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1
FINAMORE, ALESSANDRO. "Analysis, characterization and classification of Internet traffic." Doctoral thesis, Politecnico di Torino, 2012. http://hdl.handle.net/11583/2497191.
Full textAbstract:
The Internet is a global interconnection of networks representing nowadays
one of the most important telecommunication technologies.
Born as an U.S. military project, it has evolved in a worldwide communication
system used by people every day. This success is based
on its ``freedom'' since no single organization or administration
entity governs or maintains it. This freedom also motivates the huge
heterogeneity of Internet services available today ranging from
working activities (e.g., VoIP, e-mail, etc.) to entertainment
(e.g., video games, streaming, peer-to-peer, etc.) and commerce (e.g., Amazon, eBay, etc.)
just to name a few.
The Internet is a fertile and in constant evolution system.
Every year new services and software platforms are launched affecting
not only the users' activities (e.g. social networks) but also the internal architecture of the networks
(e.g., Content Delivery Network vs peer-to-peer) or the devices used to access to the services
(e.g., PC vs smartphones and Internet tablets).
The richness of the Internet scenario is paid at the cost of its internal complexity.
Eric Schmidt, the CEO of Google, said:
\emph{``The Internet is the first
thing that humanity has built that humanity doesn't
understand, the largest experiment in anarchy that we have ever
had.''}\footnote{\url{http://www.brainyquote.com/quotes/authors/e/eric_schmidt.html}}.
At the origins, the Internet has been designed to operate on few standardized services.
None could have i) foreseen the success of this media and ii) designed
the network to cope with the plethora of nowadays services.
If on the one hand this diversity provides the Internet with a certain
level of resiliency and has driven innovation, on the other hand
understanding its internal mechanisms is a daunting task, made worse by
the fast and constant deployment of new services and applications.
However, behind what it could seem a chaotic scenario, the Internet is composed by
well defined markets in which big players participate having precise
interests:
\begin{description}
\item \textbf{Users}, representing the majority of the people which assess
to the network. They are interested in \emph{Quality of Experience} - QoE, i.e.,
having good performance when accessing to the network, avoiding for example
long delay related to the initial buffering when streaming a video.
They are also interested in the \emph{Network Neutrality}, preserving their freedom
to use the Internet independently from which service they are accessing;
\item \textbf{Internet Service Providers - ISP}, corresponding to
organizations which provide Internet access to the customers.
They are interested in incrementing the revenues through i) \emph{network engineering}
as to optimize the offered services and ii) studying the users' activity
as to find new \emph{billing policies};
\item \textbf{Content providers}, corresponding to organizations
which sell a specific Internet service, e.g., video streaming, file hosting, etc.
As for ISPs, they are interested in finding new way to make revenues.
At the same time, they have to cope also with illegal activities
as \emph{content piracy}, a common flaw since the early days
of peer-to-peer systems;
\item \textbf{Government regulation agencies}, corresponding to
organizations which regulate some aspects of the Internet activities.
For example, they study \emph{Service Level Agreements} - SLA
between users and ISPs, comparing the quality of
the Internet access offered to the users with respect to the specifications
written in the contract signed.
\end{description}
Other activities as \emph{security} are important for more than one
player. Consider for example \emph{malware} and \emph{Denial of Service} - DoS attacks.
These can violate the users' privacy, damaging the network and violate some laws.
Overall then, there are several motivations to be interested in studying the Internet.
Since the early days, the scientific community has made giant steps
toward understanding the Internet. We can generalize
that two requirements have to be satisfied.
First of all, we need \emph{tools and methodologies} as to inspect and characterize the traffic
at different granularities, i.e., per-packet,
per-flow, per-port, per-user, etc.
In particular, \emph{traffic classification} is one of most important activities
performed by network operators. It allows to identify which application has generated
a given communication and to study not only the whole network traffic aggregate
but also how different applications
participate in the composition of the total traffic.
Leveraging on these tools and methodologies, we can further drill into
performing \emph{users and network characterization}. For example,
monitoring the traffic over long-term periods, we can study the
applications' popularity trends and identify the rise of new technologies.
We can perform \emph{anomaly detection}, i.e., study unexpected network
condition that might be related to either security issues of malfunctioning
hardware. We can optimize routing policies, study inter-ISP traffic,
investigate the energy consumption of the network elements or
work on caching schemes related social network content,
just to name a few of the huge amount of research
studies recently conducted in the literature.
In this thesis, we present our contributions in studying the Internet
discussing the tools and methodologies developed to characterize the network traffic.
The thesis is divided in two parts.
In the first part we focus on traffic classification methodologies
starting from the problem definition and the available solutions in the literature
as reported in Chapter~\ref{chapter:traff_class}.
In the remaining of the first part
we focus on KISS, a novel traffic classification
technique we propose based on \emph{Stochastic Packet Inspection} (SPI) analysis.
In particular, in Chapter~\ref{chapter:kiss} we describe the framework used by the classifier
which is then validated in Chapter~\ref{sec:kiss_udp} and~\ref{sec:kiss_tcp} for
UDP and TCP traffic respectively.
Chapter~\ref{chapter:compare} is about the comparison of KISS with other
state of the art traffic classifier while in Chapter~\ref{sec:clustering}
we extend the KISS framework with some clustering techniques.
Overall, KISS allows to reach a high level of accuracy in traffic classification
which is comparable or even better with respect to other traffic classifiers.
It presents a flexible structure which is able to identify a rich set
of applications with a limited amount of resource requirements.
In the second part of the thesis we study YouTube,
the famous video streaming system. Leveraging on Tstat,
a passive traffic analyzer, we developed a methodology
to identify the YouTube video downloads and we conduct
an in depth analysis of many aspects of YouTube.
In Chapter~\ref{sec:yt-overview} we start presenting an
overview of the system and its components showing
the internal mechanisms adopted.
Chapter~\ref{sec:yt-methodology} reports an analysis
of the available methodologies in the literature to
study YouTube and presents our methodology based
on monitoring the real users' activities considering
different location, access technologies and devices.
In the remaining chapters we present the results of our analysis
grouped in four different areas of interest: video content
properties (Chapter~\ref{sec:yt-content}),
internal load balancing and caching policies (Chapter~\ref{sec:yt-cdn}),
users' habits and behaviours (Chapter~\ref{sec:user}), and
download performance (Chapter~\ref{sec:yt-performance}).
Results show that YouTube is a complex system where several
components interact with precise policies used to control
the communications. Besides its great success, the system
is far from being perfect and there is space for further optimization.
For example, mobile devices suffer more impairments during the download
with respect to PCs. Users stick to the default video resolution and are not interested
in changing the quality during the playback. Instead, it is
common the abruptly abort of the download. This behaviour
is particularly critical because, coupled
with aggressive buffering policies used to ensure continuity
in the playback, it leads to waste a non negligible amount of traffic, i.e.,
the users download a portion of the video which it is never played.
2
ROLLO, FEDERICA. "Verso soluzioni di sostenibilità e sicurezza per una città intelligente." Doctoral thesis, Università degli studi di Modena e Reggio Emilia, 2022. http://hdl.handle.net/11380/1271183.
