| 1. |
- Wang, Kun
(författare)
-
Migration Towards Next Generation Optical Access and Transport Networks
- 2017
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- By 2020 there will be 50 billion connected devices over the Internet. With the fast-increasing data traffic demand in both fixed and mobile networks, network operators need to migrate networks towards next generation solutions. The network migration requires the enormous investment in equipment and infrastructure, while the revenues are not expected to grow significantly. Therefore, one of the main challenges for network operators is to find out a proper cost-effective optical network solution that can match future high capacity demand and flexibly support multiple network services on a common network infrastructure.The first part of the thesis addresses the Active Optical Network (AON) and its migration strategies towards Next Generation Optical Access (NGOA) solutions. Several migration strategies are proposed from the perspective of network topology, data plane and control plane. A general methodology for Techno-Economic analysis has been developed and applied to the Total Cost of Ownership (TCO) calculation of different NGOA solutions. The thesis provides a complete cost evaluation of AON migration paths, which can be used by network operators to assess the economic feasibility of network migration.A converged Optical Transport Network (OTN) that can serve both fixed and mobile network services is beneficial from the cost-saving perspective. However, the different types of services, require different network performance. The second part of the thesis focuses on the investigation of the converged OTN that can be flexibly and timely adjusted to satisfy varying service conditions. A programmable OTN featured with Wavelength Division Multiplexing (WDM) in the data plane and Software Defined Networking (SDN) in control plane has been proposed. To demonstrate the benefits of the converged OTN, the thesis also provides a multi-domain orchestration architecture for the multiple network services. The resource orchestration, across three network domains: OTN, mobile network and cloud, enables agile service creation and optimized resource allocation among the multiple domains.
|
|
| 2. |
- Jirattigalachote, Amornrat, 1982-
(författare)
-
Provisioning Strategies for Transparent Optical Networks Considering Transmission Quality, Security, and Energy Efficiency
- 2012
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The continuous growth of traffic demand driven by the brisk increase in number of Internet users and emerging online services creates new challenges for communication networks. The latest advances in Wavelength Division Multiplexing (WDM) technology make it possible to build Transparent Optical Networks (TONs) which are expected to be able to satisfy this rapidly growing capacity demand. Moreover, with the ability of TONs to transparently carry the optical signal from source to destination, electronic processing of the tremendous amount of data can be avoided and optical-to-electrical-to-optical (O/E/O) conversion at intermediate nodes can be eliminated. Consequently, transparent WDM networks consume relatively low power, compared to their electronic-based IP network counterpart. Furthermore, TONs bring also additional benefits in terms of bit rate, signal format, and protocol transparency. However, the absence of O/E/O processing at intermediate nodes in TONs has also some drawbacks. Without regeneration, the quality of the optical signal transmitted from a source to a destination might be degraded due to the effect of physical-layer impairments induced by the transmission through optical fibers and network components. For this reason, routing approaches specifically tailored to account for the effect of physical-layer impairments are needed to avoid setting up connections that don’t satisfy required signal quality at the receiver. Transparency also makes TONs highly vulnerable to deliberate physical-layer attacks. Malicious attacking signals can cause a severe impact on the traffic and for this reason proactive mechanisms, e.g., network design strategies, able to limit their effect are required. Finally, even though energy consumption of transparent WDM networks is lower than in the case of networks processing the traffic at the nodes in the electronic domain, they have the potential to consume even less power. This can be accomplished by targeting the inefficiencies of the current provisioning strategies applied in WDM networks.The work in this thesis addresses the three important aspects mentioned above. In particular, this thesis focuses on routing and wavelength assignment (RWA) strategies specifically devised to target: (i) the lightpath transmission quality, (ii) the network security (i.e., in terms of vulnerability to physical-layer attacks), and (iii) the reduction of the network energy consumption. Our contributions are summarized below.A number of Impairment Constraint Based Routing (ICBR) algorithms have been proposed in the literature to consider physical-layer impairments during the connection provisioning phase. Their objective is to prevent the selection of optical connections (referred to as lightpaths) with poor signal quality. These ICBR approaches always assign each connection request the least impaired lightpath and support only a single threshold of transmission quality, used for all connection requests. However, next generation networks are expected