Dynamic Wavelength And Bandwidth Allocation Research Articles

Fuzzy logic based dynamic wavelength and bandwidth allocation for 5G front haul networks

The Quality of Service (QoS) requirements for 5G are very strict in terms of latency of Fifth Generation (5G) traffic. 5G fronthaul networks between the baseband unit and remote radio heads are planned to use Next Generation - Passive Optical Networks 2 (NG-PON2) to carry their traffic. However, these Time Wavelength Division Multiplexing (TWDM) PON based networks also provide service to other traffic such as residential and corporate users. Therefore, it is crucial to provide QoS guarantees to 5G traffic. The main issue includes allocating transmission over multiple wavelengths while maintaining QoS. Although using all the available wavelengths all the time may seem to be the simple solution, each active wavelength increases the cost of operation. To solve these issues, this paper proposes a technique using fuzzy logic to dynamically allocate wavelength and bandwidth for 5G fronthaul networks. Two types of traffic, i.e., 5G traffic and normal traffic are considered while the problem of Dynamic Wavelength and Bandwidth Allocation (DWBA) is formulated as a queueing theory problem using penalties and a cost function. Penalties are assigned for waiting packets as well as each active wavelength. Then, modeling the number of active wavelengths, the number of packets in the system, the total cost, and the traffic intensity as input fuzzy variables while modeling the change in the number of active wavelengths as the fuzzy output variable. The Mamdani implication is used for the fuzzy inference engine and the height method is used for defuzzification of the output variable. Simulations in MATLAB show that the proposed technique can maintain the latency of 5G traffic lower than the defined threshold while also significantly reducing the number of active wavelengths. A comparison with the existing state-of-the-art techniques shows that the proposed technique results in an improvement of at least 46% and 29% in terms of the average number of active wavelengths and the average latency for 5G traffic, respectively.

High Bandwidth Utilization DWBA Algorithm for Upstream Channel in NG-EPON

In this paper, an (ONU-load and RTTs)-based (OLR) dynamic wavelength and bandwidth allocation (DWBA) algorithm for upstream channel in next-generational Ethernet passive optical network (NG-EPON) is proposed. By proposing adaptive threshold grouping algorithm, the waste of bandwidth resources caused by massive guard timeslots and mismatch between assigned transmission window and frame size is reduced. By adjusting the Optical Network Unit (ONU) scheduling order, the idle time caused by Round-Trip Times (RTTs) is reduced. By proposing joint ONU grouping and RTT scheduling mechanism, load balance among wavelengths is achieved. By proposing a fair allocation scheme, the fairness of bandwidth granting for each ONU is ensured. Finally, by the simulation, the effectiveness of proposed algorithm is demonstrated. The simulation indicates that the rate of bandwidth utilization, the average package delay, the scheduling cycle and the network throughput in the system based on proposed algorithm have better performance.

Fair and efficient DWBA algorithm based on SLA differentiated polling interleaved scheduling for NG-EPON

This study, based on the Next Generation Ethernet Passive Optical Network (NG-EPON) facing more complex and changeable network, develops a flexible and efficient resource allocation algorithm. First, a differentiated polling interleaved scheduling (DPIS) framework is designed based on dynamic awareness, significantly reducing idle time slots, improving channel upstream utilization, and performing service-level-agreement (SLA) support and Optical Network Unit (ONU) overall scheduling. Subsequently, a dynamic wavelength and bandwidth allocation (DWBA) scheme is presented, which allocates fair bandwidth between and in subcycles and ensures the timely transmission of large traffic ONUs. As revealed from the simulation results, the developed DPIS-DWBA algorithm exhibits high utilization and low latency performance of the online scheduling algorithm; it can also achieve the offline scheduling to support SLA and fairness and offers more effective delay differentiation and bandwidth fair service.