Full textAbstract:
Una città intelligente è un luogo in cui la tecnologia viene sfruttata per aiutare le amministrazioni pubbliche a prendere decisioni. La tecnologia può contribuire alla gestione di numerosi aspetti della vita quotidiana, offrendo ai cittadini servizi più affidabili e migliorando la qualità della vita. Tuttavia, la tecnologia da sola non è sufficiente per rendere una città intelligente; sono necessari metodi adeguati per analizzare i dati raccolti e gestirli in modo da generare informazioni utili. Alcuni esempi di servizi intelligenti sono le app che permettono di raggiungere una destinazione attraverso il percorso più breve oppure di trovare il parcheggio libero più vicino, o le app che suggeriscono i percorsi migliori per una passeggiata in base alla qualità dell'aria.
Questa tesi si concentra su due aspetti delle smart city: sostenibilità e sicurezza.
Il primo aspetto riguarda lo studio dell'impatto del traffico sulla qualità dell'aria attraverso lo sviluppo di una rete di sensori di traffico e qualità dell'aria e l'implementazione di una catena di modelli di simulazione. Questo lavoro fa parte del progetto TRAFAIR, cofinanziato dall'Unione Europea, il primo progetto che monitora la qualità dell'aria in tempo reale e fa previsioni su scala urbana in 6 città europee, tra cui Modena.
Il progetto ha richiesto la gestione di una grande quantità di dati eterogenei e la loro integrazione su una piattaforma dati complessa e scalabile condivisa da tutti i partner del progetto. La piattaforma è un database PostgreSQL, adatto a gestire dati spazio-temporali, che contiene più di 60 tabelle e 435 GB di dati (solo per Modena). Tutti i processi della pipeline di TRAFAIR, le dashboard e le app sfruttano il database per ottenere i dati di input ed eventualmente memorizzare l'output. I modelli di simulazione, eseguiti su risorse di HPC, utilizzano i dati dei sensori e devono fornire risultati in tempo reale. Pertanto le tecniche di identificazione delle anomalie applicate ai dati dei sensori devono eseguire in tempo reale e in breve tempo.
Dopo un attento studio della distribuzione dei dati dei sensori e della correlazione tra le misure, sono state implementate e applicate alcune tecniche di identificazione delle anomalie. Per i dati di traffico è stato sviluppato un nuovo approccio che utilizza un filtro di correlazione flusso-velocità, la decomposizione STL e l'analisi IQR. Per i dati di qualità dell'aria è stato creato un framework innovativo che implementa 3 algoritmi. I risultati degli esperimenti sono stati confrontati con quelli dell'Autoencoder LSTM.
L'aspetto relativo alla sicurezza nella città intelligente è legato a un progetto di analisi dei crimini, i processi analitici volti a fornire informazioni tempestive e pertinenti per aiutare la polizia nella riduzione, prevenzione e valutazione del crimine. A causa della mancanza di dati ufficiali, questo progetto sfrutta le notizie pubblicate sui giornali online. L'obiettivo è quello di classificare le notizie in base alla categoria di crimine, geolocalizzare i crimini, identificare la data dell'evento, e individuare alcune caratteristiche. È stata sviluppata un'applicazione per l'analisi delle notizie, l'estrazione di informazioni semantiche attraverso l'uso di tecniche di NLP e la connessione delle entità a risorse Linked Data. La tecnologia dei Word Embedding è stata utilizzata per la categorizzazione del testo, mentre il Question Answering tramite BERT è stato utilizzato per estrarre le 5W+1H. Le notizie che si riferiscono allo stesso evento sono state identificate attraverso la cosine similarity sul testo delle notizie. Infine, è stata implementata un'interfaccia per mostrare su mappa i crimini geolocalizzati e fornire statistiche e rapporti annuali. Questo è l'unico progetto presente in Italia che partendo da notizie online cerca di fornire un'analisi sui crimini e la mette a disposizione attraverso uno strumento di visualizzazione.A smart city is a place where technology is exploited to help public administrations make decisions. The technology can contribute to the management of multiple aspects of everyday life, offering more reliable services to citizens and improving the quality of life. However, technology alone is not enough to make a smart city; suitable methods are needed to analyze the data collected by technology and manage them in such a way as to generate useful information. Some examples of smart services are the apps that allow to reach a destination through the least busy road route or to find the nearest parking slot, or the apps that suggest better paths for a walk based on air quality. This thesis focuses on two aspects of smart cities: sustainability and safety. The first aspect concerns studying the impact of vehicular traffic on air quality through the development of a network of traffic and air quality sensors, and the implementation of a chain of simulation models. This work is part of the TRAFAIR project, co-financed by the European Union, which is the first project with the scope of monitoring in real-time and predicting air quality on an urban scale in 6 European cities, including Modena. The project required the management of a large amount of heterogeneous data and their integration on a complex and scalable data platform shared by all the partners of the project. The data platform is a PostgreSQL database, suitable for dealing with spatio-temporal data, and contains more than 60 tables and 435 GB of data (only for Modena). All the processes of the TRAFAIR pipeline, the dashboards and the mobile apps exploit the database to get the input data and, eventually, store the output, generating big data streams. The simulation models, executed on HPC resources, use the sensor data and provide results in real-time (as soon as the sensor data are stored in the database). Therefore, the anomaly detection techniques applied to sensor data need to perform in real-time in a short time. After a careful study of the distribution of the sensor data and the correlation among the measurements, several anomaly detection techniques have been implemented and applied to sensor data. A novel approach for traffic data that employs a flow-speed correlation filter, STL decomposition and IQR analysis has been developed. In addition, an innovative framework that implements 3 algorithms for anomaly detection in air quality sensor data has been created. The results of the experiments have been compared to the ones of the LSTM autoencoder, and the performances have been evaluated after the calibration process. The safety aspect in the smart city is related to a crime analysis project, the analytical processes directed at providing timely and pertinent information to assist the police in crime reduction, prevention, and evaluation. Due to the lack of official data to produce the analysis, this project exploits the news articles published in online newspapers. The goal is to categorize the news articles based on the crime category, geolocate the crime events, detect the date of the event, and identify some features (e.g. what has been stolen during the theft). A Java application has been developed for the analysis of news articles, the extraction of semantic information through the use of NLP techniques, and the connection of entities to Linked Data. The emerging technology of Word Embeddings has been employed for the text categorization, while the Question Answering through BERT has been used for extracting the 5W+1H. The news articles referring to the same event have been identified through the application of cosine similarity to the shingles of the news articles' text. Finally, a tool has been developed to show the geolocalized events and provide some statistics and annual reports. This is the only project in Italy that starting from news articles tries to provide analyses on crimes and makes them available through a visualization tool.
3
Wonta, Yonatan. "Performance analysis and modeling of FCIP san traffic in mixed priority IP traffics." Thesis, Wichita State University, 2012. http://hdl.handle.net/10057/5544.
