Optical Burst Switching Networks Research Articles

Design and Implementation of an Adaptive Assembly Algorithm for Edge Nodes of Satellite OBS Networks

The edge nodes of the satellite optical burst switching network are the interface devices of the ground network and the satellite optical burst network. Ground network data needs to be classified, assembled, and generated bursts at the edge nodes. The burst will be transmitted on different wavelength channels. Reasonable selection of the assembly algorithm of the edge nodes can reduce the design complexity and improve the forwarding performance and QoS capability of the satellite optical burst switching network. In this paper, an adaptive assembly algorithm is proposed to adjust the length threshold and time threshold dynamically. The basic principle is to evaluate current network traffic depend on the actual burst parameters of previous bursts, and then determine the specific value of length threshold and time threshold. The algorithm is implemented on a Xilinx’s XC7VX690T-2FFG1927I FPGA, and verified by Modelsim SE 10.6d.

Adaptive burst reordering for burst-cluster transmission to improve fairness in OBS networks

In hop-based burst-cluster transmission, multiple bursts are assembled simultaneously and sorted from the smallest number of hops to the largest one. By doing so, the burst loss probability for a large number of hops decreases, improving fairness. How- ever, in mesh networks, the amount of trac on each link is not necessarily the same, and hence degrades the performance of hop-based burst-cluster transmis- sion. In this paper, we propose dynamic burst or- dering to solve this problem. Here, each source node calculates the burst loss probability for each number of hops using ACK and NACK messages. Based on the calculated probabilities, the source node changes the order of bursts within a burst-cluster dynami- cally. It is expected that this method can improve local fairness for each source node. We evaluate the performance of the proposed method in tandem net- works by simulation. Numerical examples show that the proposed method is eective for improving fair- ness for each source node regardless of the amount of trac on each link.

Hybrid approach for a reliable bufferless OBS network with reduced end-to-end delay and burst loss

Optical burst switching (OBS) is a very efficient all optical transmission network. But the performance of the network may reduce because of the burst losses. Hence, to eliminate the collision and dropping of packets at the core nodes we have proposed a hybrid approach for a reliable bufferless OBS network known as an enhanced multipath adaptive burst assembly algorithm (EMP-ABAA). In this technique based on the priority and type of users (i.e., regular users with lesser priority and premium users with high priority), data packets are routed efficiently. At the core nodes the relative drop in data packet, delivery ratio, delay and energy consumption is evaluated in comparison with FAHBA approach. From the simulation results, using NS2 simulation, it is observed that the proposed approach outperforms FAHBA approach; hence enhancing the efficiency and reliability of the OBS network with lesser overhead utilisation in the network.

Hybrid approach for a reliable bufferless OBS network with reduced end-to-end delay and burst loss

Hybrid approach for a reliable bufferless OBS network with reduced end-to-end delay and burst loss

Correction to: A controllable deflection routing and wavelength assignment algorithm in OBS networks

The article, A controllable deflection routing and wavelength assignment algorithm in OBS networks, written by Philani Khumalo, Bakhe Nleya, Andrew Mutsvangwa, was originally published electronically on the publisher’s Internet portal.

A controllable deflection routing and wavelength assignment algorithm in OBS networks

Heterogeneous IoT-enabled networks generally accommodate both jitter-tolerant traffic and jitter-intolerant traffic. Optical burst-switched backbone networks are handling the resultant volumes of such traffic by transmitting it in huge-size chunks called bursts. Because of the lack or limited buffering capabilities within the core network, contentions as well as congestion may frequently occur, thus affecting overall supportable quality of service (QoS). Both contention and congestion will be characterized by frequent burst losses, especially when traffic levels surge. The congestion is normally resolved by way of deflecting contending bursts to other less congested paths even though this may lead to differential delays incurred by bursts as they traverse the network. This will contribute to undesirable jitter that may ultimately compromise overall QoS. Noting that jitter is mostly caused by deflection routing which itself is a result of poor wavelength and routing assigning, in this paper we propose a controllable deflection routing scheme that allows the deflection of bursts to alternate paths only after controller buffer preset thresholds are surpassed. In this way, bursts intended for a common destination are always most likely to be routed on the same or least-cost path end-to-end. We describe the scheme and compare its performance to other existing approaches. Both analytical and simulation results overall show that the proposed scheme does lower both congestion and jitter, thus also improving throughput as well as avoiding congestion on deflection paths.

