10 research outputs found
Analysis of topology aggregation techniques for QoS routing
We study and compare topology aggregation techniques used in QoS routing. Topology Aggregation (TA) is defined as a set of techniques that abstract or summarize the state information about the network topology to be exchanged, processed, and maintained by network nodes for routing purposes. Due to scalability, aggregation techniques have been an integral part of some routing protocols. However, TA has not been studied extensively except in a rather limited context. With the continuing growth of the Internet, scalability issues of QoS routing have been gaining importance. Therefore, we survey the current TA techniques, provide methodology to classify, evaluate, and compare their complexities and efficiencies. ©2007 ACM.postprin
QUALITY OF SERVICE DELIVERY: ECONOMIC EFFECTS OF MULTI-HOMING AND CONTENT DELIVERY NETWORKS
The structure of the Internet serves as a big commoditizer of all traffic. Therefore all data, be it time critical or not is transported at the same speed. However, recent trends in the internet are changing this structure. The practices of multi-homing and using content delivery networks reduce the commodity nature of data being transported and put terminating Internet service providers in a position to price discriminate against specific providers or types of traffic. We firstly formalize multi-homing and content delivery networks, we then derive end user prices for paid content and lastly show consequences of the modeled situation. We thus show how the two technologies to bypass crowded peerings change the Internet business model. Traffic which is sensitive to transport quality, such as business critical or delay sensitive traffic, will be paying higher fees to terminating ISPs
Hierarchical QoS routing in next generation optical networks
In this paper, we study the problem of inter-domain routing with two additive QoS constraints in hierarchical optical networks. We develop an inter-domain routing protocol that (1) identifies the QoS supported by the paths, (2) selects an inter-domain path that satisfies the QoS requirement of a connection request, and (3) reserves the wavelength on each link along the path in such a way that the number of wavelength converters needed is minimized. Both formal analyses and extensive simulation experiments show that our inter-domain routing protocol outperforms the existing protocols. © 2006 IEEE.published_or_final_versio
Routing with QoS Information Aggregation in Hierarchical Networks
Abstract-In this paper, we consider the problem of routing with two additive constraints in the hierarchical networks, such as the Internet. In order for scalability, the supported QoS information in the hierarchical networks has to be aggregated. We propose a novel method for aggregating the QoS information. To the best of our knowledge, our approach is the first study to use the area-minimization optimization, the de facto optimization problem of the QoS information aggregation. We use a set of real numbers to approximate the supported QoS between different domains. The size of the set is predefined so that advertisement overhead and the space requirement will not grow exponentially as the network size grows. The simulation results show that the proposed method outperforms the existing methods
Autonomes Netzwerkmanagement für ein dynamisches Routing unter Berücksichtigung von Qualitätsanforderungen
This PhD thesis is focused on the question: how can an autonomously working
routing management be designed to allow the transmission of application
data while considering quality requirements. To answer this the focus is on
a dynamic routing, whose decisions depend on the current distribution of
available link capacities in the network. The presented new solution
contains three protocols which work in a completely autonomous way. They
are used to cluster the network and place automatically management
instances, to assign addresses in the network as well as to distribute
continuously routing data among the network nodes. Based on this, all
routing tables are kept up to date, so that they represent the current
paths as well as they also describe the available QoS specific capacity for
each known route. By the help of this data, the routing algorithm, which is
applied in this PhD thesis, allows the transmission of data from different
applications while considering their quality requirements. In this context,
each needed routing decision is influenced by the currently existing load
situation in the network.Despite the introduced complex signaling, the
overall system remains compatible to IPv4/v6. Therefore, it can be used for
the transmission of audiovisual data in today’s networks. In such a
scenario the scalability of the resulting overall system is supported by
the data aggregations which are used within the signaling of the routing
management.The practical part of the work is divided into two areas. The
first one describes the software “Homer Conferencing”. It is usable as
standalone solution for video conferences and test environment for
audiovisual streams. By its help, qualitative differences in transmissions
can be presented. Additionally, the software provides graphical dialogs for
quantitative measurements of the data streams and packet losses. The second
practical part contains the implementation of the routing management and
applies all protocols on packet level. This was used as base for the
accomplished quantitative evaluations. They show the caused signaling
overhead as well as the resulting benefit of the introduced routing
management for selected base topologies of IP networks.Im Fokus dieser Dissertation steht die Frage, wie ein autonom ablaufendes
Routingmanagement aussehen kann, um in Netzwerken die Übertragung von
Anwendungsdaten unter Berücksichtigung von Qualitätsanforderungen zu
ermöglichen. Dabei steht ein dynamisches Routing im Vordergrund, dessen
Entscheidungen von der momentanen Verteilung von verfügbaren
Linkkapazitäten im Netzwerk abhängen. Die vorgestellte neuwertige Lösung
enthält drei vollständig autonom ablaufende Protokolle. Sie dienen zur
Netzwerkunterteilung und automatischen Platzierung von Managementinstanzen,
zur Adresszuweisung im Netzwerk sowie zur kontinuierlichen Verteilung von
Routingdaten unter den Netzwerkknoten. Dadurch werden alle Routingtabellen
aktuell gehalten, sodass sie die momentanen Pfade sowie auch die für jede
bekannte Route verfügbaren QoS spezifischen Eigenschaften beschreiben. Mit
Hilfe dieser Daten ist der in dieser Dissertation eingesetzte
Routingalgorithmus in der Lage, die Übertragung von Daten von
unterschiedlichen Anwendungen unter Beachtung ihrer Qualitätsanforderungen
zu ermöglichen. Dabei beeinflusst die aktuell vorliegende Lastsituation im
Netzwerk jede notwendige Routingentscheidung.Trotz der eingeführten
komplexen Signalisierungen bleibt das Gesamtsystem kompatibel zu IPv4/v6
und kann somit für die Übertragung von audiovisuellen Daten in heutigen
Netzwerken eingesetzt werden. Dabei profitiert die Skalierbarkeit des
resultierenden Gesamtsystems von den innerhalb der Signalisierungen des
Routingmanagements verwendeten Datenaggregationen.Der praktische Teil
dieser Arbeit ist zweigeteilt. Der erste Teil beschreibt die Software
„Homer Conferencing“. Sie ist als eigenständige Lösung für Videokonferenzen
und Testumgebung für audiovisuelle Ströme einsetzbar. Mit ihrer Hilfe
können qualitative Unterschiede in Übertragungen audiovisuell vorgeführt
werden. Die Software bietet zusätzlich grafische Dialoge zur quantitativen
Bemessung der Datenströme und Paketverluste. Der zweite praktische Teil
beinhaltet die Implementierung des Routingmanagements und setzt die
Protokolle auf Paketebene vollständig um. Dies diente als Basis für die
durchgeführten quantitativen Evaluierungen. Sie stellen für ausgewählte
Basistopologien von IP-Netzwerken den verursachten Signalisierungsaufwand
sowie den resultierenden Nutzen beim Einsatz des vorgestellten
Routingmanagements dar