Optical Burst Research Articles

Burst Header Packet Flood Detection in Optical Burst Switching Network Using Deep Learning Model

The Optical Burst Switching (OBS) network is mostly victimized to the Denial of Service (DOS) attack, referred as Burst Header Packet (BHP) flooding attack can prevent reasonable traffics from keeping the necessary resources at transitional core nodes. The attack scenario is to flood the malicious BHP without acknowledging Data Bursts (DB) which can affect low bandwidth utilization, degrade network performance, high data loss rate and ultimately DOS. Therefore, machine predicted analysis has become very promising in recent decades that can effectually identify the attack in the optical switching network. However, due to a very small number of samples of the datasets, traditional machine learning approaches such as Naïve Bayes, K-Nearest Neighbour’s (KNN) and Support Vector Machine (SVM) cannot analyse the data efficiently. In this regard, we intend a Deep Convolution Neural Network (DCNN) model to automatically detect the edge nodes at an early stage. Finally, presented that proposed deep model is working enhanced rather than any other traditional model (e.g. Naïve Bayes, SVM and KNN).

Secured Hash Based Burst Header Authentication Design for Optical Burst Switched Networks

AbstractThe optical burst switching (OBS) is a promising technology that could meet the fast growing network demand. They are featured with the ability to meet the bandwidth requirement of applications that demand intensive bandwidth. OBS proves to be a satisfactory technology to tackle the huge bandwidth constraints, but suffers from security vulnerabilities. The objective of this proposed work is to design a faster and efficient burst header authentication algorithm for core nodes. There are two important key features in this work, viz., header encryption and authentication. Since the burst header is an important in optical burst switched network, it has to be encrypted; otherwise it is be prone to attack. The proposed MD5&RC4-4S based burst header authentication algorithm runs 20.75 ns faster than the conventional algorithms. The modification suggested in the proposed RC4-4S algorithm gives a better security and solves the correlation problems between the publicly known outputs during key generation phase. The modified MD5 recommended in this work provides 7.81 % better avalanche effect than the conventional algorithm. The device utilization result also shows the suitability of the proposed algorithm for header authentication in real time applications.

Performance evaluation of TCP over software-defined optical burst-switched data centre network

In this paper, we consider the performance of TCP when used in data centre networks (DCNs) featuring optical burst switching (OBS) using two-way reservation. The two-way reservation is not suitable in wide-area OBS networks due to high bandwidth-delay product (BDP). The burst loss using traditional methods of one-way reservation can be mistakenly interpreted by the TCP layer as congestion instead of contention in OBS network, leading to serious degradation of the TCP performance. The reduced BDP in DCNs allows the use of two-way reservation that results in zero burst loss. The modelled architecture features fast optical switches in a single hop topology. We apply different workloads with various burst assembly parameters to evaluate the performance of TCP. Our results show significant improvement in TCP performance as compared to traditional methods of OBS as well as to a conventional electronic packet switching DCN.

A partial-success-rate-based resource reservation scheme for slotted OBS networks

Optical burst switching (OBS) is a promising technology for next-generation optical networks. Slotted OBS is an improved version of OBS to reduce burst loss rate, in which wavelength channels are divided into time slots. Slotted OBS has an implicit and under-used property that resources for two bursts with the same source and the same destination are interchangeable. The property further means that resource for a long-distance burst can be partially used by a short-distance burst. In this paper, we utilize the property to design a resource reservation scheme for slotted OBS networks. The scheme reserves a batch of slots every time; the specific number of slots is calculated according to number of arrived bursts and partial success rate (a newly introduced conception in this paper) at each node. Simulation results show that the proposed scheme can get lower burst loss rate, comparing with the well-performing two-way signaling scheme.

De-optical-line-terminal hybrid access–aggregation optical network for time-sensitive services based on software-defined networking orchestration

With the increase in varieties of services in network, time-sensitive services (TSSs) appear and bring forward an impending need for delay performance. Ultralow-latency communication has become one of the important development goals for many scenarios in the coming 5G era (e.g., robotics and driverless cars). However, the conventional methods, which decrease delay by promoting the available resources and the network transmission speed, have limited effect; a new breakthrough for ultralow-latency communication is necessary. We propose a de-optical-line-terminal (De-OLT) hybrid access–aggregation optical network (DAON) for TSS based on software-defined networking (SDN) orchestration. In this network, low-latency all-optical communication based on optical burst switching can be achieved by removing OLT. For supporting this network and guaranteeing the quality of service for TSSs, we design SDN-driven control method and service provision method. Numerical results demonstrate the proposed DAON promotes network service efficiency and avoids traffic congestion.

