The document proposes a wavelength and converter assignment scheme for wavelength-routed networks to decrease lightpath blocking probability with a limited number of converters. The key points are:
1) The scheme avoids contention among multiple lightpath requests by making each node-pair perform wavelength conversion at different intermediate nodes, based on the intermediate nodes' converter usage history.
2) It assigns wavelength conversion costs to intermediate nodes based on their historical converter usage and number of idle converters, aiming to use different converters for different node-pairs and keep more converters available.
3) Simulation results show the proposed scheme decreases blocking probability by 44-83% compared to conventional schemes, and needs 1-2 fewer converters per node to achieve near-
Engineering Research Publication
Best International Journals, High Impact Journals,
International Journal of Engineering & Technical Research
ISSN : 2321-0869 (O) 2454-4698 (P)
www.erpublication.org
Implementing Energy Efficient Strategies in the MANET on-demand routing Proto...IJEEE
Mobile Ad-hoc networks are self-configuring multi-hop wireless networks where, the structure of the network changes dynamically. Because of the nodes in the MANET are mobile and battery operated, energy optimization is one of the major constraints in the MANET. Failure of some nodes operation can greatly impede the performance of the network and even affect the basic availability of the network, i.e., routing. To improve the lifetime of these networks can be improving the energy levels of the individual nodes of the network. This paper presents an analysis of the effects of different design choices for this on- demand routing protocols DSR and AODV in wireless ad hoc networks. In this paper, the energy efficient strategies are implemented in the AODV and DSR protocols to improve the life time of the Mobile ad hoc network. The CBEER-NN is developed using the existing DSR protocol and the AO- EEDTR is developed using the existing AODV protocol. GloMoSIM simulator is used to simulate the proposed MANET environment. This paper also compares the existing DSR and AODV protocols with proposed CBEER- NN and AO-EEDTR protocols. From the simulated results, this paper concludes that the proposed CBEER-NN and AO- EEDTR protocols are improving the life time of the network by improving the average residual energy of the nodes over the existing DSR and AO-EEDTR protocols.
Mobile Ad-Hoc Network (MANET) is a self-configuring network of mobile devices connected through wireless. Nowadays mobile devices in mobile Ad-hoc network are battery operated. Battery is an important factor in MANET. Dynamic topology of mobile ad-hoc network and limited battery capacity are constrained on network life time. In this paper, we have presented variants of power aware techniques in an on-demand reactive routing protocol i.e. AODV which aims to prolong network lifetime. AODV is reactive protocol and it establish route on demand.
The Impact of Signal Strength over Routing Protocols in Wireless NetworksDr. Amarjeet Singh
In ad hoc routing protocols the source node
may need an intermediate nodes to transmit the packets into
the destination if the destination is not within transmission
range of the source. This paper studies the impact of signal
strength of nodes over ad hoc routing protocols and explains
an important effect of signal strength on ad hoc routing
protocols in four different directions including the routes and
the nodes. As a result the study give an important
improvement in ad hoc routing protocols when using signal
strength compared to other ad hoc routing protocols without
considering signal strength.
Long-Term Evolution (LTE), an emerging and promising fourth generation mobile technology, is expected
to offer ubiquitous broadband access to the mobile subscribers. In this paper, the performance of Frame
Level Scheduler (FLS), Exponential (EXP) rule, Logarithmic (LOG) rule and Maximum-Largest Weighted
Delay First (M-LWDF) packet scheduling algorithms has been studied in the downlink 3GPP LTE cellular
network. To this aim, a single cell with interference scenario has been considered. The performance
evaluation is made by varying the number of UEs ranging from 10 to 50 (Case 1) and user speed in the
range of [3, 120] km/h (Case 2). Results show that while the number of UEs and user speed increases, the
performance of the considered scheduling schemes degrades and in both case FLS outperforms other three
schemes in terms of several performance indexes such as average throughput, packet loss ratio (PLR),
packet delay and fairness index.
Impact of le arrivals and departures on bufferingenioustech
Dear Students
Ingenious techno Solution offers an expertise guidance on you Final Year IEEE & Non- IEEE Projects on the following domain
JAVA
.NET
EMBEDDED SYSTEMS
ROBOTICS
MECHANICAL
MATLAB etc
For further details contact us:
enquiry@ingenioustech.in
044-42046028 or 8428302179.
Ingenious Techno Solution
#241/85, 4th floor
Rangarajapuram main road,
Kodambakkam (Power House)
http://www.ingenioustech.in/
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
A MANET is an autonomous collection of mobile users that communicate over relatively bandwidth constrained wireless links. When designing mobile ad hoc networks, several interesting and difficult problems arise because of the shared nature of the wireless medium, limited transmission power (range) of wireless devices, node mobility, and battery limitations. This paper aims at providing a new schema to improve Dynamic Source Routing (DSR) Protocol. The aim
behind the proposed enhancement is to find the best route in acceptable time limit without having broadcast storm. Moreover, O-DSR enables network not only to overcome congestion but also maximize the lifetime of mobile nodes. Some simulations results show that the Route Request (RREQ) and the Control Packet Overhead decrease by 15% when O-DSR is used, consequently. Also the global energy consumption in O-DSR is lower until to 60 % , which leads to a long lifetime of the network.
Engineering Research Publication
Best International Journals, High Impact Journals,
International Journal of Engineering & Technical Research
ISSN : 2321-0869 (O) 2454-4698 (P)
www.erpublication.org
Implementing Energy Efficient Strategies in the MANET on-demand routing Proto...IJEEE
Mobile Ad-hoc networks are self-configuring multi-hop wireless networks where, the structure of the network changes dynamically. Because of the nodes in the MANET are mobile and battery operated, energy optimization is one of the major constraints in the MANET. Failure of some nodes operation can greatly impede the performance of the network and even affect the basic availability of the network, i.e., routing. To improve the lifetime of these networks can be improving the energy levels of the individual nodes of the network. This paper presents an analysis of the effects of different design choices for this on- demand routing protocols DSR and AODV in wireless ad hoc networks. In this paper, the energy efficient strategies are implemented in the AODV and DSR protocols to improve the life time of the Mobile ad hoc network. The CBEER-NN is developed using the existing DSR protocol and the AO- EEDTR is developed using the existing AODV protocol. GloMoSIM simulator is used to simulate the proposed MANET environment. This paper also compares the existing DSR and AODV protocols with proposed CBEER- NN and AO-EEDTR protocols. From the simulated results, this paper concludes that the proposed CBEER-NN and AO- EEDTR protocols are improving the life time of the network by improving the average residual energy of the nodes over the existing DSR and AO-EEDTR protocols.
Mobile Ad-Hoc Network (MANET) is a self-configuring network of mobile devices connected through wireless. Nowadays mobile devices in mobile Ad-hoc network are battery operated. Battery is an important factor in MANET. Dynamic topology of mobile ad-hoc network and limited battery capacity are constrained on network life time. In this paper, we have presented variants of power aware techniques in an on-demand reactive routing protocol i.e. AODV which aims to prolong network lifetime. AODV is reactive protocol and it establish route on demand.
The Impact of Signal Strength over Routing Protocols in Wireless NetworksDr. Amarjeet Singh
In ad hoc routing protocols the source node
may need an intermediate nodes to transmit the packets into
the destination if the destination is not within transmission
range of the source. This paper studies the impact of signal
strength of nodes over ad hoc routing protocols and explains
an important effect of signal strength on ad hoc routing
protocols in four different directions including the routes and
the nodes. As a result the study give an important
improvement in ad hoc routing protocols when using signal
strength compared to other ad hoc routing protocols without
considering signal strength.
Long-Term Evolution (LTE), an emerging and promising fourth generation mobile technology, is expected
to offer ubiquitous broadband access to the mobile subscribers. In this paper, the performance of Frame
Level Scheduler (FLS), Exponential (EXP) rule, Logarithmic (LOG) rule and Maximum-Largest Weighted
Delay First (M-LWDF) packet scheduling algorithms has been studied in the downlink 3GPP LTE cellular
network. To this aim, a single cell with interference scenario has been considered. The performance
evaluation is made by varying the number of UEs ranging from 10 to 50 (Case 1) and user speed in the
range of [3, 120] km/h (Case 2). Results show that while the number of UEs and user speed increases, the
performance of the considered scheduling schemes degrades and in both case FLS outperforms other three
schemes in terms of several performance indexes such as average throughput, packet loss ratio (PLR),
packet delay and fairness index.
Impact of le arrivals and departures on bufferingenioustech
Dear Students
Ingenious techno Solution offers an expertise guidance on you Final Year IEEE & Non- IEEE Projects on the following domain
JAVA
.NET
EMBEDDED SYSTEMS
ROBOTICS
MECHANICAL
MATLAB etc
For further details contact us:
enquiry@ingenioustech.in
044-42046028 or 8428302179.
Ingenious Techno Solution
#241/85, 4th floor
Rangarajapuram main road,
Kodambakkam (Power House)
http://www.ingenioustech.in/
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
A MANET is an autonomous collection of mobile users that communicate over relatively bandwidth constrained wireless links. When designing mobile ad hoc networks, several interesting and difficult problems arise because of the shared nature of the wireless medium, limited transmission power (range) of wireless devices, node mobility, and battery limitations. This paper aims at providing a new schema to improve Dynamic Source Routing (DSR) Protocol. The aim
behind the proposed enhancement is to find the best route in acceptable time limit without having broadcast storm. Moreover, O-DSR enables network not only to overcome congestion but also maximize the lifetime of mobile nodes. Some simulations results show that the Route Request (RREQ) and the Control Packet Overhead decrease by 15% when O-DSR is used, consequently. Also the global energy consumption in O-DSR is lower until to 60 % , which leads to a long lifetime of the network.
Clustering based Time Slot Assignment Protocol for Improving Performance in U...journal ijrtem
Recently, numerous approaches have been proposed for designing medium access control (MAC)
in underwater acoustic networks (UANs). Some of those works tried to adapt MAC protocols proposed for
terrestrial networks. However, unique environmental characteristics of UANs make the MAC protocols hard to be
used in the UANs and degrade network performance. In order to improve network performance, COD-TS MAC
protocol was proposed. COD-TS focuses on both single hop and multi-hop mode and utilizes CDMA for
exchanging schedule information between cluster heads. COD-TS has shortcomings such as collisions, additional
energy consumption by exchanging schedule information and near-far effect of CDMA. To overcome above
shortcomings, we propose a clustering-based time slot assignment protocol. In the proposed protocol, nodes are
clustered, and each cluster head performs two-hop neighbor cluster discovery operation. And then, a cluster head
obtains its own relative position information. Finally, the cluster head assigns its own time slot for data
transmission based on the information. Simulation results show that the proposed protocol has always better
performance compared to the COD-TS.
