Future photonic transport networks based on WDM technologies

Compact and efficient sources of high power ultrafast optical pulses are needed to incorporate high speed optical information processing techniques into future photonic networks. In this paper, the robust timing stability associated with optical mode-locked pulse trains from semiconductor diode lasers is examined as an alternative to standard methods of providing synchronous timing signals in future photonic networks. Here, it is demonstrated how these sources may play a role in several photonic network scenarios, such as optical clock distribution, photonic network synchronization, and all optical clock recovery.

This paper explores the technologies that will enable a further leap forward in transport network evolution. First, requirements of the future transport network are elucidated. Existing network cost is evaluated and the viable means to reduce transport network cost are identified. It is demonstrated that optical path technologies such as WP (wavelength path) and VWP (virtual wavelength path) will play a key role in this. They enhance not only transmission capacity but also cross‐connect node throughput cost‐effectively by capitalizing on the wavelength routeing scheme. Optical path realization technologies focusing on optical path cross‐connect systems are examined. Requirements for the optical path cross‐connect system are then elucidated, and a new cross‐connect system architecture is evaluated. The architecture exploits PLC (planar lightwave circuit) and other commercially available technologies suitable for large‐scale production. The evaluations include cross‐connect node upgradability, modular growth capability, total node cost, optical loss and switching power consumption. It is proved that the architecture has significant advantages over existing switch architectures. The optical path technologies provided in this paper will pave the way for a new transport network paradigm, a ubiquitous, bandwidth‐abundant and affordable broadband ISDN.

In the future photonic network, network applications such as grid computing and wide-area distributed SANs (storage area networks) will be realized on a new network platform called the “optical grid.” In this paper, an optical grid is studied, which would provide a network platform to networked applications such as grid computings in the future photonic network. The optical code (OC) label, an identifier for data flow, is an enabler due to its ultrafast processing capability. First, the variable-capacity OC-labeled path and optical code division multiplexed (OCDM) path are studied, which allow one to simultaneously set up a number of connections on a single wavelength path. Next, optical path setup using OC-labeled control packet, which bears the signaling message, is presented and experimentally demonstrated. This enables one to ultimately reduce the overhead time of the optical path setup. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 88(12): 1–10, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20241

1.5μm Fluoride-Based Fiber Amplifiers for Wideband Multichannel Transport Networks

The 5th generation of mobile communication system (5G) is expected to change the communication landscape by 2020. 5G will provide a unified platform for connecting billions of devices and offering a wide range of networking services. The use-cases and the disruptive capabilities of 5G will bring forward a number of challenges for both the wireless radio and wired part of a 5G network. The wired transport network, typically consisting of access and core domains, has to adopt tailored networking solutions satisfying differentiated quality of service requirements as envisioned in 5G. While optical transport technology has been prevalent in core segments, it is also perceived as a key enabler for the 5G access networks due to its very high capacity and low transmission delay. However, existing optical transport technologies are hindered by inflexibility, poor resource utilization, and high costs, and cannot be stretched to 5G scale. On the other hand, optical technologies have been going through a paradigm shift towards an elastic optical network that is considered as the promising solution for future high-speed transport networks. This paper outlines key challenges for the design of a flexible, programmable, and dynamic 5G transport network, and discusses the enabling technologies and directions to address these challenges.

Flexible and dynamic photonic node architecture for next generation software defined photonic network is described. The pooling architecture of universal transceivers provides the better utilization of network element. Also, network monitoring functionalities such as optical path trace and in-band OSNR monitor in future photonic network are shown in this paper.

In recent broadband photonic network system, high speed optical data transmission is required. Electrooptic (EO) polymers are attractive because of their large nonlinearity, fast response time and ease of device fabrication. Therefore the EO polymers are expected for the application of ultra-high speed EO switch and/or wide bandwidth EO modulator, both of which will be used in future photonic network. In this report, recent progress of EO polymers and their application to waveguide type devices are described.

In recent years and within the framework of its project “Algiers the metropolis”, Algiers has classified its transport network among its first concerns in order to compete with the other Mediterranean metropolises. However, the complexity of its territory, which is of a particular geological and geomorphological nature, represents a constraint for the proper distribution and management of its transport network. The complexity of its territory and of its transport network, leads us towards the systemic approach for the search of an adequacy between these two complex urban realities in order to find an effective and efficient tool of management and urban planning. The development of a set of indicators of sustainable mobility, as a result of this work, allowed us to find through an epistemological study of the literature on the two complex concepts to select and develop a list of Input and Output Indicators that are related to both territory and transport. Indeed, this list of sustainable mobility indicators will allow, on the one hand, in urban planning, a better match of the transport network to the Algerian territory and, on the other hand, the study of the effectiveness and efficiency of the present and future transport network.