A Semi-Supervised Machine Learning Approach Using K-Means Algorithm to Prevent Burst Header Packet Flooding Attack in Optical Burst Switching Network

Optical burst switching (OBS) network is a new generation optical communication technology. In an OBS network, an edge node first sends a control packet, called burst header packet (BHP) which reserves the necessary resources for the upcoming data burst (DB). Once the reservation is complete, the DB starts travelling to its destination through the reserved path. A notable attack on OBS network is BHP flooding attack where an edge node sends BHPs to reserve resources, but never actually sends the associated DB. As a result the reserved resources are wasted and when this happen in sufficiently large scale, a denial of service (DoS) may take place. In this study, we propose a semi-supervised machine learning approach using k-means algorithm, to detect malicious nodes in an OBS network. The proposed semi-supervised model was trained and validated with small amount data from a selected dataset. Experiments show that the model can classify the nodes into either behaving or not-behaving classes with 90% accuracy when trained with just 20% of data. When the nodes are classified into behaving, not-behaving and potentially not-behaving classes, the model shows 65.15% and 71.84% accuracy if trained with 20% and 30% of data respectively. Comparison with some notable works revealed that the proposed model outperforms them in many respects.

A Brief Review on the Methods that Improve Optical Burst Switching Network Performance

Abstract In this tutorial, we give an introduction to optical burst switching (OBS) networks and compare different methods that have been given to improve performance of these networks. OBS is an alternative to optical circuit switching and optical packet switching by separating data from control packets and sending them in a different wavelength. OBS networks suffer from an issue based on their bufferless nature, burst contentions. In these networks, when two data bursts are competing on the same wavelength, one of them is dropped and it leads to a significant reduction on the performance of the network. A lot of researches have been done to solve this problem. Some of them are addressed in this paper.

Optical Burst Routing by Balanced Wavelength Allocation Under Multi-objective Quality Metrics

The optical burst switching is promising optical network technique that intends to transmit data in the form of bursts with the ability of dynamic switching between sub-wave lengths. One among the crucial issues of the OBS networks is burst loss due to suboptimal and often impediment burst scheduling and wavelength allocation strategies. Hence, the major contributions of the contemporary research in regard to OBS networks entails to portray the optimal burst routing strategies. The contribution of this manuscript is balanced wavelength allocation using differential evolution method in short referred as BWADE, which selects an optimum multi-hop route that intends to uses multi-objective QoS aspects as a fitness scale for differential evolution algorithm. The experimental study concluding that the proposed BWADE outperforming the other contemporary routing approaches through simulation outcomes.

Improving optical burst switching networks (OBS) performance by adjusting maximum burst size and burstification time

Improving optical burst switching networks (OBS) performance by adjusting maximum burst size and burstification time

Mô hình hàng đợi retrial cho đường trễ quang FDL tại nút lõi OBS xét chất lượng dịch vụ QoS

Optical Burst Switching networks are considered as an important candidate for future transport networks. Many analysis models of the OBS core node with FDLs have been proposed recently. Our paper proposes a novel retrial queueing model at OBS core node architecture SPL - feed-forward with QoS. Blocking probability will be calculated based on Markov multi-dimensional models. Numerical results from the proposed analysis method are compared with simulation, as well as between these model.

Improving Performance of Optical Networks by a Probable Approach

Abstract Optical Burst Switching (OBS) networks are new emerging techniques that alternate Optical Circuit Switching (OCS) and Optical Packet Switching (OPS) techniques. The high bandwidth of fiber links in these networks, besides WDM (Wavelength Division Multiplexing) helps the Internet to handle the heavy traffic. OBS networks have an important issue that needs to be tackled. These networks are bufferless in their nature, so when two bursts are trying to reserve one wavelength one of them is dropped. This drop can be assumed as an indicator of congestion; as a result, the sending rate will be decreased, despite the fact that the network may not be congested. So, wired protocols like TCP (Transmission Control Protocol) cannot work to their high potential in OBS networks. In this paper, we propose a new scheme based on a probable approach that can distinguish burst drops caused by contentions from burst drops caused by contention, so we can improve the performance of the network. Extensive simulative studies show that the proposed algorithm outperforms TCP Vegas in terms of throughput and packet delivery count.

The automated detection of microearthquakes on continuous noisy records of local OBS and coastal networks

The automated detection of microearthquakes on continuous noisy records of local OBS and coastal networks

A Retrial Queueing model with FDL at OBS core node

Optical Burst Switching networks are considered as an important candidate for the future transport networks. Many analysis models of OBS node with FDLs have been proposed recently. In this paper, we propose a novel retrial queueing model at OBS core node architecture SPL - feed-forward. Blocking probability will be calculated based on Markov multi-dimensional models. Numerical solution values from the proposed analysis method are compared with simulation, as well as between these models.