to support a variety of services with disparate requirements for transmission quality. To address this issue, in this thesis we propose an ICBR algorithm supporting differentiation of services at the Bit Error Rate (BER) level, referred to as ICBR-Diff. Our approach takes into account the effect of physical-layer impairments during the connection provisioning phase where various BER thresholds are considered for accepting/blocking connection requests, depending on the signal quality requirements of the connection requests. We tested the proposed ICBR-Diff approach in different network scenarios, including also a fiber heterogeneity. It is shown that it can achieve a significant improvement of network performance in terms of connection blocking, compared to previously published non-differentiated RWA and ICBR algorithms. Another important challenge to be considered in TONs is their vulnerability to physical-layer attacks. Deliberate attacking signals, e.g., high-power jamming, can cause severe service disruption or even service denial, due to their ability to propagate in the network. Detecting and locating the source of such attacks is difficult, since monitoring must be done in the optical domain, and it is also very expensive. Several attack-aware RWA algorithms have been proposed in the literature to proactively reduce the disruption caused by high-power jamming attacks. However, even with attack-aware network planning mechanisms, the uncontrollable propagation of the attack still remains an issue. To address this problem, we propose the use of power equalizers inside the network nodes in order to limit the propagation of high-power jamming attacks. Because of the high cost of such equipment, we develop a series of heuristics (incl. Greedy Randomized Adaptive Search Procedure (GRASP)) aiming at minimizing the number of power equalizers needed to reduce the network attack vulnerability to a desired level by optimizing the location of the equalizers. Our simulation results show that the equalizer placement obtained by the proposed GRASP approach allows for 50% reduction of the sites with the power equalizers while offering the same level of attack propagation limitation as it is possible to achieve with all nodes having this additional equipment installed. In turn, this potentially yields a significant cost saving. Energy consumption in TONs has been the target of several studies focusing on the energy-aware and survivable network design problem for both dedicated and shared path protection. However, survivability and energy efficiency in a dynamic provisioning scenario has not been addressed. To fill this gap, in this thesis we focus on the power consumption of survivable WDM network with dynamically provisioned 1:1 dedicated path protected connections. We first investigate the potential energy savings that are achievable by setting all unused protection resources into a lower-power, stand-by state (or sleep mode) during normal network operations. It is shown that in this way the network power consumption can be significantly reduced. Thus, to optimize the energy savings, we propose and evaluate a series of energy-efficient strategies, specifically tailored around the sleep mode functionality. The performance evaluation results reveal the existence of a trade-off between energy saving and connection blocking. Nonetheless, they also show that with the right provisioning strategy it is possible to save a considerable amount of energy with a negligible impact on the connection blocking probability.In order to evaluate the performance of our proposed ICBR-Diff and energy-aware RWA algorithms, we develop two custom-made discrete-event simulators. In addition, the Matlab program of GRASP approach for power equalization placement problem is implemented.
|
|
| 3. |
- Muhammad, Ajmal
(författare)
-
Planning and Provisioning Strategies for Optical Core Networks
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Optical communication networks are considered the main catalyst for the transformation of communication technology, and serve as the backbone of today's Internet. The inclusion of exciting technologies, such as, optical amplifiers, wavelength division multiplexing (WDM), and reconfigurable optical add/drop multiplexers (ROADM) in optical networks have made the cost of information transmission around the world negligible. However, to maintain the cost effectiveness for the growing bandwidth demand, facilitate faster provisioning, and provide richer sets of service functionality, optical networks must continue to evolve. With the proliferation of cloud computing the demand for a promptly responsive network has increased. Moreover, there are several applications, such as, real time multimedia services that can become realizable, depending on the achievable connection set-up time.Given the high bandwidth requirements and strict service level specifications (SLSs) of such applications, dynamic on-demand WDM networks are advocated as a first step in this evolution. SLSs are metrics of a service level agreement (SLA), which is a contract between a customer and network operator. Apart from the other candidate parameters, the set-up delay tolerance, and connection holding-time have been defined as metrics of SLA. Exploiting these SLA parameters for on-line provisioning strategies exhibits a good potential in improving the overall network blocking performance. However, in a scenario where connection requests are grouped in different service classes, the