Dynamic wavelength and bandwidth allocation for supporting diverse customers and prioritized traffic in NG-PON2 networks

Resource allocation is a fundamental task in any PON and it is necessary to have an efficient scheme that reduces delay, maximizes bandwidth usage, and minimizes the resource wastage. A variety of dynamic bandwidth allocation (DBA) and dynamic wavelength and bandwidth allocation (DWBA) algorithms have been proposed which are based on different PONs (e.g., EPON, GPON, XG-PON, 10G EPON, etc.). But to our knowledge, no DWBA scheme for NG-PON2 system, with diverse customers and prioritized traffic, has been proposed yet. In this work, this problem is addressed and five different dynamic wavelength and bandwidth allocation (DWBA) schemes are proposed. First, mixed integer linear programming (MILP) models are developed to minimize the total delay of the high-priority data. Due to the MILP’s high computational complexity, heuristic algorithms are developed based on the MILP model insights. The five heuristic algorithms are: No Block-Split Heuristic (NBH), Equal Block-Split Heuristic (EBH), Priority-Based No Block-Split Heuristic (P-NBH), Priority-Based Equal Block-Split Heuristic (P-EBH), and Priority-Based Decider Block-Split Heuristic (P-DBH). Six priority classes of requests are introduced with the goal of minimizing the total delay for the high-priority data and to lessen the bandwidth wastage of the system. Finally, experiments for the performance evaluation of the five DWBA schemes are conducted. The results indicate that P-NBH, P-EBH, P-DBH schemes show a 47.63% less delay and 30% of less bandwidth wastage on average for the highest priority data transmission than the schemes without priority support (NBH and EBH). Among these five schemes, NBH method has the highest delay, whereas EBH and P-EBH waste more bandwidth than the other schemes. P-DBH is the most efficient among the five, because this scheme offers the lowest delay for high-priority data and the minimum bandwidth wastage for lower priority ones.

Bandwidth Utilization and Management Algorithms (BUMAs) for NG-EPON

An upcoming capable technology named as Next generation Ethernet passive optical network (NG-EPON); to handle enormous bandwidth and effective distribution requirements for prospective Internet based services. Standardization procedures for NG-EPON are in progress. Transmission of data traffic from Optical Network Units (ONUs) towards Optical Line Terminal (OLT) in NG-EPON is carried out through four wavelengths each operating at a data rate of 25Gbps. Dynamic wavelength and bandwidth allocation (DWBA) algorithms are needed for the efficient arbitration of the bandwidth resources between the subscribers. In this paper, we have proposed two different DWBA algorithms for NG-EPON; DWBA-I and DWBA-II. DWBA-I is a Quality-of-Service based algorithm that has been designed to manage the different types of data traffic in NG-EPON. DWBA-I performs better than the different existing DBA algorithms in terms of packet delay, completion time and packet drop ratio. DWBA-II is an algorithm designed to meet the system requirement specifications of NG-EPON and handle traffic requirements of subscribers in a cost effective manner. DWBA-II algorithm is comparatively analyzed and evaluated with First-Fit-DWBA and Modified-IPACT algorithms. Performance of DWBA-II is better on the basis of average delay, grant utilization, completion time and packets drop ratio. Performance of DWBA-I and DWBA-II has been evaluated through simulation results.

A learning algorithm for TWDM-PON’ DWBA with 5G fronthaul networks

Abstract Time and wavelength-division multiplexed passive optical network (TWDM-PON) is expected to be the fronthaul networks of 5G, which requires low latency and large bandwidth. In this paper, we propose a Q-learning based dynamic wavelength and bandwidth allocation (DWBA) algorithm for TWDM-PON. Simulation results show that the proposed DWBA algorithm can reduce the number of active channels by 40% and provide larger bandwidth with same wavelength number in comparation with the existing algorithms while satisfying the latency requirement of 5G fronthaul networks.