A Novel Implementation of TCP Vegas by UsingA Fuzzy-Threshold Base Algorithm to Improve Performance of Optical Networks

Abstract There is a misunderstanding in Optical Burst Switching (OBS) networks about the congestion status in the network that can cause a reduction in the performance of the networks. OBS networks are bufferless in their nature so when a burst drop happens in the network it can be because of the congestion or contention in the network but TCP cannot distinguish it is due to the congestion or contention. TCP wrongly decreases the congestion window size (cwnd) and causes significant reduction of the network performance. In this paper we are trying to employ a new algorithm by using fuzzy logic and some thresholds to divide the network into several areas then we can solve the problem. This new scheme can help us to distinguish a burst drop is because of the congestion or a burst contention in the network. Extensive simulative studies show that the proposed algorithm outperforms TCP Vegas in terms of throughput and packet delivery count.

Improving Performance of Optical Networks by Using FRPI Algorithm

Abstract Optical burst switching (OBS) is a new emerging network that is developing rapidly. By increasing the amount of traffic on the Internet the necessity for having networks like OBS ones that can carry heavy traffic is needed. These networks have an important problem due to being bufferless. The congestion control of the network is a little confusing for some protocols like transport control protocol (TCP) Vegas as they are appropriate for conventional wired networks not optical ones. When a drop happens in OBS networks it can be because of two reasons: 1. congestion and 2. Contention that has been possible due to the bufferless nature of the network. When a contention happens and a packet drops, TCP thinks that the network is experiencing heavy load however it may not, and it decreases the sending rate, as a result, it leads to a reduction in the performance of the network. In this paper, we are trying to improve the performance of the network by employing a new algorithm that called Fuzzy-RTT Performance Improver. This algorithm is based on fuzzy logic and round-trip time measurements. Simulative results show that this algorithm outperforms TCP Vegas in terms of throughput and packet delivery count.

A positive–negative delayer for slotted OBS networks to enhance two-way signaling scheme

Optical burst switching (OBS) is a promising technology for next-generation optical networks and slotted OBS is one of its improved versions. Contention between bursts is the main defect in OBS (as well as slotted OBS) networks. Different strategies are proposed to resolve contentions, such as using fiber delay line (FDL) to delay one of the conflicting bursts, or adopting two-way signaling scheme to gather states of links in advance. Unfortunately, the above two strategies cannot be used together, because FDL would deviate a burst from its planned trajectory, which would eliminate the effect of link state gathering in two-way scheme. In this paper, we design a novel delayer with ordinary FDLs, which can generate both positive and negative delay. The delayer can be used in two-way scheme without affecting the efficacy of link state gathering. Simulation results show that the delayer can greatly reduce the blocking rate of two-way scheme, by just a slight expense of average delay.

Throughput-based fair bandwidth allocation in OBS networks

Throughput-based fair bandwidth allocation in OBS networks

Burst Assembly Framework for High Speed Optical Network

Optical Burst Switching (OBS) is promising technique to support requirements of high speed optical networks. OBS network ingress node assembles packets into bursts. Burst assembly criteria have to be optimally chosen based on network requirements. In this paper, burst assembly framework is presented which can support optimal time/size value selection during burst formation. It is observed that, network with high timeout supports high Transmission Control Protocol (TCP) throughput for a range of burst size. For lower burst timeout values, throughput performance degrades only for small size bursts and further reduction in timeout threshold degrades throughput for range of burst size.

A model of QoS differentiation burst assembly with padding for improving the performance of OBS networks

Burst assembly is an operation at the ingress node of optical burst switching (OBS) networks that aggregates incoming packets from various access networks into larger carriers, called bursts. Depending on the density of incoming packets and the preset time or length thresholds, the completed bursts may have various lengths, but they must be at least equal to a minimum value ($B_{\min})$ to facilitate the switching in existing physical optical switches. If a completed burst is smaller than $B_{\min}$, it should be padded by padded bytes and it results in bandwidth utilization inefficiency. One solution to the problem is increasing the assembly time so that completed bursts must be longer than or at least equal to $B_{\min}$. However, increasing the assembly time will result in increased end-to-end delay. This article proposes a model of QoS differentiation burst assembly with padding for improving the performance of OBS networks.