Full textAbstract:
Fibre Channel (FC) is a high-speed data transfer technology used in communication between storage subsystems and computing devices commonly called Storage Area Networks (SAN). A Fibre Channel over TCP/IP enables the connection of FC-SANs isolated by IP networks. This thesis examines the FCIP protocol which is used as FC SAN extensions for SANs geographically separated by Wide Area IP networks. The performance of synchronous mirroring is examined between two SAN islands when operating though an IP network. A mathematical model is developed based on a series of experiments which denotes the characteristics of the FCIP protocol under the presence of varying load mixed IP traffics such as voice and video. The author also investigates performance improvement mechanisms using Multi-Protocol Label Switching (MPLS) and IP Quality of Service (QoS). The application of IP QoS to classify data based on priority is used to differentiate mission-critical applications and to apply the appropriate priority schemes. The use of MPLS enables core networks to function with a packet exchange speed closer to that offered by layer 2 switching. This thesis presents a comparison of the real time values against the modeled values. The performance boost observed using IP QoS and MPLS is also presented in this study.Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science
4
GRIMAUDO, LUIGI. "Data Mining Algorithms for Internet Data: from Transport to Application Layer." Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2537089.
Full textAbstract:
Nowadays we live in a data-driven world. Advances in data generation, collection and storage technology have enabled organizations to gather data sets of massive size. Data mining is a discipline that blends traditional data analysis methods with sophisticated algorithms to handle the challenges posed by these new types of data sets.
The Internet is a complex and dynamic system with new protocols and applications that arise at a constant pace. All these characteristics designate the Internet a valuable and challenging data source and application domain for a research activity, both looking at Transport layer, analyzing network tra c flows, and going up to Application layer, focusing on the ever-growing next generation web services: blogs, micro-blogs, on-line social networks, photo sharing services and many other applications (e.g., Twitter, Facebook, Flickr, etc.).
In this thesis work we focus on the study, design and development of novel algorithms and frameworks to support large scale data mining activities over huge and heterogeneous data volumes, with a particular focus on Internet data as data source and targeting network tra c classification, on-line social network analysis, recommendation systems and cloud services and Big data.
5
Lindberg, Gunnar. "Valuation and pricing of traffic safety /." Örebro : Universitetsbiblioteket : Örebro University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-787.
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Caldwell, Sean W. "On Traffic Analysis of 4G/LTE Traffic." Cleveland State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=csu1632179249187618.
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Ruffing, Nicholas Luke. "Analysis of Smartphone Traffic." Cleveland State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=csu1430150923.
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Wegner, Douglas Michael. "AMCROSS message traffic analysis." Master's thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-12232009-020318/.
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De, Albuquerque Filho Emilio Alverne Falcão. "Analysis of airspace traffic structure and air traffic control techniques." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/76097.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 157-163).
Air traffic controller cognitive processes are a limiting factor in providing safe and efficient flow of traffic. Therefore, there has been work in understanding the factors that drive controllers decision-making processes. Prior work has identified that the airspace structure, defined by the reference elements, procedural elements and pattern elements of the traffic, is important for abstraction and management of the traffic. This work explores in more detail this relationship between airspace structure and air traffic controller management techniques. This work looks at the current National Airspace System (NAS) and identifies different types of high altitude sectors, based on metrics that are likely to correlate with tasks that controllers have to perform. Variations of structural patterns, such as flows and critical points were also observed. These patterns were then related to groupings by origins and destinations of the traffic. Deeper pilot-controller voice communication analysis indicated that groupings by flight plan received consistent and repeatable sequences of commands, which were identified as techniques. These repeated modifications generated patterns in the traffic, which were naturally associated with the standard flight plan groupings and their techniques. The identified relationship between flight plan groupings and management techniques helps to validate the grouping structure-base abstraction introduced by Histon and Hansman (2008). This motivates the adoption of a grouping-focused analysis of traffic structures on the investigation of how new technologies, procedures and concepts of operations will impact the way controllers manage the traffic. Consideration of such mutual effects between structure and controllers' cognitive processes should provide a better foundation for training and for engineering decisions that include a human-centered perspective.
by Emilio Alverne Falcão de Albuquerque Filho.
S.M.
10
Shi, Ping. "WWW traffic analysis and simulation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ35527.pdf.
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Liu, Wei 1975. "Network traffic modelling and analysis." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82613.
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In all-photonic networks, both transmission and switching is performed in the optical domain, without optoelectronic conversion for the data traversing the network. An accurate traffic model is critical in an agile all-photonic network (AAPN) which has the ability to dynamically allocate bandwidth to traffic flows as the demand varies.This thesis focuses on traffic modelling and analysis. A novel traffic model is proposed which can capture the traffic behaviours in all-photonic networks. The new model is based on a study of existing traffic modelling literature. It combines the time-varying Poisson model, gravity model and fractional Gaussian noise. This model can be used for the short-range traffic prediction. We examine Long-Range Dependence and test the time constancy of scaling parameters using the tools designed by Abry and Veitch, to analyze empirical and synthesized traffic traces.
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Simhairi, Nather Zeki. "Traffic assignment and network analysis." Thesis, Royal Holloway, University of London, 1987. http://repository.royalholloway.ac.uk/items/a3377f99-4ed8-4000-91f8-0384aed4a3c6/1/.
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This thesis studies the transportation network, and is divided into three sections. Initially an algorithm is described which finds the user-equilibrium assignment for networks with linear congestion functions where the cost of travel on a link is dependent on the flow in the whole network. Secondly it investigates the sensitivity of the cost of travel and of the flow distribution in the network, to changes in the link congestion function. Combinatorial methods are used for evaluating the results of the sensitivity analysis. This is done with the aim of obtaining fast and efficient algorithms for the evaluation of cost sensitive and paradoxical links. Finally, for networks where the demand is elastic, it describes the catastrophic behaviour of the point representing the user-equilibrium flow distribution under certain cost conditions.
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Zhou, Xiao Yi. "Statistical analysis of traffic loads and traffic load effects on bridges." Phd thesis, UNIVERSITE PARIS-EST, 2013. http://tel.archives-ouvertes.fr/tel-00949929.
