Sub-Tree-Based Approach for Reconfiguration of Light-Tree Pair without Flow Interruption in Sparse Wavelength Converter Network

Network reconfiguration is an important mechanism for network operators to optimize network performance and optical flow transfer. It concerns unicast and multicast connections. Multicast connections are required to meet the bandwidth requirements of multicast applications, such as Internet Protocol-based TeleVision (IPTV), distance learning, and telemedicine. In optical networks, a multicast connection is made possible by the creation of an optical tree-shaped path called a light-tree. The problem of light-tree pair reconfiguration is addressed in this study. Given an initial light-tree used to transfer an optical flow and a final light-tree that is computed by the network operator to optimize network performance, the goal is to migrate the optical flow from the initial light-tree to the final light-tree without flow interruption. Flow interruption is not desirable for network operators because it forces them to pay financial penalties to their customers. To solve this problem, existing methods use a branch approach that is inefficient if some network nodes do not have wavelength conversion capability. Therefore, we proposed in this study a sub-tree-based method. This approach selects and configures sub-tree pairs from the light-tree pair (initial light-tree, final light-tree) to be reconfigured. Then, we produce a sequence of configurations. The performance study confirms that our method is efficient in solving the problem of light-tree pair reconfiguration because our method does not cause flow interruption.

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Switch Architecture with Wavelength Conversion in Optical Networks

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.474-476.1479 ◽

2011 ◽

Vol 474-476 ◽

pp. 1479-1482

Author(s):

Ning Zhang

Keyword(s):

Optical Networks ◽

Wavelength Division Multiplexing ◽

Wavelength Conversion ◽

Optical Network ◽

Full Potential ◽

Wdm Optical Networks ◽

Wavelength Converter ◽

Wavelength Division ◽

Wavelength Reuse ◽

Network Flexibility

In this paper, we analyze the optical network with wavelength conversion, and discuss the architecture of network with wavelength converter in its node. The optical cross connects technology for wavelength division multiplexing (WDM) is rapidly developing. Wavelength conversion is one of the key techniques for switch WDM optical networks. The wavelength conversion technology can achieve wavelength reuse, decrease wavelength competition, enhance network flexibility and scalability, and simplify network structure and management. The results show that If these cross-connectors feature integrated with wavelength conversion, network will be better able to play the full potential of WDM optical networks.

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Wavelength Converter Based Optimized RWA for All Optical Networks

Asian Journal of Computer Science and Technology ◽

10.51983/ajcst-2019.8.2.2131 ◽

2019 ◽

Vol 8 (2) ◽

pp. 111-115

Author(s):

Shilpa S. Patil ◽

Bharat S. Chaudhari

Keyword(s):

Optical Networks ◽

Network Performance ◽

Blocking Probability ◽

Wavelength Assignment ◽

Wdm Networks ◽

Optimal Placement ◽

Wavelength Converters ◽

Wavelength Converter ◽

Call Blocking ◽

Call Blocking Probability

Wavelength converters are used in WDM networks to avoid call blocking and minimizing the blocking probability. Optimal placement of wavelength converters restricts the call blocking probability, the complexity and improves the overall network performance of the network. In this paper, we propose a new weight dependent routing and wavelength assignment algorithm for the optimal placement of the wavelength converters. The wavelength converter placement was considered separately at all the nodes and the partial nodes. Our algorithm outperforms the previously reported studies and requires a lesser number of wavelength converters to achieve the required performance. It reduces the blocking probabilities up to 5.4% and shows that the first four nodes primarily control the blocking performance of the network. The study also reveals that instead of merely increasing the number of converters, their placement at the right location plays a crucial role in improving the performance. Initially, although an increase in the number of the wavelengths also improves the network performance, the further increase does not contribute much to the reduction of the blocking probability.