Performance Comparison of AODV, DSR and LAR1 in Mobile Ad-hoc Network based o...IOSR Journals
Abstract: In the last couple of years, the use of wireless networks has become more and more popular. A
MANET is a collection of self-organizing mobile nodes which is infrastructure less, autonomous, and standalone
networks. Each node in a MANET is free to move independently in any direction and will therefore change its
links to other devices frequently. Each must forward traffic unrelated to its own use and therefore be a router.
Simulation result has been obtained by a performance comparison of three routing protocols i.e. Ad hoc Ondemand
Distance Vector (AODV), Dynamic Source Routing (DSR), Location Aided Routing (LAR1) against
Simulation time. The Result is obtained using QualNet simulator version 6.1. Different protocols are evaluated
based on measures such as Average End to End delay (s), Average Jitter(s), and Packet delivery ratio.
Keywords: MANET, AODV, DSR, LAR1, QualNet 6.1
A cross layer delay-aware node disjoint multipath routing algorithm for mobil...ijwmn
Mobile Ad Hoc Networks (MANETS) require reliable routing and Quality of Service(QoS) mechanism to
support diverse applications with varying and stringent requirements for delay, jitter, bandwidth, packets
loss. Routing protocols such as AODV, AOMDV, DSR and OLSR use shortest path with minimum hop
count as the main metric for path selection, hence are not suitable for delay sensitive real time
applications. To support such applications delay constrained routing protocols are employed. These
Protocols makes path selection between source and destination based on the delay over the discovered
links during routing discovery and routing table calculations. We propose a variation of a node-disjoint
Multipath QoS Routing protocol called Cross Layer Delay aware Node Disjoint Multipath AODV (CLDMAODV)
based on delay constraint. It employs cross-layer communications between MAC and routing
layers to achieve link and channel-awareness. It regularly updates the path status in terms of lowest delay
incurred at each intermediate node. Performance of the proposed protocol is compared with single path
AODV and NDMR protocols. Proposed CLDM-AODV is superior in terms of better packet delivery and
reduced overhead between intermediate nodes.
LEACH is a hierarchical protocol in which most nodes transmit to cluster heads, and the cluster heads aggregate and compress the data and forward it to the base station (sink).In LEACH, a TDMA-based MAC protocol is integrated with clustering and a simple “routing” protocol. The goal of LEACH is to lower the energy consumption required to create and maintain clusters or to use the energy of the nodes in such a manner so as to improve the life time of a wireless sensor network. In this paper we are presenting an overview of the different protocol changes made in LEACH to improve network lifetime, throughput, coverage area of network etc.
LTE QOS DYNAMIC RESOURCE BLOCK ALLOCATION WITH POWER SOURCE LIMITATION AND QU...IJCNCJournal
3GPP has defined the long term evolution (LTE) for 3G radio access in order to maintain the future
competitiveness for 3G technology, the system provides the capability of supporting a mixture of services
with different quality of service (QoS) requirements. This paper proposes a new cross-layer scheduling
algorithm to satisfy better QoS parameters for real time applications. The proposed algorithm takes care of
allocating resource blocks (RBs) with different modulation and coding schemes (MCS) according to target
bit error rate (BER), user equipment supportable MCS, queue stability constraints and available transmit
power constraints. The proposed algorithm has been valued, compared with an earlier allocation algorithm
in terms of service rate and packet delay and showed better performance regards the real time
applications.
P ERFORMANCE C OMPARISON OF R OUTING P ROTOCOLS IN M OBILE A D H OC N E...ijujournal
Routing protocols have
an important
role in any
Mobile Ad Hoc Network
(MANET).
Researchers
have
elaborated several routing protocols that possess different performance levels
. In this
p
aper
we
give a
performance evaluation of
AODV,
DSR,
DSDV
, OLSR and DYMO
routing protocol
s
in
Mobile Ad Hoc
Networks
(MANETS)
to
determine
the best
in different scenarios
. We
analyse
these
MANET
routing
protocols by
using
NS
-
2 simulator
. We specify how
the
Number of No
d
es
parameter influences
their
performance. In this study
,
performance is
calculated
in terms
of Packet Delivery Ratio,
Average
End to
End Delay, Normalised Routing Load and Average Throughput
Performance comparison of routing protocols in mobile ad hoc networksijujournal
Routing protocols have an important role in any Mobile Ad Hoc Network (MANET). Researchers have elaborated several routing protocols that possess different performance levels. In this paper we give a performance evaluation of AODV, DSR, DSDV, OLSR and DYMO routing protocols in Mobile Ad Hoc
Networks (MANETS) to determine the best in different scenarios. We analyse these MANET routing protocols by using NS-2 simulator. We specify how the Number of Nodes parameter influences their performance. In this study, performance is calculated in terms of Packet Delivery Ratio, Average End to End Delay, Normalised Routing Load and Average Throughput.
Rate Adaptation for Time Varying Channels Using Distributed Relay Selectionpaperpublications3
Abstract: Fixed systems used in cooperative communication suffer from multiplexing loss and low spectral efficiency due to the half duplex constraint of relays. To improve the multiplexing gain, successive relaying is proposed. This allows concurrent transmission of the source and relays. However, the severe inter-relay interference becomes a key challenge. Here Rate Adaptation for Time Varying Channels Using Distributed Relay Selection is proposed, which is capable of adapting the relay’s rate using distributed relay selection.
Performance Analysis of Enhanced Opportunistic Minimum Cost Routingin Mobile ...IJERA Editor
Mobile Ad-Hoc Network (MANET) is a collection of wireless mobile nodes forming a temporary network with
infrastructure less environment to establish a data transmission between nodes within the network. A routing
protocol is used to discover routes between nodes. In this paper, we study the three existing routing protocols
namely AODV, DSDV and DSR to analyze theirperformance based on set of parameters.AODV and DSR
deliver almost all the packets compared to DSDV. Hence we try to modify the AODVprotocol and use in the
cooperative transmission.
In this paper, we study the cooperative transmission at the network layer and cooperative diversity at the
physical layer as a joint optimization of the transmission power in a Mobile Ad-Hoc Network (MANET) with
static channel. However due to variable wireless channels static routing is suboptimal. Proposed protocol
proactively selects forwarding nodes that work cooperatively forwarding the packet towards the destination.
Cooperative transmission side diversity helps in reducing interference. Diversity can be achieved at the physical
layer by coordinating the multiple nodes. Nodes are equipped with Omni-directional antenna and take the
advantages of transmission side diversity to achieve energy saving, under the assumption that channel gains are
available at the transmitters.
The proposed Opportunistic Minimum Cost Cooperative Transmission Shortest Path (OMCTSP) algorithms
select the best optimum route with minimum cost in terms of energy, number of hops, available bandwidth, link
quality (SNR) and outage probability. As the network becomes larger, finding optimal routes becomes
computationally intractable as the complexity of the dynamic programming (DP) approach increases as o (22n)
where n is the number of nodes in the networks. Hence we develop two suboptimal algorithms have complexity
of o (n2) perform as same as optimal algorithm. Also developthe Opportunistic Cooperative Routing in MANET
(O_CORMAN), which is a network layer opportunistic routing scheme for mobile ad hoc networks. Nodes in
the network use the components proactive routing protocol, forwarder list update and local re-transmission. We
evaluate the performance using NS 2.32 simulator there is significant performance improvement with respect to
energy, throughput packet delivery, and delay compared with Modified AODV (OMCTSP).
Design and implementation of low latency weighted round robin (ll wrr) schedu...ijwmn
Today’s wireless broadband networks are required to provide QoS guarantee as well as fairness to
different kinds of traffic. Recent wireless standards (such as LTE and WiMAX) have special provisions at
MAC layer for differentiating and scheduling data traffic for achieving QoS. The main focus of this paper is
concerned with high speed packet queuing/scheduling at central node such as base station (BS) or router to
handle network traffic. This paper proposes novel packet queuing scheme termed as Low Latency
Weighted Round Robin (LL-WRR) which is simple and effective amendment to weighted round robin (WRR)
for achieving low latency and improved fairness. Proposed LL-WRR queue scheduling scheme is
implemented in NS-2 considering IEEE 802.16 network [1] with real time video and Constant Bit Rate
(CBR) audio traffic connections. Simulation results show improvement obtained in latency and fairness
using LL-WRR. The proposed scheme introduces extra complexity of computing coefficient but its overall
impact is very small.
Modeling and Simulation of Wavelength-Routed optical Networksijceronline
All-optical Wavelength Division Multiplexing (WDM) networks providing extremely large bandwidths are among the most promising solutions to the increasing need for high-speed data transport. A lightpath has a specific route and one or more wavelengths through which the information is routed from the source to the destination node. In wavelength-routed optical networks, data are transmitted solely in the optical domain along lightpaths from source to destination without being converted into the electronic form and each lightpath is allowed to use the same wavelength on all the links along its path. This restriction is known as the wavelength continuity constraint. And it leads to an issue called as blocking in networks. Optical wavelength conversion with suitable Routing and wavelength assignment (RWA) can increase the performance and capacity of optical networks by eliminating this restriction and relaxing the wavelength continuity constraint. In this research, we analyze the problem of placing a limited number of wavelength converters in a mesh network using Weighted Maximum Segment Length (WMSL) converter placement algorithm. It employs Least-Loaded Routing and First-Fit (LLR-FF) RWA algorithm. It is tested on varying number of nodes in network and its respective blocking probabilities are calculated. The proposed algorithm provides the minimum blocking probability on optimal wavelength converters placement.
Single Mode Optical Fiber in Rof System Using DWDMIJERA Editor
Performance analysis was carried out to find the effect of crosstalk in a WDM system. Firstly, analysis of BER
was carried out without crosstalk. Then analysis of BER with crosstalk was done. Using equation for crosstalk,
number of channels was plotted using matlab. System parameters were optimized for a particular crosstalk.
Objective of the thesis work
Performance Analysis is carried out to find the effect of crosstalk due to optical cross connect in a DWDM
system considering a WDM based optical cross connect (OXC). An analysis is carried out to find the amount of
crosstalk due to OXC. The bit error rate performance degradation due to crosstalk is evaluated for OXC
parameter and number of wavelengths per fiber. The optimum parameters such as optimum number of channels
and hops are determined.