provisioning success rate might be unbalanced towards those connection requests with less stringent requirements, i.e., not all the connection requests are treated in a fair way.The first part of this thesis focuses on different scheduling strategies for promoting the requests belonging to smaller set-up delay tolerance service classes. The first part also addresses the problem of how to guarantee the signal quality and the fair provisioning of different service classes, where each class corresponds to a specified target of quality of transmission. Furthermore, for delay impatient applications the thesis proposes a provisioning approach, which employs the possibility to tolerate a slight degradation in quality of transmission during a small fraction of the holding-time.The next essential phase for scaling system capacity and satisfying the diverse customer demands is the introduction of flexibility in the underlying technology. In this context, the new optical transport networks, namely elastic optical networks (EON) are considered as a worthwhile solution to efficiently utilize the available spectrum resources. Similarly, space division multiplexing (SDM) is envisaged as a promising technology for the capacity expansion of future networks. Among the alternative for flexible nodes, the architecture on demand (AoD) node has the capability to dynamically adapt its composition according to the switching and processing needs of the network traffic.The second part of this thesis investigates the benefits of set-up delay tolerance for EON by proposing an optimization model for dynamic and concurrent connection provisioning. Furthermore, it also examines the planning aspect for flexible networks by presenting strategies that employ the adaptability inherent in AoD. Significant reduction in switching devices is attainable by proper planning schemes that synthesized the network by allocating switching device where and when needed while maximizing fiber switching operation. In addition, such a design approach also reduces the power consumption of the network. However, cost-efficient techniques in dynamic networks can deteriorate the network blocking probability owing to insufficient number of switching modules. For dynamic networks, the thesis proposes an effective synthesis provisioning scheme along with a technique for optimal placement of switching devices in the network nodes.The network planning problem is further extended to multi-core-fiber (MCF) based SDM networks. The proposed strategies for SDM networks aim to establish the connections through proper allocation of spectrum and core while efficiently utilizing the spectrum resources. Finally, the optimal planning strategy for SDM networks is tailored to fit synthetic AoD based networks with the goal to optimally build each node and synthesize the whole network with minimum possible switching resources.
|
|
| 4. |
- Cheng, Yuxin
(författare)
-
Optical Interconnects for Next Generation Data Centers : Architecture Design and Resource Allocation
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The current data center architectures based on blade servers and elec- tronic packet switches face several problems, e.g., limited resource utilization, high power consumption and cost, when handling the rapidly growing of data traffic. Optical networks offering ultra-high capacity and requiring low energy consumption are considered as a good option to address these problems. This thesis presents new data center architectures based on optical interconnects and transmissions, and evaluates performance by extensive simulations.The first main contribution of the thesis is to introduce a passive optical top-of-rack interconnect (POTORI) architecture. The data plane of POTORI mainly consists of passive components to interconnect the servers within the rack. Using the passive components makes it possible to significantly reduce power consumption while achieving high reliability in a cost-efficient way. In addition, the POTORI’s control plane is based on a centralized controller, which is responsible for coordinating the communications among the servers in the rack. A cycle-based medium access control (MAC) protocol and a dy- namic bandwidth allocation (DBA) algorithm are designed for the POTORI to efficiently manage the exchange of control messages and the data transmis- sion inside the rack. Simulation results show that under realistic DC traffic scenarios, the POTORI with the proposed DBA algorithm is able to achieve an average packet delay below 10 μs with the use of fast tunable optical transceivers.The second main contribution of the thesis is to investigate rack-scale disaggregated data center (DDC) architecture for improving resource utiliza- tion. In contrast to the traditional DC with blade servers that integrate various types of resources (e.g., central processing unit (CPU), memory) in a chassis, the rack-scale DDC contains fully decoupled resources held on differ- ent blades, referred to as resource blades. The resource blades are required to be interconnected within the rack by an ultra-high bandwidth optical in- terconnect through the optical interfaces (OIs). A resource allocation (RA) algorithm is proposed to efficiently schedule the resources in the DDC for virtual machine requests. Results show that with sufficient bandwidth on the OIs, the rack-scale DDC with the proposed RA algorithm can achieve 20% higher resource utilization and make 30% more revenue comparing to the traditional DC.
