The optical burst switching (OBS) paradigm is perceived as an intermediate switching technology for future all-optical networks. Burst assembly that is the first process in OBS is the focus of this paper. In this paper, an intelligent... more
The optical burst switching (OBS) paradigm is perceived as an intermediate switching technology for future all-optical networks.
Burst assembly that is the first process in OBS is the focus of this paper. In this paper, an intelligent hybrid burst assembly algorithm
that is based on fuzzy logic is proposed.The new algorithmis evaluated against the traditional hybrid burst assembly algorithmand
the fuzzy adaptive threshold (FAT) burst assembly algorithm via simulation. Simulation results show that the proposed algorithm
outperforms the hybrid and the FAT algorithms in terms of burst end-to-end delay, packet end-to-end delay, and packet loss ratio
Burst assembly that is the first process in OBS is the focus of this paper. In this paper, an intelligent hybrid burst assembly algorithm
that is based on fuzzy logic is proposed.The new algorithmis evaluated against the traditional hybrid burst assembly algorithmand
the fuzzy adaptive threshold (FAT) burst assembly algorithm via simulation. Simulation results show that the proposed algorithm
outperforms the hybrid and the FAT algorithms in terms of burst end-to-end delay, packet end-to-end delay, and packet loss ratio
Research Interests:
Mobile ad hoc network (MANET) is used in a wide range of application from civilian usage to military battlefield communications. Using multi-hop communication model, a source node can directly communicate with the destination node without... more
Mobile ad hoc network (MANET) is used in a wide
range of application from civilian usage to military battlefield
communications. Using multi-hop communication model, a source
node can directly communicate with the destination node without
infrastructure. Unfortunately, this feature causes the network
vulnerable to various attacks. Security preventions implemented
in the traditional wired network are unsuitable for MANET. This
paper studies several types of attacks, and then discusses one of
the most severe attack in the network, blackhole attack.
Furthermore, recent efforts for preventing the blackhole attack
are comprehensively discussed. Study of literature indicates that
the prevention of the blackhole attack can be categorized into
three groups, i.e., Protection based on Cryptography, Protocol
Modification, and Intrusion Detection and Counter Measure.
range of application from civilian usage to military battlefield
communications. Using multi-hop communication model, a source
node can directly communicate with the destination node without
infrastructure. Unfortunately, this feature causes the network
vulnerable to various attacks. Security preventions implemented
in the traditional wired network are unsuitable for MANET. This
paper studies several types of attacks, and then discusses one of
the most severe attack in the network, blackhole attack.
Furthermore, recent efforts for preventing the blackhole attack
are comprehensively discussed. Study of literature indicates that
the prevention of the blackhole attack can be categorized into
three groups, i.e., Protection based on Cryptography, Protocol
Modification, and Intrusion Detection and Counter Measure.
Research Interests:
Optical Burst Switching (OBS) is envisioned as the intermediate candidate technology for the next generation all-optical switching networks. OBS has the capability to statistically multiplex data at the burst level and at the same time... more
Optical Burst Switching (OBS) is envisioned as the intermediate candidate technology for the next
generation all-optical switching networks. OBS has the capability to statistically multiplex data at the burst
level and at the same time function effectively without the need for optical memory. OBS harnesses the
Wavelength Division Multiplexing (WDM) capability of the optical fiber to transport large volume of data
by aggregating different client packets into a larger packet known as a burst. Burst assembly that is the
first process in OBS is the focus of this paper, and this is because of the crucial role burst assembly plays in the
performance of a network. The performance of burst assembly affects the congestion and contention levels of
the network which in turn affects the overall network performance in terms of delay and loss. In this paper,
a new burst assembly algorithm that uses fuzzy logic to adjust the threshold of the timer-based burst
assembly algorithm is proposed. The goal of the algorithm is to minimize loss and end-to-end delay.
Furthermore, two sets of fuzzy rules have been used to investigate the effects of different fuzzy rules
on the performance of the network. Through simulation, the new algorithm shows performance
improvement over the conventional timer-based assembly algorithm
generation all-optical switching networks. OBS has the capability to statistically multiplex data at the burst
level and at the same time function effectively without the need for optical memory. OBS harnesses the
Wavelength Division Multiplexing (WDM) capability of the optical fiber to transport large volume of data
by aggregating different client packets into a larger packet known as a burst. Burst assembly that is the
first process in OBS is the focus of this paper, and this is because of the crucial role burst assembly plays in the
performance of a network. The performance of burst assembly affects the congestion and contention levels of
the network which in turn affects the overall network performance in terms of delay and loss. In this paper,
a new burst assembly algorithm that uses fuzzy logic to adjust the threshold of the timer-based burst
assembly algorithm is proposed. The goal of the algorithm is to minimize loss and end-to-end delay.
