The dynamicbandwidthallocation (DBA) algorithm is required for efficient bandwidth utilization in XG-PON. The majority of existing DBA algorithms do not make use of the unused bandwidth of a queue with other service...
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The dynamicbandwidthallocation (DBA) algorithm is required for efficient bandwidth utilization in XG-PON. The majority of existing DBA algorithms do not make use of the unused bandwidth of a queue with other service classes queue. In the update operation, the efficient bandwidth utilization (EBU) method employs a Borrow Refund (BR) method to utilize unused bandwidth between traffic class queues. This paper presents an extra efficient bandwidth utilization (EEBU) algorithm, which overcomes the limitations mentioned above with proper polling and scheduling mechanism. The theoretical and simulation results show that EEBU improvements for T-CONT 2 delay are 1% and 10%, and for T-CONT 3 delay are 8% and 22%, and for T-CONT 4 delay by 6% and 4.5% compared to the EBU and Giga PON access network (GIANT) respectively.
We previously proposed an energy-efficient Just-In-Time based dynamic bandwidth allocation algorithm for the 10 Gbps Ethernet Passive Optical Network. The algorithm exploits the capability of the Vertical-Cavity Surfa...
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ISBN:
(纸本)9781467325165
We previously proposed an energy-efficient Just-In-Time based dynamic bandwidth allocation algorithm for the 10 Gbps Ethernet Passive Optical Network. The algorithm exploits the capability of the Vertical-Cavity Surface-Emitting Optical Laser based Optical Network Units to operate in sleep or doze mode during its idle time. The algorithm takes into account the upstream traffic demand at the Optical Network Units in determining the bandwidth allocated to each Optical Network Unit during each cycle, thus eliminating possible collisions in the network. In this work we evaluate the performance of the Vertical-Cavity Surface-Emitting Laser and the Distributed Feedback Laser based Optical Network Units under the proposed algorithm. The simulation results indicate that the Vertical-Cavity Surface-Emitting Laser based Optical Network Unit outperforms the DFB ONU in terms of the energy efficiency using the proposed algorithm.
In this paper, an (overlap and non-overlap)-based dynamicbandwidthallocation (DBA) algorithm with wavelength optimal length (WOL) for upstream channel in multi-OLT passive optical network (PON) is proposed. By intro...
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In this paper, an (overlap and non-overlap)-based dynamicbandwidthallocation (DBA) algorithm with wavelength optimal length (WOL) for upstream channel in multi-OLT passive optical network (PON) is proposed. By introducing optical line terminal (OLT) pool, the problem of OLT services imbalance is solved. Based on the service and its weight factor, proportion algorithm is constructed to allocate OLTs and wavelengths to OLT pool and wavelength group respectively. By proposing a new concept of WOL, the bandwidth wastage is reduced. By presenting overlap and non-overlap algorithms, the bandwidth utilization is improved further. By the simulation and analysis, the effectiveness of the proposed algorithms is demonstrated.
A passive optical network (PON) with multiple optical line terminals (OLTs) will play an important role in the optical access network. In this study, a novel dynamicbandwidthallocation (DBA) algorithm for the downst...
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A passive optical network (PON) with multiple optical line terminals (OLTs) will play an important role in the optical access network. In this study, a novel dynamicbandwidthallocation (DBA) algorithm for the downstream channel in a multi-OLT PON is proposed. To take care of bandwidth demands of different users, weight factors are introduced. Based on different weight factors, a core framework of the algorithm is constructed. Moreover, by combining a decision criterion and a bandwidth surplus ratio, a mathematical model of release bandwidth is established. Furthermore, by uniting judgement conditions and overload amount, a mathematical model of allocationbandwidth is also built. By constructing two mathematical models, the order and amount of release and allocationbandwidth are effectively solved. Moreover, to describe accurately the power of bandwidth transfer, a new concept bandwidth-transfer work' is introduced. Based on the bandwidth-transfer work, a ranking model is created to maximise the efficiency of the DBA. Finally, the effectiveness of the DBA algorithm and ranking model is demonstrated by the simulation and analysis.
The conventional open access optical network (OAN) with point to multipoint structure needs active components to cover large number of users in a wide area. Requirement of more active components significantly increase...
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The conventional open access optical network (OAN) with point to multipoint structure needs active components to cover large number of users in a wide area. Requirement of more active components significantly increase the network deployment costs. Cover large range congregation of point to multipoint networks is one of the effective solutions to reduce the network deployment costs. This idea offers the long-reach passive optical network (LR-PON) concept with 100 Km spanning the conventional OAN without any active components between sources to destination. However, the LR-PON involves larger propagation delay as well as end-to-end packet delay compared to the conventional PON system, i. e., spanning distance of 20 km. These delays significantly degrade the performances of the LR-PON with the existing centralized dynamicbandwidthallocation (DBA) algorithms. That is why advanced DBA schemes compatible to the LR-PON are required to reduce its longer propagation as well as end-to-end delays. Proper scheduling of the Report and Gate messages is one of the main challenges to design a new DBA algorithm for the LR-PON. Without proper scheduling of the Report and Gate messages, the LR-PON system suffers from over-granting problem. In this thesis, we propose two DBA schemes, i. e., scheme1 and scheme2, for the LR- PON system. The scheme1 is used to reduce the end-to-end packet delay while the scheme2 is used to mitigate the over-granting problem. In the scheme1, the maximum length of a time cycle is subdivided into multiple units called grant processing units and rapidly grants the window size to each optical network unit (ONU). In the scheme2, in the Report message, each ONU sends the frame information instead of total buffer occupancy to avoid the over-granting problem. The combined effect of the scheme1 and scheme2 effectively improves the overall quality of services (QoSs) of the LR-PON system. The performances of the proposed schemes have been evaluated by numerical sim
In this paper, we propose a new dynamicbandwidthallocation (DBA) algorithm for multimedia services over Ethernet PONs (passive optical networks). The proposed algorithm is composed of a low-level scheduler in the op...
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In this paper, we propose a new dynamicbandwidthallocation (DBA) algorithm for multimedia services over Ethernet PONs (passive optical networks). The proposed algorithm is composed of a low-level scheduler in the optical network unit (ONU) and a high-level scheduler in the optical tine terminal (OLT). The hierarchical DBA algorithm can provide expansibility and efficient resource allocation in an Ethernet PON system in which the packet scheduler is separated from the queues. In the proposed DBA algorithm, the OLT allocates bandwidth to the ONUs in proportion to the weight associated with their class and queue length, while the ONU preferentially allocates its bandwidth to queues with a static priority order. The proposed algorithm provides an efficient resource utilization by reducing the unused remaining bandwidth caused by the variable length of the packets. We also define the service classes and present control message formats conforming to the multi-point control protocol (MPCP) over an Ethernet PON. In order to evaluate the performance, we designed an Ethernet PON system on the basis of IEEE 802.3ah "Ethernet in the first mile" (EFM) using OPNET and carried out simulations. The results are analyzed in terms of the channel utilization, queuing delay, and ratio of the unused remaining bandwidth.
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