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Une grande majorité (85%) des ponts français a une portée inférieure à 50 m. Pour ce type d’ouvrage d’art, la charge de trafic peut être déterminante pour la conception et le recalcul. Or, en Europe, le fret routier a augmenté de 36.2% entre 1995 et 2010, et la croissance annuelle du volume transporté par la route a été évaluée à 1.7% entre 2005 et 2030. Il est donc essentiel de s’assurer que les infrastructures européennes sont en mesure de répondre à cette demande croissante en capacité structurelle des ouvrages. Pour les ouvrages neufs, les modèles de trafic dans les normes ou les législations pour la conception des ponts incluent une marge de sécurité suffisante pour que la croissance du trafic soit prise en compte sans dommage par ces ouvrages. Mais pour les ouvrages existants, la résistance structurelle aux trafics actuels et futur est à vérifier et une priorisation des mesures doit être faite pour assurer leur intégrité structurelle et leur sécurité. De plus, afin de préserver leur infrastructure tout en ne menaçant pas leur compétitivité nationale, certains pays réfléchissent à l’introduction de poids lourds plus longs, plus lourds, ce qui permet de réduire le nombre de véhicules pour un volume ou un tonnage donné, ainsi que d’autres coûts (d’essence, de travail, ..), ce qui justifie encore plus les calculs effectués. Pour répondre à ce genre de problématique, différentes méthodes d’extrapolation ont déjà été utilisées pour modéliser les effets extrêmes du trafic, afin de déterminer les effets caractéristiques pour de grandes périodes de retour. Parmi celles-ci nous pouvons citer l’adaptation d’une gaussienne ou d’une loi de Gumbel sur la queue de distribution empirique, la formule de Rice appliquée à l’histogramme des dépassements de niveaux, la méthode des maxima par blocs ou celle des dépassements de seuils élevés. Les fondements et les utilisations faites de ces méthodes pour modéliser les effets extrêmes du trafic sur les ouvrages sont donnés dans un premier chapitre. De plus, une comparaison quantitative entre ces méthodes est réalisée. Deux études sont présentées, l’une basée sur un échantillon numérique et l’autre sur un échantillon réaliste d’effets du trafic. L’erreur induite par ces méthodes est évaluée à l’aide d’indicatifs statistiques simples, comme l’écart-type et les moindres carrés, évalués sur les valeurs caractéristiques et les probabilités de rupture. Nos conclusions sont, qu’en général, les méthodes sont moins précises lorsqu’il s’agit de déterminer des probabilités de rupture que lorsqu’elles cherchent des valeurs caractéristiques. Mais la raison peut en être les faibles probabilités recherchées (10-6 par an). De plus, bien qu’aucune méthode n’ait réalisée des extrapolations de manière correcte, les meilleures sont celles qui s’intéressent aux queues de probabilités, et en particulier des dépassements au-dessus d’un seuil élevé. Ainsi une étude de cette dernière méthode est réalisée : en effet, cette méthode, nommé "dépassements d’un seuil élevé", considère que les valeurs au-dessus d’un seuil correctement choisi, assez élevé, suit une distribution de Pareto généralisée (GPD). Cette méthode est utilisée de manière intensive dans les domaines de l’hydrologie et la finance, mais non encore appliquée dans le domaine des effets du trafic sur les ouvrages. Beaucoup de facteurs influencent le résultat lorsqu’on applique cette méthode, comme la quantité et la qualité des données à notre disposition, les critères utilisés pour déterminer les pics indépendants, l’estimation des paramètres et le choix du seuil. C’est pour cette raison qu’une étude et une comparaison des différentes méthodes d’estimation des paramètres de la distribution GPD sont effectuées : les conditions, hypothèses, avantages et inconvénients des différentes méthodes sont listés. Différentes méthodes sont ainsi étudiées, telles la méthode des moments (MM), la méthode des moments à poids (PWM), le maximum de vraisemblance (ML), le maximum de vraisemblance pénalisé (PML), le minimum de la densité de la divergence (MDPD), la méthode des fractiles empiriques (EPM), la statistique du maximum d’adaptation et la vraisemblance des moments (LM). Pour comparer ces méthodes, des échantillons numériques, des effets de trafic simulés par Monte Carlo et des effets mesurés sur un ouvrage réel sont utilisés. Comme prévu, les méthodes ont des performances différentes selon l’échantillon considéré. Néanmoins, pour des échantillons purement numériques, MM et PWM sont recommandées pour des distributions à paramètre de forme négatif et des échantillons de petite taille (moins de 200 valeurs). ML est conseillé pour des distributions à paramètre de forme positif. Pour des effets du trafic simulés, ML et PML donne des valeurs de retour plus correctes lorsque le nombre de valeurs au-dessus du seuil est supérieur à 100 ; dans le cas contraire, MM et PWM sont conseillés. De plus, comme c’est prouvé dans l’étude de valeurs réelles mesurées, les valeurs a priori aberrantes ("outliers") ont une influence notable sur le résultat et toutes les méthodes sont moins performantes. Comme cela a été montré dans la littérature, ces "outliers" proviennent souvent du mélange de deux distributions, qui peuvent être deux sous-populations. Dans le cas de l’effet du trafic sur les ouvrages, cela peut être la raison d’une estimation des paramètres non correcte. Les articles existant sur le sujet soulignent le fait que les effets du trafic sont dus à des chargements indépendants, qui correspondant au nombre de véhicules impliqués. Ils ne suivent pas la même distribution, ce qui contredit l’hypothèse classique en théorie des valeurs extrêmes que les événements doivent être indépendants et identiquement distribués. Des méthodes permettant de prendre en compte ce point et utilisant des distributions mélangées (exponentielles ou valeurs extrêmes généralisées) ont été proposées dans la littérature pour modéliser les effets du trafic. Nous proposons une méthode similaire, que nous appelons dépassement de seuils mélangés, afin de tenir des différentes distributions sous-jacentes dans l’échantillon tout en appliquant à chacune d’entre elles la méthode des dépassements de seuil. Pour des ponts ayant des portées supérieures à 50 m, le scénario déterminant est celui de la congestion, qui n’est pas ce qui est étudié ici. De plus, le trafic n’est pas la composante déterminante pour la conception des ponts de longue portée. Mais des problèmes de fatigue peuvent apparaître dans certains ponts, tels les ponts métalliques à dalle orthotrope, où l’étude du trafic peut devenir nécessaire. Ainsi nous avons fait une étude de l’influence de la position des véhicules sur le phénomène de fatigue. Pour cela, quatre fichiers de trafic réels, mesurés en 2010 et 2011 par quatre stations de pesage différentes, ont été utilisés. Ils ont mis à jour des comportements latéraux différents d’une station à l’autre. Si nous les appliquons au viaduc de Millau, qui est un pont métallique à haubans et à dalle orthotrope, nous voyons que l’histogramme des effets et l’effet de fatigue cumulé est beaucoup affecté par le comportement latéral des véhicules. Ainsi, des études approfondies utilisant les éléments finis pour modéliser les ouvrages et des enregistrements de trafic réel, peuvent être utilisées pour pré-déterminer quels éléments, donc quelles soudures, doivent être examinés dans les ponts afin d’estimer leur santé structurelle.
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Saad, Soha. "Méthodologie de réorganisation du trafic ferroviaire par analyse de sensibilité régionale : application à un incident sur infrastructure électrique." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAI057/document.
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La qualité d'alimentation électrique d'un réseau ferroviaire peut être fortement affectée par l'indisponibilité d'un équipement électrique, que ce soit suite à un incident technique ou une opération de maintenance. Il est alors nécessaire de réduire le trafic prévu en ajustant les grilles horaires et les profils de vitesse, tout en conservant des performances d'exploitation optimales. Le but du travail présenté dans ce mémoire est de développer un outil d'aide à la décision pour assister les agents en charge de la réorganisation du trafic lors d'un incident sur infrastructure électrique. Le système étudié est complexe et son analyse repose sur des simulations coûteuses. Nous avons donc proposé une démarche en deux phases. Dans un premier temps, une analyse de sensibilité permet de détecter de manière efficace les variables d’ajustement du trafic les plus influentes. Après une analyse comparative entre différentes techniques, nous avons retenu l’analyse de sensibilité régionale par filtrage de Monte Carlo et test de KS, car cela permet de prendre en compte les contraintes opérationnelles, comme les niveaux de tension en ligne. La deuxième phase consiste à optimiser la solution en travaillant dans un espace de recherche de dimension réduite. Un ensemble de solutions Pareto optimales sont générées afin d’évaluer le meilleur compromis entre le critère principal qui est la densité de trafic et d’autres critères tels que les pertes ou les échauffements. Les techniques mises en œuvre ont abouti à la réalisation d’un prototype. Cet outil permet à l’ingénieur de définir les variables d’ajustement et les critères de performance du trafic. Il analyse ensuite l’influence des différentes variables d’ajustement et optimise le trafic par rapport aux critères définis. L’outil a été testé sur quatre cas d’étude correspondant à des portions de réseaux et à des trafics ferroviaires réelsThe power supply quality of a railway network can be strongly affected by the unavailability of electrical equipment, whether due to a technical incident or a maintenance operation. It is then necessary to reduce the expected traffic by adjusting the time schedules and speed profiles, while maintaining optimal operating performance. The purpose of the work presented in this thesis is to develop a decision support tool to assist the agents in charge of the reorganization of traffic during an incident on electrical infrastructure. The studied system is complex and its analysis is based on costly simulations. We therefore proposed a two-phase approach. As a first step, a sensitivity analysis can effectively detect the most influential traffic adjustment variables. After a comparative analysis between different techniques, we selected the regional sensitivity analysis by Monte Carlo filtering and KS test, because it allows us to take into account the operational constraints, like the tension levels in line. The second phase consists in optimizing the solution by working in a small research area. A set of Pareto-Optimal solutions are generated to evaluate the best trade-off between the main criterion "traffic density" and other criteria such as losses or overheating. The techniques implemented led to the production of a prototype. The tool allows the engineer to define traffic adjustment variables and traffic performance criteria. Then it analyzes the influence of the various adjustment variables and optimizes the traffic according to the defined criteria. The tool was tested on four case studies proposed by SNCF Réseau and corresponding to network segments and actual rail traffic
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Shbair, Wazen M. "Service-Level Monitoring of HTTPS Traffic." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0029/document.