Furthermore, two sets of fuzzy rules have been used to investigate the effects of different fuzzy rules
on the performance of the network. Through simulation, the new algorithm shows performance
improvement over the conventional timer-based assembly algorithm
Research Interests:
Optical burst switching (OBS) is the most favourable switching paradigm for future all-optical networks. Burst assembly is the first process in OBS and it consists of aggregating clients packets into bursts. Assembled bursts wait for an... more
Optical burst switching (OBS) is the most favourable switching paradigm for future all-optical networks.
Burst assembly is the first process in OBS and it consists of aggregating clients packets into bursts. Assembled
bursts wait for an offset time before being transmitted to their intended destinations. Offset time is used
to allow burst control packet reserve required resources prior to burst arrival. Burst assembly process and
offset-time create extra delay in OBS networks. To make OBS suitable for real time applications, this extra
latency needs to be controlled. This paper proposes and evaluates a novel offset time and burst assembly
scheme to address this issue. Constant bit rate (CBR) traffic that has stringent end-to-end delay QoS requirements
is used in this study. The proposed scheme is called hybrid offset-time and burst assembly algorithm
(H-OTBA). The objective of the paper is achieved by controlling maximum burst transfer delay parameters
of CBR. The proposed scheme was evaluated via network simulation. Simulation results demonstrate
that, H-OTBA has effectively reduced end-to-end delay for CBR traffic compared with current solutions.
Burst assembly is the first process in OBS and it consists of aggregating clients packets into bursts. Assembled
bursts wait for an offset time before being transmitted to their intended destinations. Offset time is used
to allow burst control packet reserve required resources prior to burst arrival. Burst assembly process and
offset-time create extra delay in OBS networks. To make OBS suitable for real time applications, this extra
latency needs to be controlled. This paper proposes and evaluates a novel offset time and burst assembly
scheme to address this issue. Constant bit rate (CBR) traffic that has stringent end-to-end delay QoS requirements
is used in this study. The proposed scheme is called hybrid offset-time and burst assembly algorithm
(H-OTBA). The objective of the paper is achieved by controlling maximum burst transfer delay parameters
of CBR. The proposed scheme was evaluated via network simulation. Simulation results demonstrate
that, H-OTBA has effectively reduced end-to-end delay for CBR traffic compared with current solutions.
Research Interests:
In this study, the effects of time slot parameters on the performance of time domain switching optical burst switched networks (OBS) are studied. We investigate OBS networks where all core nodes are able to receive and send data. Network... more
In this study, the effects of time slot parameters on
the performance of time domain switching optical burst switched
networks (OBS) are studied. We investigate OBS networks where
all core nodes are able to receive and send data. Network throughput
is reduced when bursts are not able to secure necessary time
slots for their transmission due to heavy contention at the core
networks and lack of proper selection of time slot parameters.
In this paper, we investigate the performance of slotted OBS
when time slot parameters are varied. Time slot parameters
investigated are: frame size, time slot size. Additionally, we
analyse the effect of network size when time slot and other
parameters are kept constant. Metrics used for evaluation are
delay and throughput. Simulation results prove that given the
same route, wavelength and time slot assignment algorithm, time
slot parameters influence the overall network performance
the performance of time domain switching optical burst switched
networks (OBS) are studied. We investigate OBS networks where
all core nodes are able to receive and send data. Network throughput
is reduced when bursts are not able to secure necessary time
slots for their transmission due to heavy contention at the core
networks and lack of proper selection of time slot parameters.
In this paper, we investigate the performance of slotted OBS
when time slot parameters are varied. Time slot parameters
investigated are: frame size, time slot size. Additionally, we
analyse the effect of network size when time slot and other
parameters are kept constant. Metrics used for evaluation are
delay and throughput. Simulation results prove that given the
same route, wavelength and time slot assignment algorithm, time
slot parameters influence the overall network performance
Research Interests:
Routing in sensor networks is very challenging compared to contemporary communication and wireless ad-hoc networks. This is attributed to several characteristics that distinguish them from such networks. Transmitting data from every... more
Routing in sensor networks is very challenging compared to contemporary communication
and wireless ad-hoc networks. This is attributed to several characteristics that distinguish them
from such networks. Transmitting data from every sensor node within the deployment region might
result in significant and unnecessary redundancy in data and incur avoidable energy and traffic
expenditure; thus, a routing protocol which is able to select a set of sensor nodes and utilise data
aggregation during the relaying of data is of great importance. Furthermore, timely delivery of data
is required in many applications of Wireless Sensor Networks (WSNs), such as real-time target
tracking in battle environments, emergent event triggering in monitoring applications impose the
need of efficient routing protocol. In this paper, we propose a data routing scheme which ensures
increased network lifetime by exploiting energy efficiently, supporting reliability, fast delivery of
delay-sensitive data and achieving low-cost sensor design. Simulation results demonstrate that, the
proposed routing scheme outperforms related existing approaches in terms of all the evaluation
metrics such as packet delivery ratio, energy efficiency and timely delivery of data.
