Optical Access Networks

2021 ◽  
pp. 161-188
Author(s):  
Debasish Datta
Keyword(s):  
Optical Networks ◽  
Communication Networks ◽  
Bandwidth Allocation ◽  
Data Access ◽  
Building Blocks ◽  
Access Networks ◽  
Coverage Area ◽  
Optical Access ◽  
Last Mile ◽  
Video Services

Access networks have evolved relentlessly over time in diverse directions. For example, PSTN initially provided only landline voice services in the last mile and later offered data-access using dial-up, ISDN, and ADSL technologies. Similarly, cable TV and mobile communication networks introduced data and voice/video services, while LANs and Wi-Fi networks evolved offering voice and video services. Following these developments, the demands for larger bandwidth and coverage area in the access segment increased and led to optical-access networking solutions using passive optical networks (PONs). With two wavelengths for the upstream/downstream transmissions over tree topology, PONs use TDM for the downstream transmission to the users and TDMA in the upstream with the dynamic bandwidth allocation (DBA) scheme. This chapter focuses on PONs, presenting the building blocks and MAC protocols using appropriate DBA schemes. Finally, the chapter presents various PON standards: EPON, GPON, 10G EPON, and XG-PON. (144 words)

Optimized Dynamic Bandwidth Allocation Algorithm for Optical Access Networks

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Ankur Singhal ◽  
Amit Gupta ◽  
Surbhi Bakshi
Keyword(s):  
Optical Networks ◽  
Bandwidth Allocation ◽  
Optical Network ◽  
Arrival Rate ◽  
Access Networks ◽  
Dynamic Bandwidth Allocation ◽  
Optical Access Networks ◽  
Average Delay ◽  
Optical Access ◽  
Dynamic Bandwidth

AbstractBandwidth assignment is a key issue in optical access networks, so an efficient mechanism is required for dynamic distribution of limited resources in the uplink channel among competing subscriber optical network units (ONUs). This paper presents a novel optimized dynamic bandwidth allocation (ODBA) algorithm for hybrid WDM/TDM passive optical networks. ODBA algorithm operates using information frame length of the subscriber’s ONUs and their information arrival rate; both of these factors finalize the assigned transmission capacity to the users. The system performance under differing offered traffic loads is evaluated in terms of network throughput, average delay and channel utilization. Further, the proposed ODBA scheme is validated by performing a comparative analysis with well-known algorithms.

scholarly journals Polarization-transparent silicon photonic add-drop multiplexer with wideband hitless tuneability

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Francesco Morichetti ◽  
Maziyar Milanizadeh ◽  
Matteo Petrini ◽  
Francesco Zanetto ◽  
Giorgio Ferrari ◽  
...  
Keyword(s):  
Optical Networks ◽  
Communication Networks ◽  
Bandwidth Allocation ◽  
Core Networks ◽  
Reconfigurable Devices ◽  
Silicon Photonic ◽  
Transmission Quality ◽  
And Control ◽  
Integrated Device ◽  
Dynamic Bandwidth

AbstractFlexible optical networks require reconfigurable devices with operation on a wavelength range of several tens of nanometers, hitless tuneability (i.e. transparency to other channels during reconfiguration), and polarization independence. All these requirements have not been achieved yet in a single photonic integrated device and this is the reason why the potential of integrated photonics is still largely unexploited in the nodes of optical communication networks. Here we report on a fully-reconfigurable add-drop silicon photonic filter, which can be tuned well beyond the extended C-band (almost 100 nm) in a complete hitless (>35 dB channel isolation) and polarization transparent (1.2 dB polarization dependent loss) way. This achievement is the result of blended strategies applied to the design, calibration, tuning and control of the device. Transmission quality assessment on dual polarization 100 Gbit/s (QPSK) and 200 Gbit/s (16-QAM) signals demonstrates the suitability for dynamic bandwidth allocation in core networks, backhaul networks, intra- and inter-datacenter interconnects.