A Novel Timer-Based Hybrid Rerouting Algorithm for Improving Resource Utiliza...IJERA Editor
In this paper we investigate hybrid rerouting and minimization of incurred service disruption period due to
rerouting in Wavelength Division Multiplexed (WDM) transparent optical network. One limitation of such a
network is the wavelength continuity constraint which does not allow a circuit to be placed on a non
wavelength-continuous route. The impact of this constraint might have a severe consequence on the
performance of transparent optical networks especially in terms of rejection ratio ant it is especially severe when
traffic demands are unpredictable and characterized by random arrivals and departures. To alleviate the impact
of these constraints, either wavelength conversion or traffic rerouting can be used. Since, in the foreseeable
future, wavelength conversion is expected to remain an expensive technology, traffic rerouting is an attractive
alternative solution. Thus, we here propose to employ hybrid rerouting to improve the network performances.
Hybrid rerouting combines passive and active rerouting. Through simulation results, the performances of the
proposed algorithm in terms of rejection ratio are demonstrated to be promising while rerouting a small number
of already established lightpaths using Lightpath ReRouting (LRR). By rerouting a small number of existing
lightpaths using LRR, we hope that the incurred service disruption period due to rerouting is minimized.
Clustering based Time Slot Assignment Protocol for Improving Performance in U...journal ijrtem
Recently, numerous approaches have been proposed for designing medium access control (MAC)
in underwater acoustic networks (UANs). Some of those works tried to adapt MAC protocols proposed for
terrestrial networks. However, unique environmental characteristics of UANs make the MAC protocols hard to be
used in the UANs and degrade network performance. In order to improve network performance, COD-TS MAC
protocol was proposed. COD-TS focuses on both single hop and multi-hop mode and utilizes CDMA for
exchanging schedule information between cluster heads. COD-TS has shortcomings such as collisions, additional
energy consumption by exchanging schedule information and near-far effect of CDMA. To overcome above
shortcomings, we propose a clustering-based time slot assignment protocol. In the proposed protocol, nodes are
clustered, and each cluster head performs two-hop neighbor cluster discovery operation. And then, a cluster head
obtains its own relative position information. Finally, the cluster head assigns its own time slot for data
transmission based on the information. Simulation results show that the proposed protocol has always better
performance compared to the COD-TS.
Performance Comparison of AODV, DSR and LAR1 in Mobile Ad-hoc Network based o...IOSR Journals
Abstract: In the last couple of years, the use of wireless networks has become more and more popular. A
MANET is a collection of self-organizing mobile nodes which is infrastructure less, autonomous, and standalone
networks. Each node in a MANET is free to move independently in any direction and will therefore change its
links to other devices frequently. Each must forward traffic unrelated to its own use and therefore be a router.
Simulation result has been obtained by a performance comparison of three routing protocols i.e. Ad hoc Ondemand
Distance Vector (AODV), Dynamic Source Routing (DSR), Location Aided Routing (LAR1) against
Simulation time. The Result is obtained using QualNet simulator version 6.1. Different protocols are evaluated
based on measures such as Average End to End delay (s), Average Jitter(s), and Packet delivery ratio.
Keywords: MANET, AODV, DSR, LAR1, QualNet 6.1
A cross layer delay-aware node disjoint multipath routing algorithm for mobil...ijwmn
Mobile Ad Hoc Networks (MANETS) require reliable routing and Quality of Service(QoS) mechanism to
support diverse applications with varying and stringent requirements for delay, jitter, bandwidth, packets
loss. Routing protocols such as AODV, AOMDV, DSR and OLSR use shortest path with minimum hop
count as the main metric for path selection, hence are not suitable for delay sensitive real time
applications. To support such applications delay constrained routing protocols are employed. These
Protocols makes path selection between source and destination based on the delay over the discovered
links during routing discovery and routing table calculations. We propose a variation of a node-disjoint
Multipath QoS Routing protocol called Cross Layer Delay aware Node Disjoint Multipath AODV (CLDMAODV)
based on delay constraint. It employs cross-layer communications between MAC and routing
layers to achieve link and channel-awareness. It regularly updates the path status in terms of lowest delay
incurred at each intermediate node. Performance of the proposed protocol is compared with single path
AODV and NDMR protocols. Proposed CLDM-AODV is superior in terms of better packet delivery and
reduced overhead between intermediate nodes.
LEACH is a hierarchical protocol in which most nodes transmit to cluster heads, and the cluster heads aggregate and compress the data and forward it to the base station (sink).In LEACH, a TDMA-based MAC protocol is integrated with clustering and a simple “routing” protocol. The goal of LEACH is to lower the energy consumption required to create and maintain clusters or to use the energy of the nodes in such a manner so as to improve the life time of a wireless sensor network. In this paper we are presenting an overview of the different protocol changes made in LEACH to improve network lifetime, throughput, coverage area of network etc.
LTE QOS DYNAMIC RESOURCE BLOCK ALLOCATION WITH POWER SOURCE LIMITATION AND QU...IJCNCJournal
3GPP has defined the long term evolution (LTE) for 3G radio access in order to maintain the future
competitiveness for 3G technology, the system provides the capability of supporting a mixture of services
with different quality of service (QoS) requirements. This paper proposes a new cross-layer scheduling
algorithm to satisfy better QoS parameters for real time applications. The proposed algorithm takes care of
allocating resource blocks (RBs) with different modulation and coding schemes (MCS) according to target
bit error rate (BER), user equipment supportable MCS, queue stability constraints and available transmit
power constraints. The proposed algorithm has been valued, compared with an earlier allocation algorithm
in terms of service rate and packet delay and showed better performance regards the real time
applications.
P ERFORMANCE C OMPARISON OF R OUTING P ROTOCOLS IN M OBILE A D H OC N E...ijujournal
Routing protocols have
an important
role in any
Mobile Ad Hoc Network
(MANET).
Researchers
have
elaborated several routing protocols that possess different performance levels
. In this
p
aper
we
give a
performance evaluation of
AODV,
DSR,
DSDV
, OLSR and DYMO
routing protocol
s
in
Mobile Ad Hoc
Networks
(MANETS)
to
determine
the best
in different scenarios
. We
analyse
these
MANET
routing
protocols by
using
NS
-
2 simulator
. We specify how
the
Number of No
d
es
parameter influences
their
performance. In this study
,
performance is
calculated
in terms
of Packet Delivery Ratio,
Average
End to
End Delay, Normalised Routing Load and Average Throughput
Performance comparison of routing protocols in mobile ad hoc networksijujournal
Routing protocols have an important role in any Mobile Ad Hoc Network (MANET). Researchers have elaborated several routing protocols that possess different performance levels. In this paper we give a performance evaluation of AODV, DSR, DSDV, OLSR and DYMO routing protocols in Mobile Ad Hoc
Networks (MANETS) to determine the best in different scenarios. We analyse these MANET routing protocols by using NS-2 simulator. We specify how the Number of Nodes parameter influences their performance. In this study, performance is calculated in terms of Packet Delivery Ratio, Average End to End Delay, Normalised Routing Load and Average Throughput.
Rate Adaptation for Time Varying Channels Using Distributed Relay Selectionpaperpublications3
Abstract: Fixed systems used in cooperative communication suffer from multiplexing loss and low spectral efficiency due to the half duplex constraint of relays. To improve the multiplexing gain, successive relaying is proposed. This allows concurrent transmission of the source and relays. However, the severe inter-relay interference becomes a key challenge. Here Rate Adaptation for Time Varying Channels Using Distributed Relay Selection is proposed, which is capable of adapting the relay’s rate using distributed relay selection.
Performance Analysis of Enhanced Opportunistic Minimum Cost Routingin Mobile ...IJERA Editor
Mobile Ad-Hoc Network (MANET) is a collection of wireless mobile nodes forming a temporary network with
infrastructure less environment to establish a data transmission between nodes within the network. A routing
protocol is used to discover routes between nodes. In this paper, we study the three existing routing protocols
namely AODV, DSDV and DSR to analyze theirperformance based on set of parameters.AODV and DSR
deliver almost all the packets compared to DSDV. Hence we try to modify the AODVprotocol and use in the
cooperative transmission.
In this paper, we study the cooperative transmission at the network layer and cooperative diversity at the
physical layer as a joint optimization of the transmission power in a Mobile Ad-Hoc Network (MANET) with
static channel. However due to variable wireless channels static routing is suboptimal. Proposed protocol
proactively selects forwarding nodes that work cooperatively forwarding the packet towards the destination.
Cooperative transmission side diversity helps in reducing interference. Diversity can be achieved at the physical
layer by coordinating the multiple nodes. Nodes are equipped with Omni-directional antenna and take the
advantages of transmission side diversity to achieve energy saving, under the assumption that channel gains are
available at the transmitters.
The proposed Opportunistic Minimum Cost Cooperative Transmission Shortest Path (OMCTSP) algorithms
select the best optimum route with minimum cost in terms of energy, number of hops, available bandwidth, link
quality (SNR) and outage probability. As the network becomes larger, finding optimal routes becomes
computationally intractable as the complexity of the dynamic programming (DP) approach increases as o (22n)
where n is the number of nodes in the networks. Hence we develop two suboptimal algorithms have complexity
of o (n2) perform as same as optimal algorithm. Also developthe Opportunistic Cooperative Routing in MANET
(O_CORMAN), which is a network layer opportunistic routing scheme for mobile ad hoc networks. Nodes in
the network use the components proactive routing protocol, forwarder list update and local re-transmission. We
evaluate the performance using NS 2.32 simulator there is significant performance improvement with respect to
energy, throughput packet delivery, and delay compared with Modified AODV (OMCTSP).
Design and implementation of low latency weighted round robin (ll wrr) schedu...ijwmn
Today’s wireless broadband networks are required to provide QoS guarantee as well as fairness to
different kinds of traffic. Recent wireless standards (such as LTE and WiMAX) have special provisions at
MAC layer for differentiating and scheduling data traffic for achieving QoS. The main focus of this paper is
concerned with high speed packet queuing/scheduling at central node such as base station (BS) or router to
handle network traffic. This paper proposes novel packet queuing scheme termed as Low Latency
Weighted Round Robin (LL-WRR) which is simple and effective amendment to weighted round robin (WRR)
for achieving low latency and improved fairness. Proposed LL-WRR queue scheduling scheme is
implemented in NS-2 considering IEEE 802.16 network [1] with real time video and Constant Bit Rate
(CBR) audio traffic connections. Simulation results show improvement obtained in latency and fairness
using LL-WRR. The proposed scheme introduces extra complexity of computing coefficient but its overall
impact is very small.
