Optical transport network layered architecture for the MOONET

… , 2009. ICTON'09. …, 2009

PlaNet is a multilayer network planning tool designed and developed at the University of Texas at Dallas. This paper illustrates some of the features of PlaNet-OTN, one of the modules available in the PlaNet tool. PlaNet-OTN can be used to design and plan an optical transport network (OTN), which is comprised of two layers: wavelength division multiplexing (WDM) layer, which deals with wavelength allocation and routing of WDM services, and optical transport network (OTN) layer, which deals with optical data unit (ODU) equipment provisioning and routing of ODU services. Features of the PlaNet-OTN module include: multiple protection schemes and routing constraints for both WDM and ODU services, network equipment cost minimization, load balancing of traffic, and user-controlled run time of the optimization process. As shown in this paper, the PlaNet-OTN module is capable of computing service routes, allocating and configuring network equipment at both WDM and OTN layers and optimizing equipment usage, hence reducing the cost of the whole network.

2005

ATM asynchronous transfer mode BER bit error rate bps bits per second BT British Telecommunications CAD computer aided design CWDM coarse wavelength division multiplexing DARPA Defense Advanced Research Project Agency (United States) dB decibel DCS digital cross-connect system DS digital system (PDH signal) DWDM dense wavelength division multiplexing EDFA erbium-doped fiber amplifier EON European Optical Network FDM frequency division multiplexing FTIR Fourier transform infrared Gbps gigabits per second GHz gigahertz GUI graphical user interface IP Internet protocol ISP Internet service provider ITU International Telecommunications Union LAN local area network LED light emitting diode MAN metropolitan area network MB megabyte Mbps megabits per second MEMS micro electro-mechanical systems MONET multi-wavelength optical networking MPLS multi-protocol label switching vi 7 Conclusion References Bibliography xi Chapter 1 Introduction Optical fiber technology has a broad base of applications, including industrial, medical and communications. This investigation focuses exclusively on the application of optical fiber technology in the communications domain. Within the communications domain the use of optical fiber technology is not new, with operational commercial installations dating back to the early 1970's. These installations and the overwhelming majority of installations done today can be loosely classified as optical fiber equipped communication networks, since they are actually conventional communication networks that merely harness the cost and performance benefits of optical fiber links. The routing and consequent intelligence of these optical fiber networks still depend on electronic components with opto-electronic input interfaces and electro-optic output interfaces. True optical networking is however very young, with the testing of experimental nextgeneration optical networks only commencing in the early 2000's. True optical networks are communication networks that not only utilise optical fiber on its links for the cost and performance benefits that it offers above conventional copper cables, but also for the new multiplexing and routing dimension that wavelength University of Pretoria Electrical, Electronic and Computer Engineering establish an appreciation for the fact that routing and channel assignment is only one component of the network design problem, and not the only as is often suggested.

2015

Proceedings of the IEEE, 1993

Remarkable technological progress has been made in the development of Optical Transport Networks during the past decade. An optical transport network is a digital signal transport plarform which provides jexible and powerful signal transmission capabilities needed to create telecommunication services networks. This paper highlights the key technologies required for the development of optical transport networks; optical jiber transmission, and digital transport which includes transmission signal multiplexing, transport nodes, and network operation functions. The trends in transport technology evolution, the impact of SDH and ATM, the role of TMN (Telecommunications Management Networks), and network integrity enhancement techniques are elucidated. It is demonstrated that these technologies have brought about a dramatic change in transport network design and performance. Further innovations are required to fully realize a high-performance computer communication network, a cost-effective nationwide BISDN, and local networks for video distribution. These include the realization of an optical access transport network, and the extension of trunk network capabilities which will be possible with optical path layer technologies.

2020

A typical optical transport network interconnects multitudes of offices. With the advent of the Internet of Things (IoT) networking approach, it has become necessary for such transport structures to be flexible enough to accommodate heterogeneous communication services that generate escalating traffic loads every time. It is also key not only to accommodating continuously escalating traffic levels, but also to maintain a consistent Quality of Service, operability as well availability. This can only be achieved through the provisioning of effective and dynamic network control. In this paper, we explore the various operational issues such as incompatibilities in terms of physical layer transmission requirements and other control and management challenges emerging in present and future/ (envisaged) optical transport networks.