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Placement of Wavelength Converters in Dynamically Routed All Optical Networks in presence of Tunable Transceivers

Network Protocols and Algorithms ◽

10.5296/npa.v7i4.8567 ◽

2016 ◽

Vol 7 (4) ◽

pp. 26

Author(s):

Shilpa S Patil ◽

Bharat S Chaudhari

Keyword(s):

Performance Analysis ◽

Optical Networks ◽

Network Performance ◽

Blocking Probability ◽

Wavelength Converters ◽

Wavelength Converter ◽

Challenging Tasks ◽

All Optical ◽

Continuity Constraint ◽

The Cost

Efficient routing with optimal resources is one of the challenging tasks in the design of DWDM networks. Wavelength Converter (WC) is an important resource, as the placement of WCs affects the network performance and the quantity of WCs affects the cost of the network. With the help of WCs the network performance can be maximized by removing the wavelength continuity constraint. As WCs are very expensive, selecting the candidate nodes for the placement of WCs in a network is important. In this paper we have proposed an optimized approach for the placement of WCs in the presence of tunable transceivers (TTRs) and fixed transceivers (FTRs). The performance analysis has been carried out for above approaches. Observation shows that sparse partial wavelength converters with various loads requires only 2.4% converters. When tunable transceivers are used an average reduction of 73% in blocking probability and average saving of 91% in required number of converters.

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A Deeply Saturated Differentially-Biased SOA-MZI for 20 Gb/s Burst-Mode NRZ Traffic

Applied Sciences ◽

10.3390/app9152971 ◽

2019 ◽

Vol 9 (15) ◽

pp. 2971

Author(s):

Apostolos Tsakyridis ◽

Miltiadis Moralis-Pegios ◽

Christos Vagionas ◽

Eugenio Ruggeri ◽

George Kalfas ◽

...

Keyword(s):

Optical Networks ◽

Peak Power ◽

Wavelength Conversion ◽

State Of The Art ◽

Optical Amplifier ◽

Wavelength Converter ◽

Active Components ◽

Transmission Experiment ◽

Burst Mode ◽

Power Equalization

We experimentally demonstrate an optical Burst-Mode Wavelength Converter (BMWC) that simultaneously provides power equalization and wavelength conversion of Non-Return to Zero-On/Off Keying (NRZ-OOK) data and operates up to 20 Gb/s. It employs a balanced, differentially-biased, Semiconductor Optical Amplifier-Mach Zehnder Interferometer (SOA-MZI) operating in deeply saturated regime and its performance is evaluated at 10 Gb/s and 20 Gb/s with loud/soft peak–power ratios up to 9 dB and 5 dB, respectively. Bit Error Rate (BER) measurements reveal error free operation with up to 6.1 dB BER improvement at 10 Gb/s and 3.51 dB at 20 Gb/s, while the use of a single SOA-MZI yields 50% reduction in the number of active components against state-of-the-art BMWCs. Finally, the proposed BMWC is evaluated in non-dispersion compensated 25 km fiber transmission experiment, providing error-free operation with 1.43 dB BER improvement, validating its capabilities for potential employment in Passive Optical Networks (PON) and 5G fronthaul networks.

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Broad-Range tunable optical wavelength converter for next generation optical superchannels

DYNA ◽

10.15446/dyna.v82n194.45521 ◽

2015 ◽

Vol 82 (194) ◽

pp. 72-78

Author(s):

Andrés Felipe Betancur Pérez ◽

Ana María Cárdenas Soto ◽

Neil Guerrero González

Keyword(s):

Optical Networks ◽

Wavelength Conversion ◽

Wavelength Converter ◽

Channel Spacing ◽

Optical Wavelength ◽

All Optical ◽

Signal Demodulation ◽

Optical Wavelength Converter ◽

Optical Wavelength Conversion ◽

Conversion Scheme

A broad-range tunable all optical wavelength conversion scheme that is based on a dual driven Mach-Zehnder modulator with an integrated microwave generator to tune the channel spacing along the entire C band, is proposed. Successful signal demodulation up to 8 wavelength conversions, in steps of 50-400 GHz of 100 Gbps Nyquist QPSK channels with configurable channel spacing is reported. The proposed wavelength conversion scheme enables flexible wavelength routing on gridless optical networks, as can be seen in the Superchannels with a BER lower than 10<sup>-13</sup>.

