... more The IEEE 802.15.4 the ZigBee protocol finds numerous applications for commercial buildings and home automation, security, healthcare, medical monitoring, vehicle monitoring, agriculture and environmental monitoring etc. In this paper we have evaluated the effect of topologies variation i.e. Tree, Star and Mesh on load, delay and throughput in different bands using Zigbee wireless sensors by means of OPNET modeler. It is observed that star, tree and mesh topologies have less delay and maximum throughput in 2450MHz band as compared to other bands i.e. 915MHz and 868MHz. The obvious reason for this observation can be less resource overheads in 2450MHz band than other two bands resulting in better network metrics.
2012 IEEE International Conference on Advanced Communication Control and Computing Technologies (ICACCCT), 2012
ABSTRACT Paper investigates that how the performance of the wireless local area networks (WLANs) ... more ABSTRACT Paper investigates that how the performance of the wireless local area networks (WLANs) is effected by the redundancy in a office environment. Environment has been simulated, where many applications are in use at a time and their mutual effects thereof. Here, OPNET has been used to develop a new model suitable for office/company environment. Performance of the WLANs has been evaluated against two types of applications (FTP and DATABASE) for a office/company environment. This model provides us the significant advantage of not having any single point of failure. It has been shown here that there is no degradation of the performance if one of the path has been failed for the communication.
International Journal of Computer Applications, 2013
Quality of Service is an indispensable parameter to evaluate the performance of any network, so r... more Quality of Service is an indispensable parameter to evaluate the performance of any network, so research engrosseson valuing some important QoS parameters for mobile Adhoc network using AntHocNet routing algorithm. MATLAB software version R2011b is used for simulations due to its ease of node deployment and network set up. Simulation is done while varying the number of packets sent as 10, 30, 50, 70 and 90in a network scenario. It is analyzed that AntHocNet provides excellent performance for fewer hops 1, 2 and 3 whereas for increased number of hops9 and 10, it reveals from the routing metrics that use of AntHocNet is more advantageous over the other routing protocols like DSDV, AODV, DSR and TORA.The simulation enactment graphs shows better performance in terms of End-to-end delay, Delay jitter and superlative performance in terms of SINR with extended number of hops when the payload on the source node increases.
2012 2nd IEEE International Conference on Parallel, Distributed and Grid Computing, 2012
ABSTRACT Mobile ad hoc networks (MANETs) are a collection of wireless nodes that dynamically crea... more ABSTRACT Mobile ad hoc networks (MANETs) are a collection of wireless nodes that dynamically create a wireless network among themselves without any infrastructure. Each device in a MANET is free to move independently in any direction, and will therefore change its links to other devices frequently. The objective of this paper is to evaluate the simulation of MANET reactive routing protocols that are Ad Hoc On demand Distance Vector (AODV) and Dynamic Source Routing (DSR) and temporally ordered routing algorithm (TORA) for Guru Nanak Dev University Campus environment using the High Resolution Video Conferencing application. Comparative analysis has been carried out based on the results obtained by simulations with OFDM (802.11a) and Extended Rate PHY (802.11g) physical characteristics in OPNET Modeler version 14.5. Parameters used are Throughput, End to End delay, Routing load and Media Access Delay.
International Journal of Computer Applications, 2012
End-to-end delay of routing packets from the source to destination in a Mobile ad-hoc network is ... more End-to-end delay of routing packets from the source to destination in a Mobile ad-hoc network is a major challenge for a large number of network scientists. This paper presents a new routing approach for mobile ad hoc networks (MANETs) which takes into consideration the Ant Colony Optimization (ACO) technique in conjunction with linear programming approach for minimizing the overall delay in networking environment. Ant colony optimization algorithms have all been inspired by a specific foraging behavior of colonies of the ants, which are able to explore the optimum route connecting the colony"s nest with a source of food. It has been observed that the mean end-to-end delay of a link from the source to the destination is one of the most important metric for a MANET. The other metrics that have been considered and evaluated are utilization or efficiency of link, arrival rate and service rate with respect to link delay. The simulation tool used for our model is MATLAB 7.5.
International Journal of Computer Applications, 2012
In order to analyze the performance of Wireless Local Area Networks (WLANs) effectively, it is im... more In order to analyze the performance of Wireless Local Area Networks (WLANs) effectively, it is important to identify those network settings that can cause the networks performance to go from good to poor. Low throughput, high packet loss rate, delayed round trip time (RTT), increased retransmissions, and increased collisions are the detrimental attributes to look for, when poor network performance is encountered. In this paper, our main focus is to analyze and evaluate the role of the media access delay as well as processing delay towards the performance of WLANs. The simulation tool OPNET has been used for fine-tuning the WLAN parameters and simulation demonstrate that WLAN performance can be enhanced by tuning different metrics such as buffer size, fragmentation threshold and request to send (RTS) thresholds. In this paper, we emphasized on buffer size and its subsequent effect on service quality. By varying the buffer size to a value other than specified in the standards, will reduce WLAN delay, media access delay with minutest changes observed in throughput.
Procedia Engineering, 2012
Procedia Engineering, 2012