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Dans cette thèse, nous dressons tout d'abord un bilan des différentes techniques d'identification de trafic et constatons l'absence de solution permettant une identification du trafic HTTPS à la fois précise et respectueuse de la vie privée des utilisateurs. Nous nous intéressons dans un premier temps à une technique récente, néanmoins déjà déployée, permettant la supervision du trafic HTTPS grâce à l'inspection du champ SNI, extension du protocole TLS. Nous montrons que deux stratégies permettent de contourner cette méthode. Comme remédiation, nous proposons une procédure de vérification supplémentaire basée sur un serveur DNS de confiance. Les résultats expérimentaux montrent que cette solution pragmatique est efficace. Ensuite, nous proposons une architecture qui permet l'identification des services dans le trafic HTTPS, en se basant sur l'apprentissage automatique. Nous avons ainsi défini un nouvel ensemble de caractéristiques statistiques combinées avec une identification à deux niveaux, identifiant d'abord le fournisseur de services, puis le service, selon notre évaluation à partir de trafic réel. Enfin, nous améliorons cette architecture afin de permettre l'identification du trafic en temps réel en ne considérant que les premiers paquets des flux plutôt que leur totalité. Pour évaluer notre approche, nous avons constitué un dataset comportant les flux complets de chargement des principaux sites web et l'avons rendu public pour comparaison. Nous présentons également un prototype de logiciel reconstituant les flux HTTPS en temps réel puis les identifiantIn this thesis, we provide a privacy preserving for monitoring HTTPS services. First, we first investigate a recent technique for HTTPS services monitoring that is based on the Server Name Indication (SNI) field of the TLS handshake. We show that this method has many weakness, which can be used to cheat monitoring solutions.To mitigate this issue, we propose a novel DNS-based approach to validate the claimed value of SNI. The evaluation show the ability to overcome the shortage. Second, we propose a robust framework to identify the accessed HTTPS services from a traffic dump, without relying neither on a header field nor on the payload content. Our evaluation based on real traffic shows that we can identify encrypted HTTPS services with high accuracy. Third, we have improved our framework to monitor HTTPS services in real-time. By extracting statistical features over the TLS handshake packets and a few application data packets, we can identify HTTPS services very early in the session. The obtained results and a prototype implementation show that our method offers good identification accuracy, high HTTPS flow processing throughput, and a low overhead delay
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Fu, Xinwen. "On traffic analysis attacks and countermeasures." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4968.
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Security and privacy have gained more and more attention with the rapid growth and
public acceptance of the Internet as a means of communication and information
dissemination. Security and privacy of a computing or network system may be
compromised by a variety of well-crafted attacks.
In this dissertation, we address issues related to security and privacy in computer
network systems. Specifically, we model and analyze a special group of network attacks,
known as traffic analysis attacks, and develop and evaluate their countermeasures.
Traffic analysis attacks aim to derive critical information by analyzing traffic over a
network. We focus our study on two classes of traffic analysis attacks: link-load analysis
attacks and flow-connectivity analysis attacks.
Our research has made the following conclusions:
1. We have found that an adversary may effectively discover link load by passively
analyzing selected statistics of packet inter-arrival times of traffic flows on a
network link. This is true even if some commonly used countermeasures (e.g.,
link padding) have been deployed. We proposed an alternative effective countermeasure to counter this passive traffic analysis attack. Our extensive
experimental results indicated this to be an effective approach.
2. Our newly proposed countermeasure may not be effective against active traffic
analysis attacks, which an adversary may also use to discover the link load. We
developed methodologies in countering these kinds of active attacks.
3. To detect the connectivity of a flow, an adversary may embed a recognizable
pattern of marks into traffic flows by interference. We have proposed new
countermeasures based on the digital filtering technology. Experimental results
have demonstrated the effectiveness of our method.
From our research, it is obvious that traffic analysis attacks present a serious
challenge to the design of a secured computer network system. It is the objective of this
study to develop robust but cost-effective solutions to counter link-load analysis attacks
and flow-connectivity analysis attacks. It is our belief that our methodology can provide
a solid foundation for studying the entire spectrum of traffic analysis attacks and their
countermeasures.
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Billot, Romain. "Analyse et modélisation de l'impact de la météorologie sur le trafic routier." Phd thesis, Ecole Centrale Paris, 2010. http://tel.archives-ouvertes.fr/tel-00557812.