Modeling and Simulation of Wavelength-Routed optical Networksijceronline
All-optical Wavelength Division Multiplexing (WDM) networks providing extremely large bandwidths are among the most promising solutions to the increasing need for high-speed data transport. A lightpath has a specific route and one or more wavelengths through which the information is routed from the source to the destination node. In wavelength-routed optical networks, data are transmitted solely in the optical domain along lightpaths from source to destination without being converted into the electronic form and each lightpath is allowed to use the same wavelength on all the links along its path. This restriction is known as the wavelength continuity constraint. And it leads to an issue called as blocking in networks. Optical wavelength conversion with suitable Routing and wavelength assignment (RWA) can increase the performance and capacity of optical networks by eliminating this restriction and relaxing the wavelength continuity constraint. In this research, we analyze the problem of placing a limited number of wavelength converters in a mesh network using Weighted Maximum Segment Length (WMSL) converter placement algorithm. It employs Least-Loaded Routing and First-Fit (LLR-FF) RWA algorithm. It is tested on varying number of nodes in network and its respective blocking probabilities are calculated. The proposed algorithm provides the minimum blocking probability on optimal wavelength converters placement.
Single Mode Optical Fiber in Rof System Using DWDMIJERA Editor
Performance analysis was carried out to find the effect of crosstalk in a WDM system. Firstly, analysis of BER
was carried out without crosstalk. Then analysis of BER with crosstalk was done. Using equation for crosstalk,
number of channels was plotted using matlab. System parameters were optimized for a particular crosstalk.
Objective of the thesis work
Performance Analysis is carried out to find the effect of crosstalk due to optical cross connect in a DWDM
system considering a WDM based optical cross connect (OXC). An analysis is carried out to find the amount of
crosstalk due to OXC. The bit error rate performance degradation due to crosstalk is evaluated for OXC
parameter and number of wavelengths per fiber. The optimum parameters such as optimum number of channels
and hops are determined.
A Novel Timer-Based Hybrid Rerouting Algorithm for Improving Resource Utiliza...IJERA Editor
In this paper we investigate hybrid rerouting and minimization of incurred service disruption period due to
rerouting in Wavelength Division Multiplexed (WDM) transparent optical network. One limitation of such a
network is the wavelength continuity constraint which does not allow a circuit to be placed on a non
wavelength-continuous route. The impact of this constraint might have a severe consequence on the
performance of transparent optical networks especially in terms of rejection ratio ant it is especially severe when
traffic demands are unpredictable and characterized by random arrivals and departures. To alleviate the impact
of these constraints, either wavelength conversion or traffic rerouting can be used. Since, in the foreseeable
future, wavelength conversion is expected to remain an expensive technology, traffic rerouting is an attractive
alternative solution. Thus, we here propose to employ hybrid rerouting to improve the network performances.
Hybrid rerouting combines passive and active rerouting. Through simulation results, the performances of the
proposed algorithm in terms of rejection ratio are demonstrated to be promising while rerouting a small number
of already established lightpaths using Lightpath ReRouting (LRR). By rerouting a small number of existing
lightpaths using LRR, we hope that the incurred service disruption period due to rerouting is minimized.
MMINIMUM RESOURCE CONSUMPTIONS ROUTING FOR OPTICAL NETWORKSprj_publication
The problem of determining primary and backup paths for survivable optical WDM
networks is considered. Results of various available routing techniques that try to minimize
the combined cost of primary and the backup path are analyzed for the effects on network
parameters such as mean load, variance of the load on route, number of converters required
by the route and the length of the route. The route cost is modelled such a way that it is
extensible to include any new parameter and vary their relative importance. The efficiency of
such wavelength routed networks has been proved to improve for certain parameters, such as
reduction in blocking probability and number of converters required for desired performance.
The routing is enhanced to analyse effect on network parameters for all node full range
converters, limited number full converters, reserved primary and back up wavelengths and
with no such reservation.
Performance Analysis of Enhanced Opportunistic Minimum Cost Routingin Mobile ...IJERA Editor
Mobile Ad-Hoc Network (MANET) is a collection of wireless mobile nodes forming a temporary network with
infrastructure less environment to establish a data transmission between nodes within the network. A routing
protocol is used to discover routes between nodes. In this paper, we study the three existing routing protocols
namely AODV, DSDV and DSR to analyze theirperformance based on set of parameters.AODV and DSR
deliver almost all the packets compared to DSDV. Hence we try to modify the AODVprotocol and use in the
cooperative transmission.
In this paper, we study the cooperative transmission at the network layer and cooperative diversity at the
physical layer as a joint optimization of the transmission power in a Mobile Ad-Hoc Network (MANET) with
static channel. However due to variable wireless channels static routing is suboptimal. Proposed protocol
proactively selects forwarding nodes that work cooperatively forwarding the packet towards the destination.
Cooperative transmission side diversity helps in reducing interference. Diversity can be achieved at the physical
layer by coordinating the multiple nodes. Nodes are equipped with Omni-directional antenna and take the
advantages of transmission side diversity to achieve energy saving, under the assumption that channel gains are
available at the transmitters.
The proposed Opportunistic Minimum Cost Cooperative Transmission Shortest Path (OMCTSP) algorithms
select the best optimum route with minimum cost in terms of energy, number of hops, available bandwidth, link
quality (SNR) and outage probability. As the network becomes larger, finding optimal routes becomes
computationally intractable as the complexity of the dynamic programming (DP) approach increases as o (2
2n)
where n is the number of nodes in the networks. Hence we develop two suboptimal algorithms have complexity
of o (n2) perform as same as optimal algorithm. Also developthe Opportunistic Cooperative Routing in MANET
(O_CORMAN), which is a network layer opportunistic routing scheme for mobile ad hoc networks. Nodes in
the network use the components proactive routing protocol, forwarder list update and local re-transmission. We
evaluate the performance using NS 2.32 simulator there is significant performance improvement with respect to
energy, throughput packet delivery, and delay compared with Modified AODV (OMCTSP).
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
A New Analysis for Wavelength Translation in Regular WDM NetworksVishal Sharma, Ph.D.
We present a new analysis of wavelength translation in
regular, all-optical WDM networks, that is simple, computationally
inexpensive, and accurate for both low and high
network loads. In a network with
k
wavelengths per link,
we model the output link by an auxiliary
M/M/k/k
queueing
system. We then obtain a closed-form expression for
the probability
P succ
that a session arriving at a node at a
random time successfully establishes a connection from its
source node to its destination node. Unlike previous analyses,
which use the link independence blocking assumption,
we account for the dependence between the acquisition of
wavelengths on successive links of the session’s path. Based
on the success probability, we show that the throughput per
wavelength increases superlinearly (as expected) as we increase
the number of wavelengths per link; however, the
extent of this superlinear increase in throughput saturates
rather quickly. This suggests some interesting possibilities
for network provisioning in an all-optical network. We verify the accuracy of our analysis via simulations for the torus
and hypercube networks.
Energy Efficient Multipath Routing For Mobile Ad Hoc NetworksZac Darcy
Energy consumption is a significant issue in ad hoc networks since mobile nodes are battery powered. In
order to prolong the lifetime of ad hoc networks, it is the most critical issue to minimize the energy
consumption of nodes. In this paper, we propose an energy efficient multipath routing protocol for
choosing energy efficient path. This system also considers transmission power of nodes and residual energy
as energy metrics in order to maximize the network lifetime and to reduce energy consumption of mobile
nodes. The objective of our proposed system is to find an optimal route based on two energy metrics while
choosing a route to transfer data packets. This system is implemented by using NS-2.34. Simulation results
show that the proposed routing protocol with transmission power and residual energy control mode can
extend the life-span of network and can achieve higher performance when compared to traditional ad-hoc
on-demand multipath distance vector (AOMDV) routing protocol.
Energy Efficient Multipath Routing For Mobile Ad Hoc NetworksZac Darcy
Energy consumption is a significant issue in ad hoc networks since mobile nodes are battery powered. In
order to prolong the lifetime of ad hoc networks, it is the most critical issue to minimize the energy
consumption of nodes. In this paper, we propose an energy efficient multipath routing protocol for
choosing energy efficient path. This system also considers transmission power of nodes and residual energy
as energy metrics in order to maximize the network lifetime and to reduce energy consumption of mobile
nodes. The objective of our proposed system is to find an optimal route based on two energy metrics while
choosing a route to transfer data packets. This system is implemented by using NS-2.34. Simulation results
show that the proposed routing protocol with transmission power and residual energy control mode can
extend the life-span of network and can achieve higher performance when compared to traditional ad-hoc
on-demand multipath distance vector (AOMDV) routing protocol.
AN MINIMUM RECONFIGURATION PROBABILITY ROUTING ALGORITHM FOR RWA IN ALL-OPTIC...sipij
In this paper, we present a detailed study of Minimum Reconfiguration Probability Routing (MRPR) algorithm, and its performance evaluation in comparison with Adaptive unconstrained routing (AUR) and Least Loaded routing (LLR) algorithms. We have minimized the effects of failures on link and router failure in the network under changing load conditions, we assess the probability of service and number of light path failures due to link or route failure on Wavelength Interchange(WI) network. The computation complexity is reduced by using Kalman Filter(KF) techniques. The minimum reconfiguration probability
routing (MRPR) algorithm selects most reliable routes and assign wavelengths to connections in a manner that utilizes the light path(LP) established efficiently considering all possible requests.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
MPC-EAR : Maximal Power Conserved And Energy Aware Routing in Ad hoc Networksijsrd.com
Power preservation in wireless ad hoc networks is a decisive factor as energy resources are inadequate at the electronic devices in use. Power-aware routing strategies are fundamentally route selection strategies built on accessible ad hoc routing protocols. This paper proposed a new Maximal Power Conserved And Energy Aware Routing (MPC-EAR ) topology for mobile ad hoc networks that enhances the network life span. Simulation results prove that the projected protocol has a higher performance other minimal energy usage, energy level aware and energy conserving routing protocols such as MTPR, MMECR and CMMECR.
