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Optical Transport Networks (optical + transport_network)

Distribution by Scientific Domains

Engineering	75%

Selected Abstracts

Traffic analysis in optical burst switching networks: a trace-based case study

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 7 2009
Ahmad Rostami
Optical burst switching (OBS) appears as a promising technology for building dynamic optical transport networks. The main advantage of OBS is that it allows for dynamic allocation of resources at sub-wavelength granularity. Nevertheless, the burst contention problem, which occurs frequently inside the network, has to be addressed before OBS can be really deployed as the next generation optical transport network. Recently a lot of attention is devoted to different approaches for resolving contentions in OBS networks. Although performance analysis of these approaches is strongly dependent on the traffic characteristics in the network, the majority of the studies is so far based on very hypothetical traffic assumptions. In this study we use traces of real measurements in the Internet to derive realistic data about the traffic that is injected into the OBS network. Specifically, we investigate the marginal distributions of burst size, burst interdeparture time, assembly delay and number of packets per burst as well as the burstiness of the burst traces. We demonstrate that the performance of an OBS core node using the real traces is pretty similar to the results obtained when the traffic arriving to the core node is assumed to be Poisson. In fact, usage of the Poisson as the process of burst arrival to the core node leads in all the investigated cases to an upper bound on the burst drop rate at that node. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Radio resource management across multiple protocol layers in satellite networks: a tutorial overview

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 5 2005
Paolo Barsocchi
Abstract Satellite transmissions have an important role in telephone communications, television broadcasting, computer communications, maritime navigation, and military command and control. Moreover, in many situations they may be the only possible communication set-up. Trends in telecommunications indicate that four major growth market/service areas are messaging and navigation services (wireless and satellite), mobility services (wireless and satellite), video delivery services (cable and satellite), and interactive multimedia services (fibre/cable, satellite). When using geostationary satellites (GEO), the long propagation delay may have great impact, given the end-to-end delay user's requirements of relevant applications; moreover, atmospheric conditions may seriously affect data transmission. Since satellite bandwidth is a relatively scarce resource compared to the terrestrial one (e.g. in optical transport networks), and the environment is harsher, resource management of the radio segment plays an important role in the system's efficiency and economy. The radio resource management (RMM) entity is responsible for the utilization of the air interface resources, and covers power control, handover, admission control, congestion control, bandwidth allocation, and packet scheduling. RRM functions are crucial for the best possible utilization of the capacity. RRM functions can be implemented in different ways, thus having an impact on the overall system efficiency. This tutorial aims to provide an overview of satellite transmission aspects at various OSI layers, with emphasis on the MAC layer; some cross-layer solutions for bandwidth allocation are also indicated. Far from being an exhaustive survey (mainly due to the extensive nature of the subject), it offers the readers an extensive bibliography, which could be used for further research on specific aspects. Copyright © 2005 John Wiley & Sons, Ltd. [source]

On QoS mechanism profiling in MPLS-TP transport networks

BELL LABS TECHNICAL JOURNAL, Issue 4 2010
Christian Addeo
In the context of packet management in optical transport networks, quality of service (QoS) is playing an important role to achieve the right levels of bandwidth, latency, and general treatment for the different services carried over the network. The scope of this paper is to describe quality of service functionalities in the context of a packet transport network. This paper refers to the definition and implementation of the quality of service model in a packet transport network node, describing how this information is carried over a packet transport network. The Alcatel-Lucent 1850 Transport Service Switch (TSS) platform serves as our reference point for a packet transport node. We also include a description of classification, policing, marking, and, in particular, hierarchical scheduling and shaping. © 2010 Alcatel-Lucent. [source]