A Study of the Number of Wavelengths Impact in the Optical Burst Switching Core Node

A Study of the Number of Wavelengths Impact in the Optical Burst Switching Core Node

QoS aware routing and wavelength allocation in optical burst switching networks using differential evolution optimization

The issue of burst losses imposes a constraint on the development of Optical Burst Switching (OBS) networks. Heavy burst losses strongly affect the Quality of Service (QoS) intended by end users. This article presents a QoS aware Routing and Wavelength Allocation (RWA) technique for burst switching in OBS networks. The RWA problem is modeled as a bi-objective Integer Linear Programming (ILP) problem, where objective functions are based on minimizing the number of wavelengths used and the number of hops traversed to fulfill the burst transmission requests for a given set of node pairs. The ILP model is solved using a novel approach based on a Differential Evolution (DE) algorithm. Analytical results show that the DE algorithm provides a better performance compared to shortest path routing, which is a widely accepted routing strategy for OBS networks.

A search for optical bursts from the repeating fast radio burst FRB 121102

We present a search for optical bursts from the repeating fast radio burst FRB 121102 using simultaneous observations with the high-speed optical camera ULTRASPEC on the 2.4-m Thai National Telescope and radio observations with the 100-m Effelsberg Radio Telescope. A total of 13 radio bursts were detected, but we found no evidence for corresponding optical bursts in our 70.7-ms frames. The 5-sigma upper limit to the optical flux density during our observations is 0.33 mJy at 767nm. This gives an upper limit for the optical burst fluence of 0.046 Jy ms, which constrains the broadband spectral index of the burst emission to alpha < -0.2. Two of the radio pulses are separated by just 34 ms, which may represent an upper limit on a possible underlying periodicity (a rotation period typical of pulsars), or these pulses may have come from a single emission window that is a small fraction of a possible period.

A distributed ant-based algorithm for routing and wavelength assignment in an optical burst switching flexible spectrum network with transmission impairments

This work describes a distributed algorithm inspired by ant colony optimisation for a solution to the problem of dynamic routing and wavelength assignment with wavelength continuity constraint in optical burst switched networks. The evaluation was conducted in a wavelength division multiplexed network environment with limited number of wavelength channels and in a flexible spectrum network environment undergoing transmission impairments. The simulations in the flexible spectrum network environment aim to replicate the effects of both linear and nonlinear physical layer impairments. Under these effects, an optical burst control packet could be lost during traversal of the network with no measure in place to notify the network of the loss or to free up optical resource reservations. The optical burst switching acknowledgement protocol has been modified in this work to account for a burst control packet failure by implementing a traversal acknowledgement to cater for its loss. The performance of the distributed ant-based algorithm has been extensively evaluated on several network topologies and compared with that obtained by shortest path routing and ant colony routing and wavelength assignment. The results show that the distributed ant-based algorithm significantly improves the burst transmission success probability in the wavelength division multiplexed network environment and provides a good solution in the flexible spectrum network environment undergoing transmission impairments.

Unified study of Quality of Service (QoS) in OPS/OBS networks

Abstract With the growth of Internet traffic, an inevitable use of optical networks provide a large bandwidth, fast data transmission rates and Quality of Service (QoS) support. Currently, Optical Burst Switched (OBS)/Optical Packet Switched (OPS) networks are under study as future solutions for addressing the increase demand of Internet traffic. However, due to their high blocking probability in the intermediate nodes they have been delayed in the industries. Packet loss in OBS/OPS networks is mainly occur due to contention. Hence, the contribution of this study is to analyze the file loss ratio (FLR), packet overhead and number of disjoint paths, and processing delay over Coded Packet Transport (CPT) scheme for OBS/OPS network using simulation. The simulations show that CPT scheme reduces the FLR in OBS/OPS network for the evaluated scenarios since the data packets are chopped off into blocks of the data packet for transmission over a network. Simulation results for secrecy and survivability are verified with the help of the analytical model to define the operational range of CPT scheme.