DYNAMIC CONGESTION CONTROL IN WDM OPTICAL NETWORKcscpconf
This paper is based on Wavelength Division Multiplexing (WDM) optical networking. In this optical networking, prior to data transfer, lightpath establishment between source and
destination nodes is usually carried out through a wavelength reservation protocol. This wavelength is reserved corresponding to a route between the source and destination and the
route is chosen following any standard routing protocol based on shortest path. The backward reservation protocol is implemented initially. A fixed connected and weighted network is
considered. The inputs of this implementation are the fixed network itself and its corresponding shortest path matrix. After this initial level of implementation, the average node usage over a time period is calculated and various thresholds for node usage are considered. Above threshold value, request arriving at that path selects its next shortest path. This concept is
implemented on various wavelengths. The output represents the performance issues of dynamic congestion control.
Vehicle Ad Hoc Networks (VANETs) have become a viable technology to improve traffic flow and safety on the roads. Due to its effectiveness and scalability, the Wingsuit Search-based Optimised Link State Routing Protocol (WS-OLSR) is frequently used for data distribution in VANETs. However, the selection of MultiPoint Relays (MPRs) plays a pivotal role in WS-OLSR's performance. This paper presents an improved MPR selection algorithm tailored to WS-OLSR, designed to enhance the overall routing efficiency and reduce overhead. The analysis found that the current OLSR protocol has problems such as redundancy of HELLO and TC message packets or failure to update routing information in time, so a WS-OLSR routing protocol based on improved-MPR selection algorithm was proposed. Firstly, factors such as node mobility and link changes are comprehensively considered to reflect network topology changes, and the broadcast cycle of node HELLO messages is controlled through topology changes. Secondly, a new MPR selection algorithm is proposed, considering link stability issues and nodes. Finally, evaluate its effectiveness in terms of packet delivery ratio, end-to-end delay, and control message overhead. Simulation results demonstrate the superior performance of our improved MR selection algorithm when compared to traditional approaches.
A Novel Medium Access Control Strategy for Heterogeneous Traffic in Wireless ...IJCNCJournal
So far, Wireless Body Area Networks (WBANs) have played a pivotal role in driving the development of intelligent healthcare systems with broad applicability across various domains. Each WBAN consists of one or more types of sensors that can be embedded in clothing, attached directly to the body, or even implanted beneath an individual's skin. These sensors typically serve asingle application. However, the traffic generated by each sensor may have distinct requirements. This diversity necessitates a dual approach: tailored treatment based on the specific needs of each traffic typeand the fulfillment of application requirements, such asreliability and timeliness. Never the less, the presence of energy constraints and the unreliable nature of wireless communications make QoS provisioning under such networks a non-trivial task. In this context, the current paper introduces a novel Medium AccessControl (MAC) strategy for the regular traffic applications of WBANs, designed to significantly enhance efficiency when compared to the established MAC protocols IEEE 802.15.4 and IEEE 802.15.6, with a particular focus on improving reliability, timeliness, and energy efficiency.
May_2024 Top 10 Read Articles in Computer Networks & Communications.pdfIJCNCJournal
The International Journal of Computer Networks & Communications (IJCNC) is a bi monthly open access peer-reviewed journal that publishes articles which contribute new results in all areas of Computer Networks & Communications. The journal focuses on all technical and practical aspects of Computer Networks & data Communications. The goal of this journal is to bring together researchers and practitioners from academia and industry to focus on advanced networking concepts and establishing new collaborations in these areas.
A Topology Control Algorithm Taking into Account Energy and Quality of Transm...IJCNCJournal
The efficient use of energy in wireless sensor networks is critical for extending node lifetime. The network topology is one of the factors that have a significant impact on the energy usage at the nodes and the quality of transmission (QoT) in the network. We propose a topology control algorithm for software-defined wireless sensor networks (SDWSNs) in this paper. Our method is to formulate topology control algorithm as a nonlinear programming (NP) problem with the objective to optimizing two metrics, maximum communication range, and desired degree. This NP problem is solved at the SDWSN controller by employing the genetic algorithm (GA) to determine the best topology. The simulation results show that the proposed algorithm outperforms the MaxPower algorithm in terms of average node degree and energy expansion ratio.
Multi-Server user Authentication Scheme for Privacy Preservation with Fuzzy C...IJCNCJournal
The integration of artificial intelligence technology with a scalable Internet of Things (IoT) platform facilitates diverse smart communication services, allowing remote users to access services from anywhere at any time. The multi-server environment within IoT introduces a flexible security service model, enabling users to interact with any server through a single registration. To ensure secure and privacy preservation services for resources, an authentication scheme is essential. Zhao et al. recently introduced a user authentication scheme for the multi-server environment, utilizing passwords and smart cards, claiming resilience against well-known attacks. This paper conducts cryptanalysis on Zhao et al.'s scheme, focusing on denial of service and privacy attacks, revealing a lack of user-friendliness. Subsequently, we propose a new multi-server user authentication scheme for privacy preservation with fuzzy commitment over the IoT environment, addressing the shortcomings of Zhao et al.'s scheme. Formal security verification of the proposed scheme is conducted using the ProVerif simulation tool. Through both formal and informal security analyses, we demonstrate that the proposed scheme is resilient against various known attacks and those identified in Zhao et al.'s scheme.
Advanced Privacy Scheme to Improve Road Safety in Smart Transportation SystemsIJCNCJournal
In -Vehicle Ad-Hoc Network (VANET), vehicles continuously transmit and receive spatiotemporal data with neighboring vehicles, thereby establishing a comprehensive 360-degree traffic awareness system. Vehicular Network safety applications facilitate the transmission of messages between vehicles that are near each other, at regular intervals, enhancing drivers' contextual understanding of the driving environment and significantly improving traffic safety. Privacy schemes in VANETs are vital to safeguard vehicles’ identities and their associated owners or drivers. Privacy schemes prevent unauthorized parties from linking the vehicle's communications to a specific real-world identity by employing techniques such as pseudonyms, randomization, or cryptographic protocols. Nevertheless, these communications frequently contain important vehicle information that malevolent groups could use to Monitor the vehicle over a long period. The acquisition of this shared data has the potential to facilitate the reconstruction of vehicle trajectories, thereby posing a potential risk to the privacy of the driver. Addressing the critical challenge of developing effective and scalable privacy-preserving protocols for communication in vehicle networks is of the highest priority. These protocols aim to reduce the transmission of confidential data while ensuring the required level of communication. This paper aims to propose an Advanced Privacy Vehicle Scheme (APV) that periodically changes pseudonyms to protect vehicle identities and improve privacy. The APV scheme utilizes a concept called the silent period, which involves changing the pseudonym of a vehicle periodically based on the tracking of neighboring vehicles. The pseudonym is a temporary identifier that vehicles use to communicate with each other in a VANET. By changing the pseudonym regularly, the APV scheme makes it difficult for unauthorized entities to link a vehicle's communications to its real-world identity. The proposed APV is compared to the SLOW, RSP, CAPS, and CPN techniques. The data indicates that the efficiency of APV is a better improvement in privacy metrics. It is evident that the AVP offers enhanced safety for vehicles during transportation in the smart city.
April 2024 - Top 10 Read Articles in Computer Networks & CommunicationsIJCNCJournal
The International Journal of Computer Networks & Communications (IJCNC) is a bi monthly open access peer-reviewed journal that publishes articles which contribute new results in all areas of Computer Networks & Communications. The journal focuses on all technical and practical aspects of Computer Networks & data Communications. The goal of this journal is to bring together researchers and practitioners from academia and industry to focus on advanced networking concepts and establishing new collaborations in these areas.
DEF: Deep Ensemble Neural Network Classifier for Android Malware DetectionIJCNCJournal
Malware is one of the threats to security of computer networks and information systems. Since malware instances are available sufficiently, there is increased interest among researchers on usage of Artificial Intelligence (AI). Of late AI-enabled methods such as machine learning (ML) and deep learning paved way for solving many real-world problems. As it is a learning-based approach, accumulated training samples help in improving thequality of training and thus leveraging malware detection accuracy. Existing deep learning methods are focusing on learning-based malware detection systems. However, there is need for improving the state of the art through ensemble approach. Towards this end, in this paper we proposed a framework known as Deep Ensemble Framework (DEF) for automatic malware detection. The framework obtains features from training samples. From given malware instance a grayscale image is generated. There is another process to extract the opcode sequences. Convolutional Neural Network (CNN) and Long Short Term Memory (LSTM) techniques are used to obtain grayscale image and opcode sequence respectively. Afterwards, a stacking ensemble is employed in order to achieve efficient malware detection and classification. Malware samples collected fromthe Internet sources and Microsoft are used for theempirical study. An algorithm known as Ensemble Learning for Automatic Malware Detection (EL-AML) is proposed to realize our framework. Another algorithm named Pre-Process is proposed to assist the EL-AML algorithm for obtaining intermediate features required by CNN and LSTM.Empirical study reveals that our framework outperforms many existing methods in terms of speed-up and accuracy.
High Performance NMF Based Intrusion Detection System for Big Data IOT TrafficIJCNCJournal
With the emergence of smart devices and the Internet of Things (IoT), millions of users connected to the network produce massive network traffic datasets. These vast datasets of network traffic, Big Data are challenging to store, deal with and analyse using a single computer. In this paper we developed parallel implementation using a High Performance Computer (HPC) for the Non-Negative Matrix Factorization technique as an engine for an Intrusion Detection System (HPC-NMF-IDS). The large IoT traffic datasets of order of millions samples are distributed evenly on all the computing cores for both storage and speedup purpose. The distribution of computing tasks involved in the Matrix Factorization takes into account the reduction of the communication cost between the computing cores. The experiments we conducted on the proposed HPC-IDS-NMF give better results than the traditional ML-based intrusion detection systems. We could train the HPC model with datasets of one million samples in only 31 seconds instead of the 40 minutes using one processor), that is a speed up of 87 times. Moreover, we have got an excellent detection accuracy rate of 98% for KDD dataset.
A Novel Medium Access Control Strategy for Heterogeneous Traffic in Wireless ...IJCNCJournal
So far, Wireless Body Area Networks (WBANs) have played a pivotal role in driving the development of intelligent healthcare systems with broad applicability across various domains. Each WBAN consists of one or more types of sensors that can be embedded in clothing, attached directly to the body, or even implanted beneath an individual's skin. These sensors typically serve asingle application. However, the traffic generated by each sensor may have distinct requirements. This diversity necessitates a dual approach: tailored treatment based on the specific needs of each traffic typeand the fulfillment of application requirements, such asreliability and timeliness. Never the less, the presence of energy constraints and the unreliable nature of wireless communications make QoS provisioning under such networks a non-trivial task. In this context, the current paper introduces a novel Medium AccessControl (MAC) strategy for the regular traffic applications of WBANs, designed to significantly enhance efficiency when compared to the established MAC protocols IEEE 802.15.4 and IEEE 802.15.6, with a particular focus on improving reliability, timeliness, and energy efficiency.