Dynamic bandwidth allocation algorithms for improved throughput and latency performance in CDMA-based next-generation ethernet passive optical networks

In this paper, we propose new scheduling algorithms to improve the performance of the code division multiple access (CDMA) enabled next generation ethernet passive optical networks (NG-EPON). The original dynamic bandwidth allocation (DBA) scheme based on a round robin scheduling algorithm was originally proposed for the first generation CDMA based EPON where the network throughput and delay requirements per optical network unit (ONU) are relatively moderate. On the other hand, in the NG-EPON standard, the network capacity is increased up to 100 Gb/s and stringent requirements are applied to the packet delay. For this reason, in this work, we propose new scheduling algorithms for NG-EPON to assign a grant size on each upstream CDMA code in order to guarantee the newly required network throughput and delay performance. The first DBA algorithm is the first in first out (FIFO) algorithm in which the ONU requests are ordered in terms of their request arrival time. The second scheme is the reservation pattern (RP) algorithm in which each ONU starts transmitting its queue content in its reserved pattern of subcycles following a pre-defined pattern. The performances of the newly proposed algorithms are evaluated and compared. Results show that both newly proposed scheduling schemes can significantly improve the network performance in terms of the packet delay, jitter, and throughput. In addition, the results are compared to many dynamic wavelength and bandwidth allocation (DWBA) algorithms. The results show that the performances are comparable and that CDMA can be a good alternative for WDM for multi-channels based NG-EPON.

Resource Management in Cloud and Tactile-Capable Next-Generation Optical Access Networks

This paper introduces OCLDN, an agile, programmable, and scalable optical cloud distribution network, which exploits content distribution networks to deliver killer cloud and tactile services to end users at very high speeds, ultra-low latency, and low cost. With OCLDN, a software-defined-networking-based mini-cloud data center is installed at the central office of a next-generation passive optical network, which includes a cloud-based tactile steering server, and supports all types of cloud applications. These applications have stringent quality-of-service (QoS) requirements and, thus, require a fast, adaptive, and effective bandwidth allocation mechanism. Therefore, in this paper, we introduce a new dynamic wavelength and bandwidth allocation (DWBA) scheme that meets the QoS requirements of tactile services via dedicating it upstream wavelength(s), and also enables inter-channel statistical multiplexing so as to maximize the network throughput without impairing the QoS requirements for all types of services. Extensive simulations demonstrate the ability of the proposed DWBA to outperform existing schemes, and highlight its effectiveness in meeting the QoS demands for tactile and non-tactile services.

On the efficiency and fairness of dynamic wavelength and bandwidth allocation algorithms for scheduling multi-type ONUs in NG-EPON

Abstract In the Next Generation Ethernet Passive Optical Network (NG-EPON), Optical Network Units (ONUs) can work on multiple wavelengths simultaneously to achieve higher peak rates. There are three types of ONUs (25G, 50G and 100G ONUs) sharing all the 100 Gb/s bandwidth. Each type of ONUs has a total bandwidth constraint due to ONUs’ working wavelength capabilities. In this paper, we investigate the fairness and efficiency of dynamic wavelength and bandwidth allocation (DWBA) algorithms for scheduling multi-type ONUs while considering their bandwidth capacity constraints. Proposed DWBA algorithms can achieve high efficiency, excellent fairness as well as good wavelength load balancing.

Dynamic Wavelength and Bandwidth Allocation Algorithms for Mitigating Frame Reordering in NG-EPON

The IEEE initialized a working group to study the 100 Gb/s next-generation passive optical networks (NG-EPON). A key technology adopted by NG-EPON is channel bonding, which enables optical network units (ONUs) to transmit data on multiple wavelength channels simultaneously to achieve higher peak rates. In the upstream, ONUs share the bandwidth of each wavelength in a time-division multiplexing manner, and dynamic wavelength and bandwidth allocation (DWBA) coordinates ONU upstream transmission. If an ONU is granted transmission of data on multiple wavelengths simultaneously, frame reordering will occur due to simultaneous parallel transmission, which needs to be minimized because buffer and extra processing time are needed to restore the original framesequence. For a group of ONUs, DWBA can grant each ONU transmission on either a single wavelength or multiple wavelengths without affecting total bandwidth occupation. Since ONUs transmitting on single wavelength can get rid of frame reordering, different DWBA algorithms can result in different numbers of ONUs suffering frame reordering. In this paper, we investigate the impacts of DWBA algorithms on frame reordering in NG-EPON. A DWBA algorithm for mitigating frame reordering without affecting bandwidth utilization is proposed. The theoretical upper bound of a frame-reordered ONU number with the proposed algorithm is also analyzed. The performances (in terms of frame-reordered ONU number and packet delay) of DWBA algorithms are evaluated through simulations. Simulation results show that the proposed algorithm can mitigate frame reordering efficiently and reduce packet delay as well.