and wireless ad-hoc networks. This is attributed to several characteristics that distinguish them
from such networks. Transmitting data from every sensor node within the deployment region might
result in significant and unnecessary redundancy in data and incur avoidable energy and traffic
expenditure; thus, a routing protocol which is able to select a set of sensor nodes and utilise data
aggregation during the relaying of data is of great importance. Furthermore, timely delivery of data
is required in many applications of Wireless Sensor Networks (WSNs), such as real-time target
tracking in battle environments, emergent event triggering in monitoring applications impose the
need of efficient routing protocol. In this paper, we propose a data routing scheme which ensures
increased network lifetime by exploiting energy efficiently, supporting reliability, fast delivery of
delay-sensitive data and achieving low-cost sensor design. Simulation results demonstrate that, the
proposed routing scheme outperforms related existing approaches in terms of all the evaluation
metrics such as packet delivery ratio, energy efficiency and timely delivery of data.
Research Interests:
Among the three optical network technologies being studied for future Internet, namely, Optical Circuit Switching, Optical Packet switching and Optical Burst switching; Optical Burst Switching is, up to now, the most likely to be... more
Among the three optical network technologies being
studied for future Internet, namely, Optical Circuit Switching,
Optical Packet switching and Optical Burst switching; Optical
Burst Switching is, up to now, the most likely to be
implemented in the near future. Nevertheless, bursts
contention persists and more work need to be done to minimize
bursts loss before Optical Burst switching can be implemented.
In this paper, we propose efficient bandwidth utilization and
routing optimization scheme aiming at avoiding bursts
contention and making better use of the large bandwidth
offered by fiber links through Wavelength Division
Multiplexing and Dense Wavelength Division Multiplexing.
The proposed solution is based on the Hierarchical Optical
Burst switching techniques and a modified hybrid algorithm of
Ant Colony Optimization and Genetic Algorithm, taking into
account the Streamline Effect in Optical Burst switching.
Through simulation, we expect low burst lost probability and
efficient use of bandwidth.
studied for future Internet, namely, Optical Circuit Switching,
Optical Packet switching and Optical Burst switching; Optical
Burst Switching is, up to now, the most likely to be
implemented in the near future. Nevertheless, bursts
contention persists and more work need to be done to minimize
bursts loss before Optical Burst switching can be implemented.
In this paper, we propose efficient bandwidth utilization and
routing optimization scheme aiming at avoiding bursts
contention and making better use of the large bandwidth
offered by fiber links through Wavelength Division
Multiplexing and Dense Wavelength Division Multiplexing.
The proposed solution is based on the Hierarchical Optical
Burst switching techniques and a modified hybrid algorithm of
Ant Colony Optimization and Genetic Algorithm, taking into
account the Streamline Effect in Optical Burst switching.
Through simulation, we expect low burst lost probability and
efficient use of bandwidth.
Research Interests:
The exact contribution of this paper is a review of existing state-of-the-art routing strategies for optical burst switched networks developed by researchers to deal with burst contention before it happens. Routing schemes are implemented... more
The exact contribution of this paper is a review of existing state-of-the-art routing strategies for optical
burst switched networks developed by researchers to deal with burst contention before it happens. Routing
schemes are implemented in space domain, which make them simple and cost effective. Additionally, the
paper points out the importance of routing as an effective way to deal with burst contention compared to other
solutions. It also underlines the main differences between contention avoidance schemes and contention resolution
techniques for optical burst switched networks.We believe that this review will help different optical
burst switched researchers involved in the development of route optimization algorithms to control burst
contention.
burst switched networks developed by researchers to deal with burst contention before it happens. Routing
schemes are implemented in space domain, which make them simple and cost effective. Additionally, the
paper points out the importance of routing as an effective way to deal with burst contention compared to other
solutions. It also underlines the main differences between contention avoidance schemes and contention resolution
techniques for optical burst switched networks.We believe that this review will help different optical
burst switched researchers involved in the development of route optimization algorithms to control burst
contention.