A Topology Control Algorithm Taking into Account Energy and Quality of Transm...IJCNCJournal
The efficient use of energy in wireless sensor networks is critical for extending node lifetime. The network topology is one of the factors that have a significant impact on the energy usage at the nodes and the quality of transmission (QoT) in the network. We propose a topology control algorithm for software-defined wireless sensor networks (SDWSNs) in this paper. Our method is to formulate topology control algorithm as a nonlinear programming (NP) problem with the objective to optimizing two metrics, maximum communication range, and desired degree. This NP problem is solved at the SDWSN controller by employing the genetic algorithm (GA) to determine the best topology. The simulation results show that the proposed algorithm outperforms the MaxPower algorithm in terms of average node degree and energy expansion ratio.
Multi-Server user Authentication Scheme for Privacy Preservation with Fuzzy C...IJCNCJournal
The integration of artificial intelligence technology with a scalable Internet of Things (IoT) platform facilitates diverse smart communication services, allowing remote users to access services from anywhere at any time. The multi-server environment within IoT introduces a flexible security service model, enabling users to interact with any server through a single registration. To ensure secure and privacy preservation services for resources, an authentication scheme is essential. Zhao et al. recently introduced a user authentication scheme for the multi-server environment, utilizing passwords and smart cards, claiming resilience against well-known attacks. This paper conducts cryptanalysis on Zhao et al.'s scheme, focusing on denial of service and privacy attacks, revealing a lack of user-friendliness. Subsequently, we propose a new multi-server user authentication scheme for privacy preservation with fuzzy commitment over the IoT environment, addressing the shortcomings of Zhao et al.'s scheme. Formal security verification of the proposed scheme is conducted using the ProVerif simulation tool. Through both formal and informal security analyses, we demonstrate that the proposed scheme is resilient against various known attacks and those identified in Zhao et al.'s scheme.
Advanced Privacy Scheme to Improve Road Safety in Smart Transportation SystemsIJCNCJournal
In -Vehicle Ad-Hoc Network (VANET), vehicles continuously transmit and receive spatiotemporal data with neighboring vehicles, thereby establishing a comprehensive 360-degree traffic awareness system. Vehicular Network safety applications facilitate the transmission of messages between vehicles that are near each other, at regular intervals, enhancing drivers' contextual understanding of the driving environment and significantly improving traffic safety. Privacy schemes in VANETs are vital to safeguard vehicles’ identities and their associated owners or drivers. Privacy schemes prevent unauthorized parties from linking the vehicle's communications to a specific real-world identity by employing techniques such as pseudonyms, randomization, or cryptographic protocols. Nevertheless, these communications frequently contain important vehicle information that malevolent groups could use to Monitor the vehicle over a long period. The acquisition of this shared data has the potential to facilitate the reconstruction of vehicle trajectories, thereby posing a potential risk to the privacy of the driver. Addressing the critical challenge of developing effective and scalable privacy-preserving protocols for communication in vehicle networks is of the highest priority. These protocols aim to reduce the transmission of confidential data while ensuring the required level of communication. This paper aims to propose an Advanced Privacy Vehicle Scheme (APV) that periodically changes pseudonyms to protect vehicle identities and improve privacy. The APV scheme utilizes a concept called the silent period, which involves changing the pseudonym of a vehicle periodically based on the tracking of neighboring vehicles. The pseudonym is a temporary identifier that vehicles use to communicate with each other in a VANET. By changing the pseudonym regularly, the APV scheme makes it difficult for unauthorized entities to link a vehicle's communications to its real-world identity. The proposed APV is compared to the SLOW, RSP, CAPS, and CPN techniques. The data indicates that the efficiency of APV is a better improvement in privacy metrics. It is evident that the AVP offers enhanced safety for vehicles during transportation in the smart city.
DEF: Deep Ensemble Neural Network Classifier for Android Malware DetectionIJCNCJournal
Malware is one of the threats to security of computer networks and information systems. Since malware instances are available sufficiently, there is increased interest among researchers on usage of Artificial Intelligence (AI). Of late AI-enabled methods such as machine learning (ML) and deep learning paved way for solving many real-world problems. As it is a learning-based approach, accumulated training samples help in improving thequality of training and thus leveraging malware detection accuracy. Existing deep learning methods are focusing on learning-based malware detection systems. However, there is need for improving the state of the art through ensemble approach. Towards this end, in this paper we proposed a framework known as Deep Ensemble Framework (DEF) for automatic malware detection. The framework obtains features from training samples. From given malware instance a grayscale image is generated. There is another process to extract the opcode sequences. Convolutional Neural Network (CNN) and Long Short Term Memory (LSTM) techniques are used to obtain grayscale image and opcode sequence respectively. Afterwards, a stacking ensemble is employed in order to achieve efficient malware detection and classification. Malware samples collected fromthe Internet sources and Microsoft are used for theempirical study. An algorithm known as Ensemble Learning for Automatic Malware Detection (EL-AML) is proposed to realize our framework. Another algorithm named Pre-Process is proposed to assist the EL-AML algorithm for obtaining intermediate features required by CNN and LSTM.Empirical study reveals that our framework outperforms many existing methods in terms of speed-up and accuracy.
High Performance NMF based Intrusion Detection System for Big Data IoT TrafficIJCNCJournal
With the emergence of smart devices and the Internet of Things (IoT), millions of users connected to the network produce massive network traffic datasets. These vast datasets of network traffic, Big Data are challenging to store, deal with and analyse using a single computer. In this paper we developed parallel implementation using a High Performance Computer (HPC) for the Non-Negative Matrix Factorization technique as an engine for an Intrusion Detection System (HPC-NMF-IDS). The large IoT traffic datasets of order of millions samples are distributed evenly on all the computing cores for both storage and speedup purpose. The distribution of computing tasks involved in the Matrix Factorization takes into account the reduction of the communication cost between the computing cores. The experiments we conducted on the proposed HPC-IDS-NMF give better results than the traditional ML-based intrusion detection systems. We could train the HPC model with datasets of one million samples in only 31 seconds instead of the 40 minutes using one processor), that is a speed up of 87 times. Moreover, we have got an excellent detection accuracy rate of 98% for KDD dataset.
IoT Guardian: A Novel Feature Discovery and Cooperative Game Theory Empowered...IJCNCJournal
Cyber intrusion attacks increasingly target the Internet of Things (IoT) ecosystem, exploiting vulnerable devices and networks. Malicious activities must be identified early to minimize damage and mitigate threats. Using actual benign and attack traffic from the CICIoT2023 dataset, this WORK aims to evaluate and benchmark machine-learning techniques for IoT intrusion detection. There are four main phases to the system. First, the CICIoT2023 dataset is refined to remove irrelevant features and clean up missing and duplicate data. The second phase employs statistical models and artificial intelligence to discover novel features. The most significant features are then selected in the third phase based on cooperative game theory. Using the original CICIoT2023 dataset and a dataset containing only novel features, we train and evaluate a variety of machine learning classifiers. On the original dataset, Random Forest achieved the highest accuracy of 99%. Still, with novel features, Random Forest's performance dropped only slightly (96%) while other models achieved significantly lower accuracy. As a whole, the work contributes substantial contributions to tailored feature engineering, feature selection, and rigorous benchmarking of IoT intrusion detection techniques. IoT networks and devices face continuously evolving threats, making it necessary to develop robust intrusion detection systems.
Enhancing Traffic Routing Inside a Network through IoT Technology & Network C...IJCNCJournal
IoT networking uses real items as stationary or mobile nodes. Mobile nodes complicate networking. Internet of Things (IoT) networks have a lot of control overhead messages because devices are mobile. These signals are generated by the constant flow of control data as such device identity, geographical positioning, node mobility, device configuration, and others. Network clustering is a popular overhead communication management method. Many cluster-based routing methods have been developed to address system restrictions. Node clustering based on the Internet of Things (IoT) protocol, may be used to cluster all network nodes according to predefined criteria. Each cluster will have a Smart Designated Node. SDN cluster management is efficient. Many intelligent nodes remain in the network. The network design spreads these signals. This paper presents an intelligent and responsive routing approach for clustered nodes in IoT networks. An existing method builds a new sub-area clustered topology. The Nodes Clustering Based on the Internet of Things (NCIoT) method improves message transmission between any two nodes. This will facilitate the secure and reliable interchange of healthcare data between professionals and patients. NCIoT is a system that organizes nodes in the Internet of Things (IoT) by grouping them together based on their proximity. It also picks SDN routes for these nodes. This approach involves selecting one option from a range of choices and preparing for likely outcomes problem addressing limitations on activities is a primary focus during the review process. Predictive inquiry employs the process of analyzing data to forecast and anticipate future events. This document provides an explanation of compact units. The Predictive Inquiry Small Packets (PISP) improved its backup system and partnered with SDN to establish a routing information table for each intelligent node, resulting in higher routing performance. Both principal and secondary roads are available for use. The simulation findings indicate that NCIoT algorithms outperform CBR protocols. Enhancements lead to a substantial 78% boost in network performance. In addition, the end-to-end latency dropped by 12.5%. The PISP methodology produces 5.9% more inquiry packets compared to alternative approaches. The algorithms are constructed and evaluated against academic ones.
IoT Guardian: A Novel Feature Discovery and Cooperative Game Theory Empowered...IJCNCJournal
Cyber intrusion attacks increasingly target the Internet of Things (IoT) ecosystem, exploiting vulnerable devices and networks. Malicious activities must be identified early to minimize damage and mitigate threats. Using actual benign and attack traffic from the CICIoT2023 dataset, this WORK aims to evaluate and benchmark machine-learning techniques for IoT intrusion detection. There are four main phases to the system. First, the CICIoT2023 dataset is refined to remove irrelevant features and clean up missing and duplicate data. The second phase employs statistical models and artificial intelligence to discover novel features. The most significant features are then selected in the third phase based on cooperative game theory. Using the original CICIoT2023 dataset and a dataset containing only novel features, we train and evaluate a variety of machine learning classifiers. On the original dataset, Random Forest achieved the highest accuracy of 99%. Still, with novel features, Random Forest's performance dropped only slightly (96%) while other models achieved significantly lower accuracy. As a whole, the work contributes substantial contributions to tailored feature engineering, feature selection, and rigorous benchmarking of IoT intrusion detection techniques. IoT networks and devices face continuously evolving threats, making it necessary to develop robust intrusion detection systems.
