Optical Transport Network

About: Optical Transport Network is a research topic. Over the lifetime, 6055 publications have been published within this topic receiving 85783 citations.

Wavelength division multiplexed multi-frequency optical source and broadband incoherent optical source

Abstract: A wavelength division multiplexing multi-frequency optical source is used to provide downstream transmission of information signals at discrete optical wavelengths from a central office to a plurality of optical network units. A passive optical demultiplexer in a remote node routes the downstream information signals to the optical networks according to optical wavelength. Broadband incoherent sources are used to provide upstream information signals at discrete optical wavelengths which are multiplexed and then routed to the central office for demultiplexing by the passive optical demultiplexer. A wavelength selective coupler in the central office and in each optical network unit combines and segregates downstream and upstream signals of different optical wavelengths for routing to a desired destination.

Fault detection for all-optical add-drop multiplexer

Abstract: A fault detecting apparatus and method for a network node of an optical transmission system receives a wavelength division multiplexed (WDM) optical signal which includes a group of optical channels. The network node includes an optical demultiplexer, optical switch, optical multiplexer, and an optical channel add/drop device. Supervisory optical signals having a different wavelength than the wavelengths of the group of optical channels are generated and spliced with each optical channel by the optical demultiplexer. The supervisory channel optical power is tapped off at various points in the network node, such as the output optical channels of the demultiplexer, dropped optical channel outputs, output optical channels from the optical switch, and the output WDM optical signal of the multiplexer. The supervisory channels are monitored by a wavemeter for bypass lightpaths and dropped lightpaths. Added optical channels are monitored by monitoring a portion of the signal power in the added lightpath of the added optical channel. If the wavemeter detects the absence of the supervisory signal, or the portion of the added optical channel, this indicates a fault condition and the network control is notified to effect correction of the fault.

Optical Communications Essentials

Abstract: Chapter 1: Basic Concepts of Communications SystemsChapter 2: Optical Communication Systems OverviewChapter 3: The Behavior of LightChapter 4: Optical FibersChapter 5: Optical Fiber CablesChapter 6: Light Sources and TransmittersChapter 7: Photoiodes and ReceiversChapter 8: Connectors and SplicesChapter 9: Passive Optical ComponentsChapter 10: Active Optical ComponentsChapter 11: Optical AmplifiersChapter 12: Wavelength Division MultiplexingChapter 13: Constructing the WDM Network PuzzleChapter 14: Performance MeasuresChapter 15: Performance ImpairmentsChapter 16: Optical Link DesignChapter 17: Optical NetworksChapter 18: Network ManagementChapter 19: Test and MeasurementChapter 20: Manufacturing IssuesAPPENDIX A: UNITS, PHYSICAL CONSTANTS, AND CONVERSION FACTORSAPPENDIX B: ITU-T FREQUENCY AND WAVELENGTH GRIDAPPENDIX C: ACRONYMSINDEX

Technologies and protocols for data center and cloud networking

Abstract: Data center and cloud architectures continue to evolve to address the needs of large-scale multi-tenant data centers and clouds. These needs are centered around seven dimensions: scalability in computing, storage, and bandwidth, scalability in network services, efficiency in resource utilization, agility in service creation, cost efficiency, service reliability, and security. This article focuses on the first five dimensions as they pertain to networking. Large data centers are targeting support for tens of thousands of servers, exabytes of storage, terabits per second of traffic, and tens of thousands of tenants. In a data center, server and storage resources are interconnected with packet switches and routers that provide for the bandwidth and multi-tenant virtual networking needs. Data centers are interconnected across the wide area network via routing and transport technologies to provide a pool of resources, known as the cloud. High-speed optical interfaces and dense wavelength-division multiplexing optical transport are used to provide for high-capacity transport intra- and inter-datacenter. This article reviews various switching, routing, and optical transport technologies, and their applicability in addressing the networking needs of large-scale multi-tenant data centers.

Design of a survivable WDM photonic network

Abstract: We consider schemes for protecting a network using a wavelength division multiplexing (WDM) infrastructure against component or link failures. First, we explain how protection can be achieved by hardware redundancy. Then, we consider that with WDM networks, the failure of a single link or component may cause the simultaneous failure of several optical channels, potentially making impossible the restoration by rerouting in higher layers (SDH, ATM, IP). To address this, we introduce the concept of design protection, which aims at making such failure propagation impossible. We present the disjoint alternate path (DAP) algorithm which places optical channels in order to maximise design protection. We show the result on the example of the ARPA-2 network.