Single-wavelength optical buffers with general burst size distribution: Blocking probability and mean delay

As an emerging novel technology, optical buffering via fiber delay lines (FDLs) is adopted in optical burst switching (OBS) networks for contention resolution. In this paper, we study the blocking probability and the mean delay of an asynchronous single-wavelength optical buffer, where the burst arrival process is Poisson and burst-length distribution is general. With the aid of Level Crossing (LC) method, we first derive the integral equations to model the dynamics of the buffer. We then propose a method to solve these equations. Finally we present the mathematical expressions of blocking probabilities and the mean delays for the optical buffer with general burst size distribution. Numerical examples are provided to validate our results, and some interesting observations from the numerical examples are highlighted.

CSI 2264: Simultaneous optical and X-ray variability in pre-main sequence stars

Pre-main sequence stars are variable sources. In stars with disks, this variability is related to the morphology of the inner circumstellar region (<0.1 AU) and that of the photosphere and corona, all impossible to be spatially resolved with present day techniques. This has been the main motivation for the Coordinated Synoptic Investigation of NGC 2264. In this paper, we focus on the stars with disks. We analyze the X-ray spectral properties extracted during optical bursts and dips in order to unveil the nature of these phenomena. We analyze simultaneous CoRoT and Chandra/ACIS-I observations to search for coherent optical and X-ray flux variability in stars with disks. Then, stars are analyzed in two different samples. In stars with variable extinction, we look for a simultaneous increase of optical extinction and X-ray absorption during the optical dips; in stars with accretion bursts, we search for soft X-ray emission and increasing X-ray absorption during the bursts. Results. We find evidence for coherent optical and X-ray flux variability among the stars with variable extinction. In 9/24 stars with optical dips, we observe a simultaneous increase of X-ray absorption and optical extinction. In seven dips, it is possible to calculate the NH/AV ratio in order to infer the composition of the obscuring material. In 5/20 stars with optical accretion bursts, we observe increasing soft X-ray emission during the bursts that we associate to the emission of accreting gas. It is not surprising that these properties are not observed in all the stars with dips and bursts, since favorable geometric configurations are required. The observed variable absorption during the dips is mainly due to dust-free material in accretion streams. In stars with accretion bursts, we observe on average a larger soft X-ray spectral component not observed in non accreting stars.

Up to 400 GHz burst-mode pulse generation from a hybrid harmonic mode-locked Er-doped fibre laser

By inserting a birefringence filter with FSR = 100 GHz inside a hybrid mode-locked Er-doped fibre laser, we successfully generate ps to sub-ps optical burst pulses with the intra-burst pulse rate up to 400 GHz. Multiplication of the intra-burst pulse rate is attributed to a new effect analogous to rational harmonic mode-locking, which occurs due to the relative alignment of the cavity harmonic frequencies, the external phase modulation induced frequencies, and the filter-selected frequencies.

Optical switching based small-world data center network

Redesigning data center networks, particularly taking advantages of optical switching technologies to reduce cost-per-bandwidth and energy consumption, has spawned interests of researchers worldwide in recent years. In this paper, we introduce and analysis our recently proposed optical switching technology powered data center network architecture, which is inspired from the small world data center network topology yet has additional flexibility brought by optical lightpath's reconfigurability. Specifically, logically full-meshed optical burst switching rings are employed to compose a lattice substrate, which provide dense connectivity for small groups of ToR switches to accommodate highly clustered and dynamic regional data traffic, while a reconfigurable wavelength circuit switching plane offers direct connections among the racks to effectively reduce overall network diameter. A centralized control plane is employed to realize traffic-adaptive optical lightpath scheduling mechanisms. We thoroughly study the throughput and latency performance of the proposed architecture through numerical simulations, and particularly reveal the impact of traffic patterns. It turns out that, the proposed network architecture can achieve high throughput with significantly reduced cost, and exploiting its traffic-adaptive reconfiguration capability can effectively improve throughput and reduce latency under varying traffic distributions.