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Si la pertinence de la prise en compte de la météorologie dans la gestion du trafic est bien admise, son intégration dans les outils d'aide à la décision et les stratégies de contrôle représente encore un enjeu réel pour les gestionnaires d'infrastructures. En effet, cette avancée semble légitimée par les effets significatifs d'une météorologie dégradée sur la sécurité des usagers et le comportement des conducteurs. Ainsi, au niveau de la sécurité, un sur-risque d'accident a été mis en évidence par de nombreux travaux. Or, l'étiologie de ce risque augmenté ne permet pas seulement de démontrer l'impact d'évènements météorologiques extrêmes et ponctuels (ex : tempêtes de neige), mais égalementcelui de phénomènes récurrents (ex : la pluie). La baisse de la sécurité des conducteurs se traduit concrètement par un changement de comportements des usagers (vitesses, temps inter-véhiculaires) mais aussi du flot de véhicules en général (vitesse, débit, concentration), ceci influant de manière conséquente sur la mobilité. De fait, la pluie représente ainsi la seconde cause de congestion ponctuelle.Pourtant, malgré ces enjeux indéniables, les effets de la météorologie sur le trafic demeurent mal quantifiés et ne sont guère intégrés à la modélisation ou l'estimation du trafic. Ce travail de thèse se propose ainsi de contribuer à une meilleure compréhension des effets météorologiques sur le trafic, en se focalisant sur des phénomènes de précipitations en milieu interurbain. Partant d'un état de l'art de l'impact météorologique sur le trafic, il nous est apparu que les études existantes, par leurs carences, soulèvent le besoin de fonder une méthodologie d'analyse plus rigoureuse. Cette méthodologie, une fois clairement définie, a ensuite été appliquée à des données opérationnelles. Elle nous a permis de quantifier les effets de la pluie à plusieurs niveaux selon l'échelle de représentation abordée : au niveau microscopique, considérant le comportement individuel des conducteurs, les analyses statistiques mettent en lumière des effets sur les vitesses, les temps et les distances inter-véhiculaires. Ces effets se reflètent au niveau macroscopique (celui du flot de véhicules) avec des variations de débits, de vitesses du flot et, de façon générale, de l'ensemble des paramètres formant le diagramme fondamental du trafic. Les résultats empiriques nous semblent ainsi ouvrir la voie à l'intégration du phénomène météorologique à la modélisation du trafic.Partant, nous avons développé, à ce stade de notre travail, une contribution théorique à la modélisation du trafic se fondant sur une formulation Vlasov qui permet de dériver un modèle macroscopique à deux équations à partir d'une formulation cinétique. Le modèle ainsi proposé offre un cadre propice à l'intégration d'un paramètre météorologique. La discrétisation numérique du modèle s'effectue à l'aide d'une méthode à pas fractionnaire qui permet de traiter successivement le terme source et la partie homogène du système. Pour la partie homogène du système, nous avons fait l'usage d'un schéma de type Lagrange+remap. Le comportement du modèle, couplé à une équation de transport sur les temps inter-véhiculaires, a ensuite été illustré à travers une série d'expérimentations numériques qui ont mis en évidence ses aptitudes face à des conditions météorologiques changeantes.Dans un ultime volet, notre travail s'est orienté vers de futures applications en temps réel qui se placeraient dans un cadre bayesien d'assimilation de données. Le défi à relever est celui de l'estimation en ligne du vecteur d'état du trafic au fur et à mesure de l'arrivée de nouvelles observations. Une méthode de filtrage particulaire (Monte Carlo séquentielle) nous a paru judicieuse à mobiliser, car elle s'adapte bien à la problématique du trafic routier. Plusieurs scénarios fondés sur des données opérationnelles permettent ensuite de montrer les bénéfices de l'intégration du phénomène météorologique à de telles approches. Une meilleure connaissance du phénomène météorologique doit ainsi mener à son insertion dans les modèles de trafic qui forment le substrat des outils d'aide à la décision destinés aux gestionnaires.Le travail proposé ouvre donc des perspectives pour le développement de stratégies de gestion de trafic météo-sensibles.
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Wu, Chi-Hung Evelyn. "Causal analysis of highway crashes : a systematic analysis approach with subjective and statistical methods." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/20030.
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Liu, Jian. "Fractal Network Traffic Analysis with Applications." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/11477.
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Today, the Internet is growing exponentially, with traffic statistics that mathematically exhibit fractal characteristics: self-similarity and long-range dependence. With these properties, data traffic shows high peak-to-average bandwidth ratios and causes networks inefficient. These problems make it difficult to predict, quantify, and control data traffic. In this thesis, two analytical methods are used to study fractal network traffic. They are second-order self-similarity analysis and multifractal analysis.
First, self-similarity is an adaptability of traffic in networks. Many factors are involved in creating this characteristic. A new view of this self-similar traffic structure related to multi-layer network protocols is provided. This view is an improvement over the theory used in most current literature.
Second, the scaling region for traffic self-similarity is divided into two timescale regimes: short-range dependence (SRD) and long-range dependence (LRD). Experimental results show that the network transmission delay separates the two scaling regions. This gives us a physical source of the periodicity in the observed traffic. Also, bandwidth, TCP window size, and packet size have impacts on SRD. The statistical heavy-tailedness (Pareto shape parameter) affects the structure of LRD. In addition, a formula to estimate traffic burstiness is derived from the self-similarity property.
Furthermore, studies with multifractal analysis have shown the following results. At large timescales, increasing bandwidth does not improve throughput. The two factors affecting traffic throughput are network delay and TCP window size. On the other hand, more simultaneous connections smooth traffic, which could result in an improvement of network efficiency. At small timescales, in order to improve network efficiency, we need to control bandwidth, TCP window size, and network delay to reduce traffic burstiness. In general, network traffic processes have a Hlder exponent a ranging between 0.7 and 1.3. Their statistics differ from Poisson processes.
From traffic analysis, a notion of the efficient bandwidth, EB, is derived. Above that bandwidth, traffic appears bursty and cannot be reduced by multiplexing. But, below it, traffic is congested. An important finding is that the relationship between the bandwidth and the transfer delay is nonlinear.
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Jiang, Michael Zhonghua. "Analysis of wireless data network traffic." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0012/MQ61444.pdf.
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Seshadri, Srikanth R. "Traffic noise analysis at highway underpasses." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1176399213.
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Rigolli, Marco. "Perception of intent : traffic scenes analysis." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433328.
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Heller, Mark D. "Behavioral analysis of network flow traffic." Thesis, Monterey, California. Naval Postgraduate School, 2010. http://hdl.handle.net/10945/5108.
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Approved for public release, distribution unlimitedNetwork Behavior Analysis (NBA) is a technique to enhance network security by passively monitoring aggregate traffic patterns and noting unusual action or departures from normal operations. The analysis is typically performed offline, due to the huge volume of input data, in contrast to conventional intrusion prevention solutions based on deep packet inspection, signature detection, and real-time blocking. After establishing a benchmark for normal traffic, an NBA program monitors network activity and flags unknown, new, or unusual patterns that might indicate the presence of a potential threat. NBA also monitors and records trends in bandwidth and protocol use. Computer users in the Department of Defense (DoD) operational networks may use Hypertext Transport Protocol (HTTP) to stream video from multimedia sites like youtube.com, myspace.com, mtv.com, and blackplanet.com. Such streaming may hog bandwidth, a grave concern, given that increasing amounts of operational data are exchanged over the Global Information Grid, and introduce malicious viruses inadvertently. This thesis develops an NBA solution to identify and estimate the bandwidth usage of HTTP streaming video traffic entirely from flow records such as Cisco's NetFlow data.
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Lam, Wa-Kwai. "Risk analysis and traffic signal design." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328239.
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Ali, Abdulamer T. "Computer vision aided road traffic analysis." Thesis, University of Bristol, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333953.
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Tian, Zhili 1965. "Capacity analysis of traffic-actuated intersections." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/84842.
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Thesis (S.M. in Transportation)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2002.Includes bibliographical references (p. 84-86).
by Zhili Tian.
S.M.in Transportation
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Ouafi, Rachid. "Analyse et contrôle des réseaux de trafic urbain par la méthode de Frank-Wolfe." Paris 6, 1988. http://www.theses.fr/1988PA066453.
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La méthode de Frank Wolfe offre une approche efficace pour la résolution des programmes convexes avec contraintes linéaires. Dans le contexte des réseaux de transport l'algorithme se réduit à une série de problèmes de plus court chemin et de recherches unidimensionnelles. Nous présentons une approche unifiée de la résolution d'une large variété de problèmes lies au système de planification du trafic urbain par la méthode de Frank Wolfe. Enfin, nous proposons une modification de l'algorithme de Frank Wolfe pour la résolution du problème de l'affectation du trafic urbain.
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Sun, Jie. "Locality of Internet Traffic : An analysis based upon traffic in an IP access network." Thesis, KTH, Kommunikationssystem, CoS, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-107686.