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COORDINATED DISTRIBUTED SCHEDULING IN WIRELESS MESH NETWORK

INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY ◽

10.24297/ijct.v3i3a.2940 ◽

2012 ◽

Vol 3 (3) ◽

pp. 368-374

Author(s):

Usha Kumari ◽

Udai Shankar

Keyword(s):

Network Performance ◽

Mesh Networks ◽

Mac Protocol ◽

Scheduling Algorithm ◽

Ieee 802.16 ◽

Distributed Scheduling ◽

Mesh Network ◽

Fourth Generation ◽

Network Nodes ◽

Wireless Mesh

IEEE 802.16 based wireless mesh networks (WMNs) are a promising broadband access solution to support flexibility, cost effectiveness and fast deployment of the fourth generation infrastructure based wireless networks. Reducing the time for channel establishment is critical for low latency/interactive Applications. According to IEEE 802.16 MAC protocol, there are three scheduling algorithms for assigning TDMA slots to each network node: centralized and distributed the distributed is further divided into two operational modes coordinated distributed and uncoordinated distributed. In coordinated distributed scheduling algorithm, network nodes have to transmit scheduling message in order to inform other nodes about their transfer schedule. In this paper a new approach is proposed to improve coordinated distributed scheduling efficiency in IEEE 802.16 mesh mode, with respect to three parameter Throughput, Average end to end delay and Normalized Overhead. For evaluating the proposed networks efficiency, several extensive simulations are performed in various network configurations and the most important system parameters which affect the network performance are analyzed

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Exploring a New Adaptive Routing Based on the Dijkstra Algorithm in Optical Networks-on-Chip

Micromachines ◽

10.3390/mi12010054 ◽

2021 ◽

Vol 12 (1) ◽

pp. 54

Author(s):

Yan-Li Zheng ◽

Ting-Ting Song ◽

Jun-Xiong Chai ◽

Xiao-Ping Yang ◽

Meng-Meng Yu ◽

...

Keyword(s):

Power Consumption ◽

Power Control ◽

Optical Networks ◽

Output Power ◽

Network Performance ◽

Transmission Loss ◽

Adaptive Routing ◽

Dijkstra Algorithm ◽

Networks On Chip ◽

On Chip

The photoelectric hybrid network has been proposed to achieve the ultrahigh bandwidth, lower delay, and less power consumption for chip multiprocessor (CMP) systems. However, a large number of optical elements used in optical networks-on-chip (ONoCs) generate high transmission loss which will influence network performance severely and increase power consumption. In this paper, the Dijkstra algorithm is adopted to realize adaptive routing with minimum transmission loss of link and reduce the output power of the link transmitter in mesh-based ONoCs. The numerical simulation results demonstrate that the transmission loss of a link in optimized power control based on the Dijkstra algorithm could be maximally reduced compared with traditional power control based on the dimensional routing algorithm. Additionally, it has a greater advantage in saving the average output power of optical transmitter compared to the adaptive power control in previous studies, while the network size expands. With the aid of simulation software OPNET, the network performance simulations in an optimized network revealed that the end-to-end (ETE) latency and throughput are not vastly reduced in regard to a traditional network. Hence, the optimized power control proposed in this paper can greatly reduce the power consumption of s network without having a big impact on network performance.

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A Joint Multicast Optimization Approach for QoS Provisioning in Optical Label Switching (OLS) Networks

Journal of Optical Communications ◽

10.1515/joc-2018-0169 ◽

2019 ◽

Vol 0 (0) ◽

Author(s):

Yassine Khlifi ◽

Majid Alotaibi

Keyword(s):

Traffic Management ◽

Network Performance ◽

Data Transfer ◽

Optimization Approach ◽

Optimization Strategy ◽

Wavelength Converter ◽

Label Switching ◽

Link Capacity ◽

Two Stages ◽

Logical Topology

AbstractOptical label switching is introduced for ensuring fast data transfer, quality of service (QoS) support, and better resource management. However, the important issue is how to optimize resource usage and satisfy traffic constraints for improving network performance and design. This paper proposes a dynamic approach that optimizes the resource in terms of link capacity and FDL (fiber delay line) buffering as well as a wavelength converter. The proposed approach decreases the resources usage and guarantees QoS support for various traffic demands. The optimization strategy consists of two stages: path building and traffic management. The path building assures logical topology making using the cumulative cost of available resource and traffic requirements including unicast and multicast. The traffic management solves the resource formulation problem during the traffic transfer by guaranteeing the required loss and blocking delay. Simulation work is conducted for validating the proposed approach and evaluating its performances and effectiveness. Simulation results show that our proposal minimizes effectively the use of link capacity of lightpath and light-tree. Moreover, our approach optimizes the use of buffering capacity and wavelength converter and guarantees QoS support according to traffic requirements.

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