** Connect, Collaborate, And Innovate: IJCNC - Where Networking Futures Take ...IJCNCJournal
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Length: 30 minutes
Session Overview
-------------------------------------------
During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
- Which features are provided by Grafana?
- Demonstration of InfluxDB and Grafana using a practice web application
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https://www.rttsweb.com/jmeter-integration-webinar
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The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
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Speakers:
Bob Boule
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Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
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Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Neuro-symbolic is not enough, we need neuro-*semantic*
A Wavelength and Converter Assignment Scheme Using Converter Usage History in Wavelength-Routed Networks
1. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
DOI : 10.5121/ijcnc.2013.5406 63
A Wavelength and Converter Assignment
Scheme Using Converter Usage History
in Wavelength-Routed Networks
Yukinobu Fukushima, Takahiro Ooishi and Tokumi Yokohira
The Graduate School of Natural Science and Technology, Okayama University,
3-1-1 Tsushima-naka, Kita-ku, Okayama-city, 700-8530 Japan
fukusima@okayama-u.ac.jp
ABSTRACT
In wavelength-routed networks, wavelength conversion improves lightpath blocking probability by
eliminating the wavelength-continuity constraint. Because wavelength converters remain expensive in the
near future, we need a wavelength and converter assignment scheme that decreases blocking probability
with a limited number of converters. In this paper, we propose a wavelength and converter assignment
scheme for decreasing blocking probability. Our scheme avoids contention among multiple lightpath
requests by making each node-pair to perform wavelength conversion at different intermediate nodes with
more idle converters. Simulation results show that 1) our scheme decreases blocking probability by about
between 44% and 83% and 2) our scheme needs one or two fewer wavelength converters per node to
achieve near-optimal blocking probability compared with conventional schemes.
KEYWORDS
WDM, Wavelength and converter assignment problem, Wavelength conversion
1. INTRODUCTION
With the population of video streaming [1], [2] on the Internet, there is an increasing need for
bandwidth. Wavelength-Division Multiplexing (WDM) provides huge bandwidth by allowing
simultaneous data transmission on multiplexed wavelengths on a single fiber. Among several
network architectures for WDM network, wavelength-routed network is believed to be the most
promising architecture [3]–[6]. In wavelength-routed networks, access networks communicate
with each other via all-optical connections called lightpaths.
Performance of wavelength-routed network (i.e., blocking probability of lightpaths) depends on
routing and wavelength assignment (RWA) algorithm, which determines a route and an assigned
wavelength of each lightpath. RWA can be performed either in a centralized or distributed
manner. Because centralized network control can not cope with the rapid growth of WDM
networks because of the lack of scalability, distributed network control is more suitable [7]–[9].
In conventional research for RWA, RWA is divided into a routing sub-problem and a wavelength
assignment sub-problem because RWA is time-consuming [10]. This paper focuses on a
wavelength-assignment sub-problem.
Wavelength conversion improves lightpath blocking probability by eliminating the wavelength
continuity constraint (i.e., the constraint that the same wavelength must be assigned to a lightpath
on links along a route) [11]–[14]. However, because wavelength converter cost remains expensive
in the near future, the number of wavelength converters deployed in the network is limited.
2. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
64
Therefore, we need to realize as low blocking probability as possible with limited number of
wavelength converters.
Most of the conventional wavelength-assignment algorithms (e.g., First-Fit (FF), Most-Used
(MU) and Least-Used (LU)) only perform wavelength assignment and do not consider converter
assignment. As a result, they tend to assign more converters than needed in order to establish a
lightpath, and consequently, the more forthcoming lightpaths are blocked because of wavelength
continuity constraint. Some conventional algorithms (First-Longest lambda-Run (FLR) [15] and
LEast Converter first (LEC) [16]) consider both wavelength and converter assignment. They try
to decrease lightpath blocking probability by minimizing the number of converters assigned to a
lightpath. However, in order to decrease blocking probability, it is more important to avoid
multiple node-pairs from reserving the same wavelength converter at the same time.
In this paper, we propose a wavelength and converter assignment scheme for decreasing blocking
probability. Our scheme avoids contention of lightpath requests among multiple node-pairs by
making each node-pair to perform wavelength conversion at different intermediate nodes. Each
node-pair can realize this by selecting its preferred converter based on statistical information
learned from wavelength converter usage history. In addition, our proposed scheme tries to
perform wavelength conversion at intermediate nodes with more idle converters in order to keep
as many wavelength conversion nodes as possible available. Key idea behind our scheme is based
on Priority-based Wavelength Assignment (PWA) [17], which only considers wavelength
assignment in optical burst switching (OBS) networks [18]. The PWA avoids multiple node-pairs
from reserving the same wavelength using statistical information learned from wavelength
priority database.
The paper is organized as follows. In section 2, we present the network architecture and
routing/signaling protocol that we adopt, and we explain the conventional wavelength and
converter assignment schemes. We propose our scheme using converter usage history in section 3.
Then, we show our evaluation results in section 4. Section 5 concludes this paper.
2. WAVELENGTH AND CONVERTER ASSIGNMENT IN WAVELENGTH-
ROUTED NETWORKS
2.1. Network Architecture
Figure 1 depicts architecture of wavelength-routed networks. It consists of edge/core wavelength
routing nodes interconnected by fibers. Wavelength routing nodes exchange link state information
with a routing protocol such as OSPF-TE [19] in order to obtain network topology and resource
usage information of each link. When an access network communicates with other access network,
it first determines a route of a lightpath based on topology and resource usage information. Then,
it sets up the lightpath with a signaling protocol such as RSVP-TE [20]. We assume that the
destination-initiated reservation (DIR) [21] is adopted for resource reservation method. In the
DIR, lightpath request message from source to destination only collects link state information
along the route. Then, the destination node selects an appropriate wavelength and converter, and
sends a reservation request to reserve the wavelength along the route.
Figure 2 shows a node architecture that we assume in this research. It consists of demultiplexers
(DEMUX), Optical Cross–Connects (OXC), multiplexers (MUX) and wavelength converters
(WC). When a node relays a wavelength for establishment of a lightpath, a DEMUX first
demultiplexes an input signal into each wavelength. Then, an OXC switches each wavelength to
3. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
65
an appropriate output port. Finally a MUX multiplexes wavelengths into an output signal. When
the wavelength same as an input wavelength is not idle on an output fiber, the input wavelength
Core node
Edge node
Fiber
Wavelength-routed network
Access network
Lightpath
Figure 1. Wavelength-routed network
OXC
Input fiber
WC
Output fiber
DEMUX MUX
WC
Wavelength routing node
ᕇ1
ᕇ2
ᕇ3
ᕇ4
ᕇ1
ᕇ2
ᕇ3
ᕇ4
ᕇ1
ᕇ2
ᕇ3
ᕇ4
ᕇ1
ᕇ2
ᕇ3
ᕇ4
Figure 2. Node architecture
is switched to a wavelength converter and converted to another wavelength idle on an output fiber.
We assume that wavelength converters are deployed on nodes in a trunk–type basis [22]. In the
trunk–type, wavelength converters are shared among input ports. The input port that actually
needs wavelength conversion is switched to an output port with a full wavelength converter. As a
result, the number of wavelength converters deployed is reduced.
2.2. Wavelength and Converter Assignment Problem
The wavelength and converter assignment problem that we tackle in this paper is expressed as
follows: given 1) a route of a requested lightpath and 2) link-state information of links on the
route, determine wavelengths and converters assigned to the lightpath so that the total blocking
probability is minimized.
4. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
66
2.3. Conventional Wavelength and Converter Assignment Schemes
2.3.1 FLR (First Longest-Lambda Run)
The FLR [15] tries to decrease blocking probability by minimizing the number of converters
assigned to a lightpath. The FLR uses the concept of lambda-run. A lambda-run is a sequence of
the same wavelengths that are idle on successive links along a route. In addition, a lambda-run
satisfies the following conditions: 1) originating from the source node of a lightpath or an
intermediate node with at least one idle converter, 2) terminating at the destination node of a
lightpath or an intermediate node with at least one idle converter, and 3) being as long as possible.
The FLR repeatedly selects the longest lambda-run from the source node to the destination node.
At the terminal of each lambda-run, it performs wavelength conversion. If a set of lambda-runs
from the source to the destination is found, the lightpath is successfully set up, otherwise, blocked.
In [15], it is proven that this simple policy leads to minimizing the number of wavelength
conversions in setting up a lightpath.
2.3.2 LEC (LEast Converter first)
The LEC [16] tries to decrease blocking probability by minimizing the number of converters
assigned to a lightpath as well as the FLR. The LEC uses an auxiliary graph that represents
wavelength and converter usage information on a route of a lightpath.
When the LEC sets up a lightpath, it first constructs an auxiliary graph based on link-state
information on the route. Then, the LEC assigns a constant cost f to an edge corresponding to an
idle wavelength on a link, an infinity cost to an edge corresponding to an used wavelength on a
link, and a constant cost g to an edge corresponding to performing wavelength conversion on an
intermediate node. Note that wavelength conversion cost g is larger than cost of any path without
wavelength conversion (i.e., g > nf, where n is the hop count of the route). After that, the LEC
computes the minimum cost path from source to destination with Dijkstra algorithm on the graph.
If such a path is obtained, LEC reserves the selected wavelengths and converters and successfully
sets up a lightpath. Otherwise, the LEC refuses the request.
3. WAVELENGTH AND CONVERTER ASSIGNMENT SCHEME USING
CONVERTER USAGE HISTORY
We propose a wavelength and converter assignment scheme that tries to decrease lightpath
blocking probability. Our scheme avoids contention among multiple lightpath requests by making
each node-pair to perform wavelength conversion at different intermediate nodes with more idle
converters.