|
|
| 5. |
- Cheng, Yuxin
(författare)
-
Passive Optical Top-of-Rack Interconnect for Data Center Networks
- 2017
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Optical networks offering ultra-high capacity and low energy consumption per bit are considered as a good option to handle the rapidly growing traffic volume inside data center (DCs). However, most of the optical interconnect architectures proposed for DCs so far are mainly focused on the aggregation/core tiers of the data center networks (DCNs), while relying on the conventional top-of-rack (ToR) electronic packet switches (EPS) in the access tier. A large number of ToR switches in the current DCNs brings serious scalability limitations due to high cost and power consumption. Thus, it is important to investigate and evaluate new optical interconnects tailored for the access tier of the DCNs.We propose and evaluate a passive optical ToR interconnect (POTORI) architecture for the access tier. The data plane of the POTORI consists mainly of passive components to interconnect the servers within the rack as well as the interfaces toward the aggregation/core tiers. Using the passive components makes it possible to significantly reduce power consumption while achieving high reliability in a cost-efficient way.Meanwhile, our proposed POTORI’s control plane is based on a centralized rack controller, which is responsible for coordinating the communications among the servers in the rack. It can be reconfigured by software-defined networking (SDN) operation. A cycle-based medium access control (MAC) protocol and a dynamic bandwidth allocation (DBA) algorithm are designed for the POTORI to efficiently manage the exchange of control messages and the data transmission inside the rack.Simulation results show that under realistic DC traffic scenarios, the POTORI with the proposed DBA algorithm is able to achieve an average packet delay below 10 μs with the use of fast tunable optical transceivers. Moreover, we further quantify the impact of different network configuration parameters on the average packet delay.
|
|
| 6. |
- Lin, Rui
(författare)
-
High-capacity short-reach optical communications
- 2016
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The global traffic is experiencing an exponential growth posing severe challenges to the communication networks in terms of capacity. As a future-proof technology fiber communication is widely implemented in different network segments, which can be categorized by transmission distance as long-haul and short-reach. This thesis focuses on the short-reach communication networks including fiber access network connecting the end users to the metro/core networks that covering tens of kilometers and optical datacenter network handling the traffic within the datacenter with distance up to a few kilometers. For fiber access networks, wavelength division multiplexing passive optical networks (WDM-PONs) assign a dedicated wavelength channel to each user guaranteeing high data rate. Dense channels enlarges the user count but makes the signals vulnerable to the wavelength drift. In this regard we propose two schemes based on optical frequency comb technique to generate stable carriers for WDM-PONs. Meanwhile, radio-over-fiber techniques allows the transmission of radio signals between central offices and the cells. Millimeter wave (MMW) over fiber, on the other hand, offer high bandwidth for future high capacity mobile access. We propose and experimentally demonstrate a palm-shaped spectrum generation where the high-power central carrier can be used for upstream transmission while multiple MMW bands are capable of transmitting different downstream data simultaneously. Regarding optical datacenter networks, passive optical interconnects (POIs) have been proposed as an energy-efficient solution since only passive optical components are used for server interconnection. However, the high insertion loss may result in a scalability problem. We develop a methodology that considers various physical-layer aspects, e.g., receiver types, modulation formats, to quantify the scalability of POIs. Both theoretical analyses and experimental measurements have been performed to assess the scalability of various coupler-based POIs.