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The rapid growth of Internet Traffic has emerged as a major issue due to the rapid development of various network applications and Internet services. One of the challenges facing Internet Service Providers (ISPs) is to optimize the performance of their networks in the face of continuously increasing amounts of IP traffic while guaranteeing some specific Quality of Services (QoS). Therefore it is necessary for ISPs to study the traffic patterns and user behaviors in different localities, to estimate the application usage trends, and thereby to come up with solutions that can effectively, efficiently, and economically support their users’ traffic. The main objective of this thesis is to analyze and characterize traffic in a local multi-service residential IP network in Sweden (referred to in this report as “Network North”). The data about the amount of traffic was measured using a real-time traffic-monitoring tool from PacketLogic. Traffic from the monitored network to various destinations was captured and classified into 5 ring-wise locality levels in accordance with the traffic’s geographic destinations: traffic within Network North and traffic to the remainder of the North of Sweden, Sweden, Europe, and World. Parameters such as traffic patterns (e.g., traffic volume distribution, application usage, and application popularity) and user behavior (e.g., usage habits, user interests, etc.) at different geographic localities were studied in this project. As a result of a systematic and in-depth measurement and the fact that the number of content servers at the World, Europe, and Sweden levels are quite large, we recommend that an intelligent content distribution system be positioned at Level 1 localities in order to reduce the amount of duplicate traffic in the network and thereby removing this traffic load from the core network. The results of these measurements provide a temporal reference for ISPs of their present traffic and should allow them to better manage their network. However, due to certain circumstances the analysis was limited due to the set of available daily traffic traces. To provide a more trustworthy solution, a relatively longer-term, periodic, and seasonal traffic analysis could be done in the future based on the established measurement framework.Den ökande tillväxten av Internet Trafik har blivit en viktig fråga med anledning av den snabba utvecklingen av olika internetbaserade applikationer och tjänster. En av utmaningarna för Internet leverantörerna är att optimera prestandan i sina nät inför de ständigt ökande datamängderna och samtidigt garantera kvalitet på tjänsterna (QoS). Därför är det nödvändigt för Internetleverantörer att studera trafikmönster och lokala differentierade användarbeteenden, för att uppskatta trender av nyttjande av internettjänster, och därmed komma med lösningar som effektivt och ekonomiskt stödja deras kunders trafik. Det främsta syftet med denna avhandling är att analysera och karaktärisera internettrafiken i ett lokalt IP baserat multiservicenätverk i Sverige (i denna rapport avseende "Network North"). Uppgifterna om trafikmängden mättes i realtid med ett övervakningsverktyg från PacketLogic. Trafik till och från det övervakade nätverkets olika destinationer fångades upp och delades in i 5 cirkelliknande lokaliseringsnivåer i enlighet med geografiska trafikdestinationer: trafik inom nätverket North och till resten av norra Sverige, Sverige, Europa och världen. Parametrar som trafikmönster (t.ex. distribuerad internettrafik mängd, användning av olika tjänster och applikationer med dess popularitet) och användarbeteenden (t.ex. användar-vanor och intressen, etc.) på olika geografiska lokaliseringsnivåer har studerades i inom projekt. Som ett resultat av de systematiska och djupgående internetmätningar med det faktum av det stora antalet existerande tjänsteinnehållsservrar som ofta finns placerad långt ifrån slutanvändaren, ute i världen eller i Europa som är ganska så många till antalet. Rekommenderar vi att ett intelligent tjänstedistributionssystem appliceras närmre slutanvändaren på en regional nivå, för att minska på dagens onödiga omfattande duplicerande internettrafik i nom stamnäteten. Resultaten av dessa trafikmätningar av internettrafik ger en tidsmässig referens för Internetleverantörerna av deras nuvarande trafik och bör göra det möjligt för dem att bättre hantera sin nätverksinfrastruktur. Men på grund av vissa omständigheter begränsades mätanalysen på grund av möjliga och tillgängliga tidrammar att utföra dagliga trafikmätningsuppsättningen. För att ge en mer tillförlitlig lösning kan en på en längre sikt, periodisk och säsongsbunden trafikanalys göras i framtiden, baserat på den etablerade mätinfrastrukturen.
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MARELLA, ANDREA. "Metodi innovativi di monitoraggio e di analisi di dati di traffico per la soluzione di problemi di ottimizzazione stocastica di impianti semaforici coordinati." Doctoral thesis, Università degli studi di Genova, 2021. http://hdl.handle.net/11567/1034676.
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Lo sviluppo dell’informatica e l’implementazione dei progetti di Smart City hanno permesso in pochi anni di disporre di un’enorme quantità di dati. Come mettere a frutto queste informazioni è l’obiettivo del presente lavoro. Il campo dell’Intelligent Transportation Systems (ITS) è uno dei settori nel quale la ricerca sui nuovi dati, combinata con l’Artificial Intelligent (AI), ha iniziato a mostrare risultati interessanti. L’ITS permette di fornire servizi innovativi e avanzati relativi alle modalità di trasporto e gestione del traffico e consente agli utenti di fare scelte più intelligenti quando utilizzano le reti di trasporto. Questo ha effetto diretto sull'efficacia dell'infrastruttura nelle città intelligenti urbane.
La ricerca scientifica nel settore del traffico e dei trasporti ha messo a disposizione big data sul traffico in modo diretto con la necessità di studiare modelli di analisi e di rappresentazione dei dati che vanno oltre alla classica modellistica (c.d. simulation agent model based). Grazie ai big data sul traffico e le tecniche di IA e Machine Learning (ML) è oggi possibile studiare nuovi modelli di previsione dei comportanti degli utenti della strada (c.d. data-driven models).
Questo lavoro vuole essere un concreto esempio dell’utilizzo di differenti sistemi innovativi di monitoraggio dei dati di traffico, di modelli di traffico e di ottimizzazione applicati in un caso reale. Le intersezioni semaforizzate analizzate sono state oggetto di una campagna di monitoraggio di video aereo con innovativa strumentazione, dell’applicazione di software di computer vision ed elaborazione dei dati di traffico, di elaborazione di dati FCD, e, infine, di risoluzione di un problema di programmazione stocastica per il coordinamento ottimale.
Nella stesura dell’elaborato, trattandosi di uno studio misto di ricerca applicata e di un caso reale, è stata orientata più possibile al mantenimento di un forte contatto con il campo professionale e di reale applicabilità dei risultati.The development of information technology and the implementation of smart city projects have made it possible in a few years to have an enormous amount of data. How to put this information to good use is the goal of this work. The field of Intelligent Transportation Systems (ITS) is one of the areas in which research on new data, combined with Artificial Intelligent (AI), has begun to show interesting results. ITS allows for the provision of innovative and advanced services relating to modes of transport and traffic management and allows users to make smarter choices when using transport networks. This has a direct effect on the effectiveness of the infrastructure in urban smart cities. Scientific research in the traffic and transport sector has made big data on traffic available directly with the need to study models of analysis and representation of data that go beyond the classic modeling (so-called simulation agent model based). Thanks to big data on traffic and AI and Machine Learning (ML) techniques, it is now possible to study new models for predicting the behavior of road users (so-called data-driven models). This work is intended to be a concrete example of the use of different innovative systems for monitoring traffic data, traffic models and optimization applied in a real case. The traffic light intersections analyzed were the subject of an aerial video monitoring campaign with innovative instrumentation, the application of computer vision software and traffic data processing, FCD data processing, and, finally, the resolution of a problem of stochastic programming for optimal coordination. In drafting the paper, since it was a mixed study of applied research and a real case, it was oriented as much as possible to maintaining a strong contact with the professional field and real applicability of the results.