Our proposed scheme sets up the requested lightpath with the following steps:
1) Construction of auxiliary graph based on link state information on the route
2) Calculation of wavelength conversion cost on intermediate nodes with idle converters
3) Determination of the wavelengths and converters that are assigned to the lightpath
4) Reservation of those wavelengths and converters
Given a route of a requested lightpath and link-state information on the route, our scheme first
constructs an auxiliary graph. The graph represents wavelength and converter usage information
5. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
67
on a route of a lightpath. Figure 4 shows an example of the auxiliary graph on a route with six
nodes in Fig. 3. In the graph, a vertex corresponds to an input or output port of a node, an edge
between different nodes corresponds to a wavelength, and an edge within the same node
corresponds to a connection between input and output ports. In addition, the source (destination)
node has a vertex corresponding to traffic-source (traffic-destination) instead of those
corresponding to input (output) ports. Note that using edges connecting an input port to an output
port on different wavelength means converting an input wavelength to a different one with a
wavelength converter.
Node v1Node S
Used wavelength
Idle wavelength
Idle wavelength converter
Used wavelength converter
WC
WC
Used wavelength
Idle wavelength
Idle wavelength converter
Used wavelength converter
WC
WCWC
WC
WC
WC
WC
WC
WC
WC
WC
WC
WC
WC
WC
WC
WC
WC
WC
ᕇ2
ᕇ3
ᕇ4
ᕇ2
ᕇ3
ᕇ4
Node v2 Node v3 Node v4 Node D
ᕇ1
Link e1 Link e2 Link e3 Link e4 Link e5
Figure 3. Route with six nodes (number of multiplexed wavelengths: 4)
Edge with cost Cost(vi)Edge with cost zeroEdge with cost zero
ᕇ1
ᕇ2
ᕇ3
ᕇ4
ᕇ1
ᕇ2
ᕇ3
ᕇ4
Node v1Node S Node v2 Node v3 Node v4 Node D
Source
Destination
Edge with cost infinityEdge with cost infinity
Figure 4. Auxiliary graph on a route with six nodes
Costs of edges are determined as follows. We assign zero to idle wavelengths while we assign
infinity to used ones. We assign zero to connections from traffic-source to output ports, those
from input ports to traffic-destination and those from an input port to an output port on the same
wavelength, while we assign wavelength conversion cost (Cost(vi)) to connection from an input
port to an output port on different wavelengths on node vi.
We define wavelength conversion cost (Cost(vi)) of intermediate node vi with idle converters as
follows:
Cost(vi
) =
Ui
Ai
(1)
where Ui is the proportion of the node-pairs that used wavelength converters on node vi in M
latest entries of wavelength converter usage history except the source-destination pair of the
requested lightpath, and Ai is the number of idle converters on node vi. By using Ui, we expect
6. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
68
that node-pairs tend to perform wavelength conversion on different intermediate nodes, and
consequently, contention among them is avoided. In addition, we expect that wavelength
converters are available on as many intermediate nodes as possible by using Ai.
After determining cost of each edge, our scheme performs Dijkstra algorithm on the auxiliary
graph and determines idle wavelengths and converters to be assigned to the lightpath so that the
sum of wavelength conversion costs is the minimum. When there are multiple wavelengths with
the same wavelength conversion cost, our scheme selects the wavelength with the minimum index
(i.e., First-Fit policy). If idle wavelengths and converters are found, the lightpath is successfully
set up, otherwise it is blocked.
We show an example of establishing a lightpath with our proposed scheme on the route with six
nodes in Fig. 3. Intermediate nodes v1, v2, v3 and v4 have zero , two, one and zero idle converters,
respectively. The number of entries in wavelength converter usage history (M) is three. The entry
of wavelength converter usage history of intermediate nodes with idle converters are shown in
Tab. 1. The wavelength converter usage history on node v2 consists of node-pairs (S, D), (v1, D)
and (S, v4). This means that the three node-pairs performed wavelength conversion on node v2 in
the past. Similarly, the wavelength converter history of node v3 has (v1, D), (v2, D) and (v2, v4). In
this case, Cost(v2) = (2/3)/2 = 1/3, and Cost(v3) = (3/3)/1 = 1. By applying Dijkstra algorithm, our
proposed scheme selects the following wavelengths and converters with the minimum cost: !1
on
links e1 and e2, a wavelength converter on node v2 and !2
on links e3, e4 and e5.
Table 1. Converter usage history of intermediate node with idle converters (M = 3)
Node Latest 2nd
latest 3rd
latest
v2 (S, D) (v1, D) (S, v4)
v3 (v1, D) (v2, D) (v2, v4)
4. PERFORMANCE EVALUATION
4.1. Simulation Model
We compare our proposed scheme with conventional schemes, FLR and LEC. As network model,
we use 16-node mesh network (Fig. 5) and 14-node NSFNET (Fig. 6). The number of
wavelengths multiplexed on each fiber is set to 16. We deploy identical number of wavelength
converters on each node. The number of lightpath requests follows Poisson distribution with rate
! . Lightpath holding time follows exponential distribution with rate 1/ µ . We define traffic load
as ! / µ [Erlang]. We adopt least load routing (LLR) that selects the route with the most idle
wavelengths among candidate routes. In LLR, the number (P) of candidate routes is set to four or
eight. We set wavelength usage history size (M) to ten because our simulation results for various
wavelength usage history sizes confirmed that size more than ten achieves almost the same
lightpath blocking probability.
7. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
69
Figure 5. 16-node mesh network
Figure 6. 14-node NSFNET
4.1. Evaluation Results
Figures 7 and 8 show lightpath blocking probability as a function of the number of converters per
node in mesh network. Our proposed scheme achieves lower blocking probability than FLR and
LEC when the number of converters per node ranges between 2 and 10. Compared with FLR and
LEC, out proposed scheme decreases blocking probability by about 44% for P = 4 and by about
83% for P = 8 at the maximum.
On the other hand, our proposed scheme shows almost the same blocking probability as the
conventional schemes when the number of converters per node is too small (e.g., less or equal to
2) or too large (e.g., greater or equal to 10). This is explained as follows. When the number of
converters per node is too small, we have little chance to perform wavelength conversion and the
performance improvement by wavelength conversion is small. Thus, there is little difference in
blocking probability among different schemes. When the number of converters per node is too
large, the wavelength continuity constraint is eliminated by the enough conversion capacity and
blockings are only caused by lack of wavelength resource. Therefore, in this case, there is also
little difference in blocking probability among different schemes.
8. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
70
10-6
10
-5
10
-4
10
-3
10
-2
10-1
0 2 4 6 8 10
Blockingprobability
Number of Converters per Node
100Erlang, FLR
100Erlang, LEC
100Erlang, Propsed(M=10)
120Erlang, FLR
120Erlang, LEC
120Erlang, Proposed(M=10)
Figure 7. Lightpath blocking probability (mesh network, P=4)
10-8
10-7
10
-6
10
-5
10
-4
10
-3
10
-2
10
-1
0 2 4 6 8 10 12 14
Blockingprobability
Number of Converters per Node
100Erlang, FLR
100Erlang, LEC
100Erlang, Proposed(M=10)
120Erlang, FLR
120Erlang, LEC
120Erlang, Proposed(M=10)
Figure 8. Lightpath blocking probability (mesh network, P=8)
We next evaluate the minimum number of wavelength converters per node in order to achieve
near optimal blocking performance. We regard the minimum number (X) that satisfies the
following equation [23] as the minimum number of converters.
PB
(X )! PB
(!)
PB
(0)! PB
(!)
=! (2)
PB
(0) / PB
(!) / PB
(X ) are blocking probabilities when no/infinite/X converters are deployed on
each node, respectively. We set 0.001 to ! .
Table 2 depicts X for each scheme. For different traffic load and the number of candidate routes,
our proposed scheme shows one or two fewer converters per node than FLR and LEC. This
means that, from the viewpoint of the whole network, our proposed scheme can decrease the total
number of converters by between sixteen and thirty-two.
9. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
71
Table 2. Minimum number of converters per node in order to achieve
near optimal blocking probability (mesh network)
100 Erlang 120 Erlang
P = 4 P = 8 P = 4 P = 8
FLR 5 5 8 9
LEC 5 5 8 9
Proposed 4 4 7 7
Figures 9 and 10 show lightpath blocking probability as a function of the number of converters
per node in NSFNET. Similarly to those in mesh network, our proposed scheme achieves lower
blocking probability than FLR and LEC when the number of converters per node ranges between
2 and 10. Compared with FLR and LEC, out proposed scheme decreases blocking probability by
about 57% for P = 4 and by about 60% for P = 8 at the maximum.
Table 3 summarizes the minimum number of converters per node to achieve near-optimal
blocking probability for each scheme. Our proposed scheme shows one fewer converters per node
than FLR while it shows the same number of converters per node as LEC for 100 Erlang and one
fewer converters than LEC for 120 Erlang.
5. CONCLUSIONS
In this paper, we have proposed a wavelength and converter assignment scheme in wavelength-
routed networks. Our scheme avoids contention among multiple lightpath requests by making
each node-pair to perform wavelength conversion at different intermediate nodes with more idle
converters. Our scheme realize this by using statistical information learned from wavelength
converter usage history and the number of idle converters on intermediate nodes. Simulation
results show that our scheme decreases blocking probability by about between 44% and 83% and
our scheme needs one or two fewer wavelength converters per node to achieve near-optimal
blocking probability compared with conventional schemes. We conclude that wavelength
converter usage history is useful for distributing wavelength conversion point of node-pairs and
decreasing lightpath blocking probability.
10-7
10-6
10
-5
10
-4
10
-3
10-2
10-1
0 2 4 6 8 10
Blockingprobability
Number of Converters per Node
100Erlang, FLR
100Erlang, LEC
100Erlang, Proposed(M=10)
120Erlang, FLR
120Erlang, LEC
120Erlang, Proposed(M=10)
Figure 9. Lightpath blocking probability (NSFNET, P=4)
10. International Journal of Computer Networks & Communications (IJCNC) Vol.5, No.4, July 2013
72
10
-7
10-6
10
-5
10
-4
10-3
10-2
10
-1
0 2 4 6 8 10 12 14
Blockingprobability
Number of Converters per Node
100Erlang, FLR
100Erlang, LEC
100Erlang, Proposed(M=10)
120Erlang, FLR
120Erlang, LEC
120Erlang, Proposed(M=10)
Figure 10. Lightpath blocking probability (NSFNET, P=8)
Table 3. Minimum number of converters per node in order to achieve
near optimal blocking probability (NSFNET)
100 Erlang 120 Erlang
P = 4 P = 8 P = 4 P = 8
FLR 5 5 8 9
LEC 4 4 8 9
Proposed 4 4 7 8
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