Построение и анализ модели входного коммутатора в сети с оптической коммутацией

Currently, there are two generally recognized principles of switching of information signals in high-speed networks: networks with wave routing, and networks with the principle of optical packet switching. In networks with wave routing it is not required to produce opto-electrical and electro-optical conversions and to create a buffer, but with this switching principle the working range of wavelengths is not efficiently used. In networks with optical packet switching the traffic is transmitted in packets, which consist of a header and an information part of a consistent size. In this case, using of the frequency range is the most complete, but there is a need of optical-electronic conversions. In an effort to combine the advantages of two optical switching technologies, a new combined switching principle was proposed, called optical switching bursts. In this technology there are not buffering and electronic processing in intermediate nodes, there is a reservation of the channel for a limited time. For the effective implementation of such a network connection, we must calculate its probability characteristics. To assess probabilistic characteristics of the network the methods of theory of mass service are widely used. The input switch is one of the key devices on the network. The article describes the input switch of the network with the optical switching of bursts, calculates the probable characteristics of the network using analytical and simulation models. Examples of the calculation of the probability of blocking of packets flowing in the input switch are presented.

Bufferless Bidirectional Multi-Ring Networks with Sharing an Optical Burst Mode Transceiver for Any Route

Bufferless Bidirectional Multi-Ring Networks with Sharing an Optical Burst Mode Transceiver for Any Route

An enhanced burst assembly scheme over optical burst switching networks

An enhanced burst assembly scheme over optical burst switching networks

An enhanced burst assembly scheme over optical burst switching networks

Recently, real-time traffic occupied a large portion of the internet's traffic, which has strict quality of service (QoS) requirements in terms of delay. Thus, guaranteeing the network end-to-end delay is one of the main important factors to guarantee the QoS for the real time traffic over the internet. Constant bit rate (CBR) traffic is one of the real time traffic forms that have been proposed as a solution for reducing the size of transmission and storage. In optical burst switching (OBS) network, the entire delay is calculated based on the collection of the burst assembly time, the offset time, and the propagation delay. Thus, the OBS must be able to guarantee the delay requirements of CBR traffic as real time traffic. This paper introduces a novel OBS burst assembly scheme called burst assembly with CBR traffic delay requirements (BACDR) scheme that guarantees the delay requirements of CBR traffic over OBS networks. The results showed that the BACDR scheme can guarantee the delay requirements of CBR traffic under various conditions such traffic load, the value of maximum packet transfer delay, or the design of the network topology.

Study of Qos Performance in Optical Burst Switched Networks (OBS)

One of the main challengers of the future Internet is to ensure QoS for various types of traffic characteristics with differentiated service requirements. It has been highlighted that OBS can provide high bandwidth data transmission in alloptical Internet network. However, the provisioning of QoS in OBS network is still an issue. The focused of this study is to develop QoS provisioning mechanism at the ingress and core node of OBS network. The proposed QoS provisioning ensures that the differentiated traffic is able to achieve their respective demands. This study proposed a DiffServ-aware ingress node with priority queueing (PQ) and burst assembly mechanisms. In addition, a core node with contention resolution scheme using FDL_WA_WPremp is developed as part of the integration of the proposed OBS network.

Priority based Burst Assembly for Optical Burst Switched Network

Objective: In this paper, burst is aggregated on the basis of priority of the packets coming from different networks at the edge node of the optical network to enhance the QoS parameters such as burst drop, delay, packet delivery ratio and packet error. Methods: To reduce traffic related problems in optical switched network different algorithms are used to assemble the bursts and their scheduling in the core network. Bursts are assembled on the basis of time, length and hybrid technique which are scheduled in the core network to reach the edge node and then to their actual or true destinations.In this study, bursts are aggregated on the basis of priority of packets coming from different networks to enhance the network parameters. High and low priority packets are aggregated separately into ht bursts on the basis of which bursts of high priority packets followed by bursts of low priority packets are scheduled in the network. After reaching at edge node, bursts are dissembled into packets and then sent to their actual destinations. Findings: The proposed algorithm is simulated in MATLAB with dynamic number of nodes (50-60 for better results) on area of 2000 * 2000 units. Priority based burst assembly algorithm is used for aggregation of bursts and it has been analyzed in terms of network parameters such as delay, packet error, burst drop and burst delivery ratio. Applications: the main application of OBS network is at the backbone of Internet due to which the usage of Internet is easy and faster because data is sent on different bandwidths at the same time.