|
|
| 7. |
- Mahloo, Mozhgan, 1983-
(författare)
-
Transport Solutions for Future Broadband Access Networks
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- “Connected society” where everything and everyone are connected at any time and on any location brings new challenges for the network operators. This leads to the need of upgrading the transport networks as the segment of Internet infrastructure connecting the fixed users and mobile base stations to the core/aggregation in order to provide high sustainable bandwidth, as well as supporting a massive number of connected devices. To do this, operators need to change the way that access networks are currently deployed. The future access network technologies will need to support very high capacity and very long distances, which are the inherited characteristics of optical transmission. Hence, optical fiber technology is recognized as the only future proof technology for broadband access.Capacity upgrade in the access networks can lead to a huge capacity demand in the backbone network. One promising solution to address this problem, is to keep the local traffic close to the end users as much as possible, and prevent unnecessary propagation of this type of traffic through the backbone. In this way, operators would be able to expand their access network without the significant capacity upgrade in the higher aggregation layers. Motivated by this need, a comprehensive evaluation of optical access networks is carried out in this thesis regarding ability of accommodating local traffic and amount of possible saving in the backbone by implementing locality awareness schemes.Meanwhile, next generation optical access (NGOA) networks have to provide high capacity at low cost while fulfilling the increasing reliability requirements of future services and customers. Therefore, finding cost-efficient and reliable alternative for future broadband access is one of the most important contributions of this thesis. We analyzed the tradeoff between the cost needed to deploy backup resources and the reliability performance improvement obtained by the proposed protection mechanism.Among different NGOA architectures, hybrid time and wavelength division multiplexing passive optical network (TWDM PON) is considered as a proper candidate providing high capacity and large coverage. Therefore, this approach is further analyzed and several tailored protection schemes with high flexibility are proposed to statisfy different requirements from the residential and business users in the same PON. The work carried out in the thesis has proved that TWDM PON can also offer high reliability performance while keeping the network expenditures at an acceptable level. Considering some other advantages such as low power consumption and high flexibility in resource allocation of this architecture, it has high potential to be the best candidate for NGOA networks. Moreover, new deployments of radio access networks supporting the increasing capacity demand of mobile users lead to the upgrade of the backhaul segment as a part of broadband access infrastructure. Hence, this thesis also contributes with a comprehensive techno-economic evaluation methodology for mobile backhaul. Several technologies are investigated in order to find the most cost-efficient solution for backhauling the high capacity mobile networks. Finally, a PON-based mobile backhaul with high capacity and low latency has been proposed for handling coordinated multipoint transmission systems in order to achieve high quality of experience for mobile users.
|
|
| 8. |
- Muhammad, Ajmal
(författare)
-
Connections Provisioning Strategies for dynamic WDM networks
- 2012
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The size, complexity, and the amount of traffic generation of optical communication networks have dramatically increased over the last decades. Exciting technologies, namely, optical amplifiers, wavelength division multiplexing (WDM) and optical filters have been included in optical networks, in order to fulfill end users appetite for bandwidth. However, the users high bandwidth demand will further increase with time, as emerging on-demand bandwidth intensive applications are starting to dominate the networks. Applications such as interactive video, ultra-high definition TV, backup storage, grid computing, e-science, e-health to mention a few, are becoming increasingly attractive and important for the community. Given the high bandwidth requirements and strict service level specifications (SLSs) of such applications, WDM networks equipped with agile devices, such as reconfigurable optical add-drop multiplexers and tunable transceivers integrated with G-MPLS/ASON control-plane technology are advocated as a natural choice for their implementation. SLSs are metrics of a service level agreement (SLA), which is a contract between a customer and network operator. Apart from other candidate parameters, the set-up delay tolerance and connection holding-time have been defined as metrics of SLA.This work addresses the network connections provisioning problem for the above mentioned demanding applications, by exploiting the time dimension of connections request. The problem is investigated for dynamic networks comprising ideal and nonideal components in their physical layer, and for applications with differentiated set-up delay tolerance and quality of signal requirements. Various strategies for different scenarios are proposed, each strategy combining in a different way the concept of both set-up delay tolerance and connection holding-time awareness. The objectives of all these strategies are to enhance the network connections provisioning capability and to fulfill customers demand, by utilizing the network resources efficiently.
