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QoS Mechanisms (qo + mechanism)

Distribution by Scientific Domains

Information Science and Computing	75%

Selected Abstracts

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]

Performance of delay-sensitive traffic in multi-layered satellite IP networks with on-board processing capability

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 12 2007
Suzan Bayhan
Abstract In this article, performance of delay-sensitive traffic in multi-layered satellite Internet Protocol (IP) networks with on-board processing (OBP) capability is investigated. With OBP, a satellite can process the received data, and according to the nature of application, it can decide on the transmission properties. First, we present a concise overview of relevant aspects of satellite networks to delay-sensitive traffic and routing. Then, in order to improve the system performance for delay-sensitive traffic, specifically Voice over Internet Protocol (VoIP), a novel adaptive routing mechanism in two-layered satellite network considering the network's real-time information is introduced and evaluated. Adaptive Routing Protocol for Quality of Service (ARPQ) utilizes OBP and avoids congestion by distributing traffic load between medium-Earth orbit and low-Earth orbit layers. We utilize a prioritized queueing policy to satisfy quality-of-service (QoS) requirements of delay-sensitive applications while evading non-real-time traffic suffer low performance level. The simulation results verify that multi-layered satellite networks with OBP capabilities and QoS mechanisms are essential for feasibility of packet-based high-quality delay-sensitive services which are expected to be the vital components of next-generation communications networks. Copyright © 2007 John Wiley & Sons, Ltd. [source]

QoS experiences in native IPv6 networks

INTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 2 2009
Athanassios Liakopoulos
Deployment of IPv6 technology in research and commercial networks has accelerated in the last few years. Inevitably, as more advanced services take advantage of the new technology, IPv6 traffic gradually increases. Today, there is limited experience in the deployment of Quality of Service (QoS) for IPv6 traffic in backbone networks that support the Differentiated Services framework. As available software and hardware are designed to handle IPv4 packets, there is a need to accurately measure and validate performance of QoS mechanisms in an IPv6 environment. This paper discusses tests and technical challenges in the deployment of IPv6 QoS in core networks, namely the production dual stack gigabit-speed Greek Research and Education Network (GRNET) and the IPv6-only 6NET European test network, using both hardware and software platforms. In either case, we succeeded in delivering advanced transport services to IPv6 traffic and provided different performance guarantees to portions of traffic. The deployed QoS schema was common to IPv6 and IPv4; in most cases both v4 and v6 traffic exhibited comparable performance per class, while imposing no significantly different overhead on network elements. A major conclusion of our tests is that the IPv6 QoS mechanisms are efficiently supported with state-of-the-art router cards at gigabit speeds. Copyright © 2008 John Wiley & Sons, Ltd. [source]