Proceedings of 2003 5th International Conference on Transparent Optical Networks, 2003., 2003

The growth of bandwidth demand for data traffic drives the evolution of the current transport networks towards the introduction of the Automatic Switched Optical Network (ASON). Introducing automatic switching capabilities in optical networks means designing and implementing control functionalities. Such as functionalities are hosted at the network Control Plane, and mainly consist of providing signalling and routing mechanisms distributed throughout the network. This paper addresses some issues still under discussion on the definition of a suitable control plane for optical core networks. Specifically, we deal with the routing protocol, which defines the distribution of topology information, the path selection and the association of nodes in a network; and with the routing mechanism, which allows selecting the path according to attributes of the connection requests and the available resources in the network. We also deal with the traffic engineering strategies used to optimise the use of these resources and give a quick view of future trends in Optical Networks. A Control Plane consists of the following aspects:

Computer Networks, 2006

Although the automatically switched optical networks (ASON) specifications strongly recommend a hierarchical network architecture for these networks, this is still an open issue. The hierarchical network concept involves several mechanisms mainly related with signaling and routing, such as the aggregation scheme, the dissemination process, the updating policy and the routing algorithms. The existing mechanisms for flat networks must be substantially modified to be applied to a hierarchical network architecture. In this paper, authors propose a complete hierarchical routing approach mainly focusing on routing concerns, aiming to optimize the global network performance while guaranteeing scalability.

IJCSNS, 2011

In optical networks, a connection is used to transmit data between source and destination nodes via lightpaths. The optical signal transmitted along a lightpath requires cross-connect switches (OXCs) and telecommunication carriers to switch high-speed optical signals in a fiber optic network. As a signal propagates from the source to the destination, the signal quality is continuously degraded by optical network components and impairments. Wavelength routing networks have two main problems: network design (fiber topology) and traffic requirements (traffic matrix). The network design problem is divided into lightpath topology design (LTD) and routing and wavelength assignment (RWA) problems. The RWA problem is more important for increasing the effectiveness of optical networks. The lightpath routing sub-problem requires determining the physical links for each lightpath that consist of optical channels. The wavelength assignment (WA) sub-problem requires determining the wavelength that each lightpath uses, i.e., assigning a wavelength to each lightpath in the logical topology such that wavelength restrictions are obeyed for each physical link. In this article, we discuss the important concepts of optical networks and the factors that affect in RWAs directly or indirectly.

Journal of Lightwave Technology, 2018

Automating the provisioning of telecommunications services, deployed over a heterogeneous infrastructure (in terms of domains, technologies and management platforms), remains a complex task, yet driven by the constant need to reduce costs and service deployment time. This is more so, when such services are increasingly conceived around interconnected functions and require allocation of computing, storage and networking resources. This automation drives the development of service and resource orchestration platforms that extend, integrate and build on top of existing approaches, macroscopically adopting Software Defined Networking principles, leveraging programmability and open control in view of inter-operability. Such systems are combining centralized and distributed elements, integrating platforms whose development may happen independently and parallel, and are constantly adapting to ever changing requirements, such as virtualization and slicing. Of specific interest is the (optical) transport network segment, traditionally operated independently via closed proprietary systems, and characterized by being relatively complex and hard to reach consensus regarding modelling and abstraction. In view of the targets, the transport network segment needs to be integrated into such service orchestration platforms efficiently. In this context, this paper aims at providing an introduction to control, management and orchestration systems, of which the network control is a core component, along their main drivers, key benefits and functional/protocol architectures. It covers multi-domain and multi-layer networks and includes complex use cases, challenges and current trends such as joint cloud/network orchestration and 5G network slicing.

IEEE Communications Magazine, 2000

Previous techniques for the management and control of optical transport networks are proving inadequate in today's rapidly evolving multivendor environments. This article examines the issues and challenges involved in developing a standardized optical network control plane. The control of optical transport networks is decomposed into provisioning models, a circuit provisioning process based on signaling, a neighbor and service discovery process, and a topology and resource discovery process. Unique properties and challenges of optical transport networks are explained in the context of these functions.