During the 1990s, a lot of promises were made concerning optical switching and the role it will play in future transport networks. A new optical layer based on Wavelength Division Multiplexing (WDM) and optical switching was envisioned. As the industry is going through a downturn, optical switching has not been deployed and the optical layer has not been realized in practice. In this paper, we look at the past and present of optical switching and try to explore its potential in future networks.

The traffic carried by core optical networks grows at a steady but remarkable pace of 30-40% year-over-year. Optical transmissions and networking advancements continue to satisfy the traffic requirements by delivering the content over the network infrastructure in a cost and energy efficient manner. Such core optical networks serve the information traffic demands in a dynamic way, in response to requirements for shifting of traffics demands, both temporally (day/night) and spatially (business district/residential). However as we are approaching fundamental spectral efficiency limits of singlemode fibers, the scientific community is pursuing recently the development of an innovative, all-optical network architecture introducing the spatial degree of freedom when designing/operating future transport networks. Spacedivision- multiplexing through the use of bundled single mode fibers, and/or multi-core fibers and/or few-mode fibers can offer up to 100-fold capacity increase in future optical networks. The EU INSPACE project is working on the development of a complete spatial-spectral flexible optical networking solution, offering the network ultra-high capacity, flexibility and energy efficiency required to meet the challenges of delivering exponentially growing traffic demands in the internet over the next twenty years. In this paper we will present the motivation and main research activities of the INSPACE consortium towards the realization of the overall project solution.

With optical technology evolution, it becomes possible to perform all optical traffic grooming (AOTG) with a very fine granularity. In the context of flexible optical networking, AOTG paves the way to new possibilities in future transport networks. Finding the best trade-off between electrical and optical aggregation in intrinsically multi-layer transport networks is a complex challenge for operators. This paper compares CAPEX results and resource fill-in performances of electrical and optical aggregation solutions, through a real multilayer transport network case study.

In this paper we propose a unified model for dynamic bandwidth adaptation in future transport networks. It acts as an umbrella for both next generation SONET/SDH (NG-SONET/SDH) and even more general, networks with a GMPLS control plane. We adapt bandwidth in discrete steps by exploiting features of virtual concatenation and bundled links, respectively. Applying our model, we demonstrate its advantage in providing improved service quality in comparison to a scheduled provisioning scheme. We evaluate the adaptation granularity to provide a required quality of service for typical IP network traffic behavior in the access network. Furthermore we quantify in depth the impact of increasing access bandwidth at the network edge on signaling load in a transport network.

The mobile data traffic increase and the future connection of billions of Internet of Things (IoT) devices require operators to reshape the existing transport network architecture. Today, more than 50 % of Base-stations (BTS) are backhauled via radio. Radio technology can continue to play this vital role in future transport networks if it is able to evolve to cope with the new capacity level and latency requirements supporting the new 5G services. In this paper, a possible answer to this demand is provided, proposing a radio solution working in D-Band (130-170 GHz) and enabling a reconfigurable meshed network that can support the backhaul needs of future 5G and beyond networks.

The flexible operation of CO2 injection wells presents significant challenges. To avoid premature degradation of wells or loss of integrity it is imperative to understand the feed flow patterns that future CO2 transportation and storage networks will face. We use a unit commitment economic dispatch (UCED) model to study CCS operating regimes in low carbon energy systems scenarios that are characterised by high shares of weather dependent renewable power generation. Using the case study of Great Britain, we determine the extent to which flexible operation of CCS plants is required, resulting in variable CO2 flows that need to be accommodated by future CO2 transportation and storage networks. We find that around 21% and 12% of the net flow rate changes over 6h-periods in the core scenario have greater amplitudes than 30% and 50% of nominal flow, respectively. When changes are averaged over two consecutive blocks of 6 h, representing the smoothing effect achievable via line-packing over a pipeline of reasonable length and diameter, around 9% of the net changes have greater amplitudes than 40% of nominal flow. Given the high and frequent fluctuations in feed flows across all considered scenarios, further research is urgently required on the capability of transportation and storage networks to accommodate variable CO2 flow rates.

Photonic networks are the base of a future broadband Internet that permits an easy access to the variety of multimedia services. Optical frequency- and time-division multiplexing techniques enable an optimum matching of the photonic network's capacity to the increasing communications demand thereby reacting to the requirements of new services in a flexible way. Flexibility and reliability with high profitability are the crucial characteristics of future photonic networks.