|
|
| 9. |
- Yaghoubi, Forough, 1988-
(författare)
-
Agile, Resilient and Cost-efficient Mobile Backhaul Networks
- 2017
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The exponentially increasing traffic demand for mobile services requires innovative solutions in both access and backhaul segments of 5th generation (5G) mobile networks. Although, heterogeneous networks (HetNets) are a promising solution for the wireless access, the backhaul segment has received considerably less attention and falls short in meeting the stringent requirements of 5G in terms of capacity and availability.HetNets together with mobility requirements motivate the use of microwave backhauling that supports fiber-like capacity with millimeter-wave communications. However, higher carrier frequencies are subject to weather disturbances like rain that may substantially degrade the network throughput. To mitigate this effect, we develop a fast and accurate rain detection algorithm that triggers a network-layer strategy, i.e., rerouting. The results show that with small detection error the network throughput increases while posing small overhead on the network.The rain impact can be alleviated by centralized rerouting under the software defined networking paradigm. However, careless reconfiguration may impose inconsistency that leads to a significant temporary congestion and limits the gain of rerouting. We propose a consistency-aware rerouting framework by considering the cost of reconfiguration. At each time, the centralized controller may either take a rerouting or no-rerouting decision in order to minimize the total data loss. We use a predictive control algorithm to provide such an online sequence of decisions. Compared to the regular rerouting, our proposed approach reduces the throughput loss and substantially decreases the number of reconfigurations.In the thesis we also study which backhaul option is the best from a techno-economic perspective. We develop a comprehensive framework to calculate the total cost of ownership of the backhaul segment and analyze the profitability in terms of cash flow and net present value. The results highlight the importance of selecting proper backhaul solution to increase profitability.
|
|
| 10. |
- Ahmed, Jawwad
(författare)
-
Dynamic Resource Provisioning and Survivability Strategies in Optical Networks
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Optical networks based on Wavelength Division Multiplexing (WDM) technology show many clear benefits in terms of high capacity, flexibility and low power consumption. All these benefits make WDM networks the preferred choice for today’s and future transports solutions which are strongly driven by a plethora of emerging online services.In such a scenario, capability to provide high capacity during the service provisioning phase is of course very important, but it is not the only requirement that plays a central role. Traffic dynamicity is another essential aspect to consider because in many scenarios, e.g., in the case of real time multimedia services, the connections are expected to be provisioned and torn down quickly and relatively frequently. High traffic dynamicity may put a strain on the network control and management operations (i.e., the overhead due to control message exchange can grow rapidly) that coordinate any provisioning mechanisms. Furthermore, survivability, in the presence of new failure scenarios that goes beyond the single failure assumption, is still of the utmost importance to minimize the network disruptions and data losses. In other words, protection against any possible future failure scenario where multiple faults may struck simultaneously, asks for highly reliable provisioning solutions.The above consideration have a general validity i.e., can be equally applied to any network segment and not just limited to the core part. So, we also address the problem of service provisioning in the access paradigm. Long reach Passive Optical Networks (PONs) are gaining popularity due to their cost, reach, and bandwidth advantages in the access region. In PON, the design of an efficient bandwidth sharing mechanism between multiple subscribers in the upstream direction is crucial. In addition, Long Reach PONs (LR-PONs) introduces additional challenges in terms of packet delay and network throughput, due to their extended reach. It becomes apparent that effective solutions to the connection provisioning problem in both the core and access optical networks with respect to the considerations made above can ensure a truly optimal end-to-end connectivity while making an efficient usage of resources.The first part of this thesis focuses on a control and management framework specifically designed for concurrent resource optimization in WDM-based optical networks in a highly dynamic traffic scenario. The framework and the proposed provisioning strategies are specifically designed with the objective of: (i) allowing for a reduction of the blocking probability and the control overhead in a Path Computation Element (PCE)-based network architecture, (ii) optimizing resource utilization for a traffic scenario that require services with diverse survivability requirements which are achieved by means of dedicated and shared path-protection, and (iii) designing provisioning mechanism that guarantees high connection availability levels in Double Link Failures (DLF) scenarios. The presented results show that the proposed dynamic provisioning approach can significantly improve the network blocking performance while making an efficient use of primary/backup resources whenever protection is required by the provisioned services. Furthermore, the proposed DLF schemes show good performance in terms of minimizing disruption periods, and allowing for enhanced network robustness when specific services require high connection availability levels.In the second part of this thesis, we propose efficient resource provisioning strategies for LR-PON. The objective is to optimize the bandwidth allocation in LR-PONs, in particular to: (i) identify the performance limitations associated with traditional (short reach) TDM-PON based Dynamic Bandwidth Allocation (DBA) algorithms when employed in long reach scenarios, and (ii) devise efficient DBA algorithms that can mitigate the performance limitations imposed by an extended reach. Our proposed schemes show noticeable performance gains when compared with conventional DBA algorithms for short-reach PON as well as specifically devised approaches for long reach.
|
|