WDM Access Networks

2021 ◽  
pp. 299-320
Author(s):  
Debasish Datta
Keyword(s):  
Optical Fibers ◽  
Mobile Networks ◽  
Bandwidth Allocation ◽  
Service Providers ◽  
Network Capacity ◽  
Access Networks ◽  
Optical Networking ◽  
Coverage Area ◽  
Wdm Transmission ◽  
Capacity And Coverage

In TDM PONs, or simply PONs, the transmission capacity of optical fibers remains under-utilized with single-wavelength transmissions for both upstream and downstream traffic. Use of WDM transmission in PONs can significantly enhance the overall network capacity and coverage area. WDM transmission in PONs can be realized in several ways, such as by using WDM exclusively or combining WDM with TDM, leading to WDM PONs and TDM-WDM PONs (TWDM PONs). This chapter gives several candidate physical configurations to realize WDM and TWDM PONs, and describes some useful dynamic wavelength-bandwidth allocation (DWBA) schemes for the latter. We also briefly discuss the needs of open access to the PON-based access networks for the various stakeholders, such as service providers and network providers. Finally, we describe briefly the roles of optical networking in the access segment of mobile networks. (135 words)

Electrical Spreading Code-Based OFDM Optical Access Networks for Budget Enhancement and Reduced System Bandwidth Requirement

2015 ◽  
Vol 36 (4) ◽  
Author(s):  
Pravindra Kumar ◽  
Anand Srivastava
Keyword(s):  
Optical Networks ◽  
Orthogonal Frequency Division Multiplexing ◽  
High Speed ◽  
Optical Network ◽  
Access Networks ◽  
Passive Optical Network ◽  
Spreading Code ◽  
Optical Access Networks ◽  
Optical Access ◽  
Code Division Multiple

AbstractPassive optical networks based on orthogonal frequency division multiplexing (OFDM-PON) give better performance in high-speed optical access networks. For further improvement in performance, a new architecture of OFDM-PON based on spreading code in electrical domain is proposed and analytically analyzed in this paper. This approach is referred as hybrid multi-carrier code division multiple access-passive optical network (MC-CDMA-PON). Analytical results show that at bit error rate (BER) of 10

scholarly journals An Energy-Efficient Distributed Dynamic Bandwidth Allocation Algorithm for Passive Optical Access Networks

2020 ◽  
Vol 12 (6) ◽  
pp. 2264 ◽  
Author(s):  
Hamzeh Khalili ◽  
David Rincón ◽  
Sebastià Sallent ◽  
José Ramón Piney
Keyword(s):  
Energy Consumption ◽  
Energy Efficient ◽  
Bandwidth Allocation ◽  
Access Networks ◽  
Dynamic Bandwidth Allocation ◽  
Sleep Mode ◽  
Optical Access Networks ◽  
Optical Access ◽  
Wide Range ◽  
Dynamic Bandwidth

The rapid deployment of passive optical access networks (PONs) increases the global energy consumption of networking infrastructure. This paper focuses on the minimization of energy consumption in Ethernet PONs (EPONs). We present an energy-efficient, distributed dynamic bandwidth allocation (DBA) algorithm able to power off the transmitter and receiver of an optical network unit (ONU) when there is no upstream or downstream traffic. Our main contribution is combining the advantages of a distributed DBA (namely, a smaller packet delay compared to centralized DBAs, due to less time being needed to allocate the transmission slot) with energy saving features (that come at a price of longer delays due to the longer queue waiting times when transmitters are switched off). The proposed algorithm analyzes the queue size of the ONUs in order to switch them to doze/sleep mode when there is no upstream/downstream traffic in the network, respectively. Our results show that we minimized the ONU energy consumption across a wide range of network loads while keeping delay bounded.

Design and implementation of flexible TWDM-PON with PtP WDM overlay based on WSS for next-generation optical access networks

2016 ◽  
Vol 30 (25) ◽  
pp. 1650324
Author(s):  
Bin Wu ◽  
Hongxi Yin ◽  
Jie Qin ◽  
Chang Liu ◽  
Anliang Liu ◽  
...  
Keyword(s):  
Wavelength Division Multiplexing ◽  
Bandwidth Allocation ◽  
Access Networks ◽  
Passive Optical Network ◽  
Optical Access Networks ◽  
Next Generation ◽  
Optical Access ◽  
Wavelength Division ◽  
Point To Point ◽  
Wdm Pon