Low-Latency Dynamic Wavelength and Bandwidth Allocation Algorithm for NG-EPON

Recently, the IEEE 802.3ca Task Force has been working to standardize the next-generation Ethernet passive optical network (NG-EPON) to fulfill future bandwidth demands. NG-EPON allows an optical network unit (ONU) transmission to be scheduled on multiple wavelength channels simultaneously. This will increase network capacity up to 100 Gb/s, along with flexibility, as any of the channels can be allocated from the four wavelength channels, each having a capacity of 25 Gb/s. However, it also raises many technical aspects to be considered while deciding on an optimum scheduling strategy for NG-EPON (100G-EPON) architecture. This paper proposes a dynamic wavelength and bandwidth allocation (DWBA) algorithm for NG-EPON to schedule upstream wavelength channels while providing a low average packet delay and catering frame resequencing problem. An online scheduling framework with gated service grant sizing policy has been demonstrated in this work. The proposed DWBA algorithm’s performance is evaluated in comparison with legacy interleaved polling with an adaptive cycle time (modified- IPACT) and recently proposed water-filling algorithmbased DWBA (WF-DBA) algorithms. Simulation results confirmed the validity of the proposed DWBA algorithm.

Energy-Efficient Framework for Time and Wavelength Division Multiplexed Passive Optical Networks

For the first time, to the best of our knowledge, an energy-efficient framework that optimizes the number of active wavelengths and uses sleep/doze mode to improve the energy savings of a delay-constrained time and wavelength division multiplexed passive optical network is presented in this work. In the proposed framework, the optical network units (ONUs) operate under the maximum polling cycle time that satisfies a given delay constraint to achieve maximum possible energy savings at the ONUs. When the average bandwidth requested by an ONU exceeds the maximumallowable bandwidth, a new wavelength is introduced to the network to satisfy delay constraints. Conversely, when the bandwidth requested by an ONU is small, idle wavelengths are switched off to increase energy savings at the optical line terminal (OLT). The proposed framework is analyzed using online and offline just-in-time dynamic wavelength and bandwidth allocation (DWBA) algorithms. The performance of both algorithms, under the proposed framework, is evaluated in terms of average delay, percentage of energy savings at the ONU, and percentage of energy savings at the OLT. Our analytical and simulation results indicate that under the proposed framework, the average delay of the network remains below a specified maximum allowable delay, in both algorithms. The online DWBA algorithm, however, results in improved energy savings, both at the OLT and at the ONUs, compared to the offline DWBA algorithm.

Dynamic Wavelength and Bandwidth Allocation in Flexible TWDM Optical Access Network

As one of the most promising next generation optical access network (OAN), flexible time and wavelength division multiplexing (TWDM) OAN can increase capacity smoothly and reallocate wavelength and timeslot resource dynamically to cope with variations in traffic pattern. However, the scheduling of both wavelength and timeslot resource becomes a critical problem. In this letter, a dynamic wavelength and bandwidth allocation (DWBA) solution including the DWBA mechanism, mixed integer linear programming (MILP) model, and two heuristic algorithms is proposed to solve the scheduling problem. By comparison of the two algorithms, only one algorithm is selected to support 10-year lifetime. Under different traffic patterns, the selected DWBA algorithm has better bandwidth utilization and lower delay in contrast with the static wavelength allocation (SWA). The backward compatibility and cost efficiency of flexible TWDM OAN are also discussed.