Aiming at the increasing demand of the diversification services and flexible bandwidth allocation of the future access networks, a flexible passive optical network (PON) scheme combining time and wavelength division multiplexing (TWDM) with point-to-point wavelength division multiplexing (PtP WDM) overlay is proposed for the next-generation optical access networks in this paper. A novel software-defined optical distribution network (ODN) structure is designed based on wavelength selective switches (WSS), which can implement wavelength and bandwidth dynamical allocations and suits for the bursty traffic. The experimental results reveal that the TWDM-PON can provide 40 Gb/s downstream and 10 Gb/s upstream data transmission, while the PtP WDM-PON can support 10 GHz point-to-point dedicated bandwidth as the overlay complement system. The wavelengths of the TWDM-PON and PtP WDM-PON are allocated dynamically based on WSS, which verifies the feasibility of the proposed structure.

scholarly journals A QoS-Aware Dynamic Bandwidth Allocation Algorithm for Passive Optical Networks with Non-Zero Laser Tuning Time

Photonics ◽  
2021 ◽  
Vol 8 (5) ◽  
pp. 159
Author(s):  
Mohammad Zehri ◽  
Adebanjo Haastrup ◽  
David Rincón ◽  
José Ramón Piney ◽  
Sebastià Sallent ◽  
...  
Keyword(s):  
Optical Networks ◽  
Wavelength Division Multiplexing ◽  
Bandwidth Allocation ◽  
Access Networks ◽  
The Other ◽  
Dynamic Bandwidth Allocation ◽  
Tuning Time ◽  
Qos Differentiation ◽  
Dynamic Bandwidth ◽  
Laser Tuning

The deployment of new 5G services and future demands for 6G make it necessary to increase the performance of access networks. This challenge has prompted the development of new standardization proposals for Passive Optical access Networks (PONs) that offer greater bandwidth, greater reach and a higher rate of aggregation of users per fiber, being Time- and Wavelength-Division Multiplexing (TWDM) a promising technological solution for increasing the capacity by up to 40 Gbps by using several wavelengths. This solution introduces tunable transceivers into the Optical Network Units (ONUs) for switching from one wavelength to the other, thus addressing the ever-increasing bandwidth demands in residential broadband and mobile fronthaul networks based on Fiber to the Home (FTTH) technology. This adds complexity and sources of inefficiency, such as the laser tuning time (LTT) delay, which is often ignored when evaluating the performance of Dynamic Bandwidth Allocation (DBA) mechanisms. We present a novel DBA algorithm that dynamically handles the allocation of bandwidth and switches the ONUs’ lasers from one wavelength to the other while taking LTT into consideration. To optimize the packet delay, we introduce a scheduling mechanism that follows the Longest Processing Time first (LPT) scheduling discipline, which is implemented over the Interleaved Polling with Adaptive Cycle Time (IPACT) DBA. We also provide quality of service (QoS) differentiation by introducing the Max-Min Weighted Fair Share Queuing principle (WFQ) into the algorithm. The performance of our algorithm is evaluated through simulations against the original IPACT algorithm, which we have extended to support multi-wavelengths. With the introduction of LPT, we obtain an improved performance of up to 73% reduction in queue delay over IPACT while achieving QoS differentiation with WFQ.

Bandwidth Allocation Methods in Passive Optical Access Networks (PONs)

2010 ◽  
pp. 123-145
Author(s):  
Noemí Merayo ◽  
Patricia Fernández ◽  
Ramón J. Durán ◽  
Rubén M. Lorenzo ◽  
Ignacio de Miguel ◽  
...  
Keyword(s):  
Optical Networks ◽  
Bandwidth Allocation ◽  
Medium Access Control Protocol ◽  
Access Networks ◽  
Dynamic Bandwidth Allocation ◽  
Medium Access ◽  
Traffic Conditions ◽  
Time Division ◽  
Dynamic Bandwidth

Passive Optical Networks (PONs) are very suitable architectures to face today’s access challenges. This technology shows a very cost saving architecture, it provides a huge amount of bandwidth and efficiently supports Quality of Service (QoS). In PON networks, as all subscribers share the same uplink channel, a medium access control protocol is required to provide a contention method to access the channel. As the performance of Time Division Multiplexing Access (TDMA) protocol is not good enough because traffic nature is heterogeneous, Dynamic Bandwidth Allocation (DBA) algorithms are proposed to overcome the problem. These algorithms are very efficient as they adapt the bandwidth assignment depending on the updated requirements and traffic conditions. Moreover, they should offer QoS by means of both class of service and subscriber differentiation. Long-Reach PONs, which combine the access and the metro network into only one by using 100 km of fibre, is an emergent technology able to reach a large number of far subscribers and to decrease the associated costs.

Sign in / Sign up

Export Citation Format

Share Document