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Vigneri, Luigi. "Les véhicules comme un mobile cloud : modélisation, optimisation et analyse des performances." Thesis, Université Côte d'Azur (ComUE), 2017. http://www.theses.fr/2017AZUR4055/document.
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La prolifération des appareils portables mène à une croissance du trafic mobile qui provoque une surcharge du cœur du réseau cellulaire. Pour faire face à un tel problème, plusieurs travaux conseillent de stocker les contenus (fichiers et vidéos) dans les small cells. Dans cette thèse, nous proposons d'utiliser les véhicules comme des small cells mobiles et de cacher les contenus à bord, motivés par le fait que la plupart d'entre eux pourra facilement être équipée avec de la connectivité et du stockage. L'adoption d'un tel cloud mobile réduit les coûts d'installation et de maintenance et présente des contraintes énergétiques moins strictes que pour les small cells fixes. Dans notre modèle, un utilisateur demande des morceaux d'un contenu aux véhicules voisins et est redirigé vers le réseau cellulaire après une deadline ou lorsque son playout buffer est vide. L'objectif du travail est de suggérer à un opérateur comment répliquer de manière optimale les contenus afin de minimiser le trafic mobile dans le cœur du réseau. Les principales contributions sont : (i) Modélisation. Nous modélisons le scénario ci-dessus en tenant compte de la taille des contenus, de la mobilité et d'un certain nombre d'autres paramètres. (ii) Optimisation. Nous formulons des problèmes d'optimisation pour calculer les politiques d'allocation sous différents modèles et contraintes. (iii) Analyse des performances. Nous développons un simulateur MATLAB pour valider les résultats théoriques. Nous montrons que les politiques de mise en cache proposées dans cette thèse sont capables de réduire de plus que 50% la charge sur le cœur du réseau cellulaireThe large diffusion of handheld devices is leading to an exponential growth of the mobile traffic demand which is already overloading the core network. To deal with such a problem, several works suggest to store content (files or videos) in small cells or user equipments. In this thesis, we push the idea of caching at the edge a step further, and we propose to use public or private transportation as mobile small cells and caches. In fact, vehicles are widespread in modern cities, and the majority of them could be readily equipped with network connectivity and storage. The adoption of such a mobile cloud, which does not suffer from energy constraints (compared to user equipments), reduces installation and maintenance costs (compared to small cells). In our work, a user can opportunistically download chunks of a requested content from nearby vehicles, and be redirected to the cellular network after a deadline (imposed by the operator) or when her playout buffer empties. The main goal of the work is to suggest to an operator how to optimally replicate content to minimize the load on the core network. The main contributions are: (i) Modelling. We model the above scenario considering heterogeneous content size, generic mobility and a number of other system parameters. (ii) Optimization. We formulate some optimization problems to calculate allocation policies under different models and constraints. (iii) Performance analysis. We build a MATLAB simulator to validate the theoretical findings through real trace-based simulations. We show that, even with low technology penetration, the proposed caching policies are able to offload more than 50 percent of the mobile traffic demand
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Chen, Ruiwei. "Uncertainty quantification in the simulation of road traffic and associated atmospheric emissions in a metropolitan area." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1029/document.
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Ce travail porte sur la quantification d'incertitude dans la modélisation des émissions de polluants atmosphériques dues au trafic routier d'une aire urbaine. Une chaîne de modélisations des émissions de polluants atmosphériques est construite, en couplant un modèle d’affectation dynamique du trafic (ADT) avec un modèle de facteurs d’émission. Cette chaîne est appliquée à l’agglomération de Clermont-Ferrand (France) à la résolution de la rue. Un métamodèle de l’ADT est construit pour réduire le temps d’évaluation du modèle. Une analyse de sensibilité globale est ensuite effectuée sur cette chaîne, afin d’identifier les entrées les plus influentes sur les sorties. Enfin, pour la quantification d’incertitude, deux ensembles sont construits avec l’approche de Monte Carlo, l’un pour l’ADT et l’autre pour les émissions. L’ensemble d’ADT est évalué et amélioré grâce à la comparaison avec les débits du trafic observés, afin de mieux échantillonner les incertitudesThis work focuses on the uncertainty quantification in the modeling of road traffic emissions in a metropolitan area. The first step is to estimate the time-dependent traffic flow at street-resolution for a full agglomeration area, using a dynamic traffic assignment (DTA) model. Then, a metamodel is built for the DTA model set up for the agglomeration, in order to reduce the computational cost of the DTA simulation. Then the road traffic emissions of atmospheric pollutants are estimated at street resolution, based on a modeling chain that couples the DTA metamodel with an emission factor model. This modeling chain is then used to conduct a global sensitivity analysis to identify the most influential inputs in computed traffic flows, speeds and emissions. At last, the uncertainty quantification is carried out based on ensemble simulations using Monte Carlo approach. The ensemble is evaluated with observations in order to check and optimize its reliability
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Kehoe, Nicholas Paul. "An Analysis of Traffic Behavior at Freeway Diverge Sections using Traffic Microsimulation Software." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/76810.
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Microscopic simulation traffic models are widely used by transportation researchers and practitioners to evaluate and plan for transportation facilities. The intent of these models is to estimate the second-by-second vehicle movements and interactions on such facilities. Due to constraints related to time, budget, and availability of data, these models are typically designed in such a way where the microscopic output is viewed on the macroscopic level. Inherently, this can leave uncertainty to how the model estimates the individual interactions between vehicles on the microscopic level. This thesis utilizes three microsimulation models, INTEGRATION, VISSIM, and CORSIM, to investigate the lane changing behavior as vehicles approach a freeway diverge area. The count of lane changes, lane use distribution, and visual inspection of the simulated lane changing behavior was compared to video data collected at two freeway diverge areas on U.S. 460 in the vicinity of Blacksburg, Virginia during both off-peak and peak periods. It was observed that all three models generally overestimated the number of lane changes near the diverge areas compared to field observations. By modifying the models' lane changing logic, the models were able to closely match field observations in one of the four scenarios. It was found that microsimulation models accurately estimated the lane use distribution. In addition, the INTEGRATION lane use distribution results were found to be more consistent when compared to observed lane use distribution than either VISSIM or CORSIM.Master of Science
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Amanzholov, Anuar. "Analysis of off-peak traffic signal operations." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 129 p, 2008. http://proquest.umi.com/pqdweb?did=1605156311&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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François, Axel. "Interopérabilité des modèles géométriques pour les Systèmes d'Information Géographique : applications de la norme ISO 19107." Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX22078/document.
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Le contexte économique actuel montre que la représentation et l'analyse des données dans l'espace 3D croît de plus en plus dans les Systèmes d'Information Géographique (SIG). Le nombre d'applications SIG est en constante augmentation dans de nombreux secteurs d'activités comme par exemple la Défense, l'Aménagement du Territoire ou la Sécurité Civile. Cependant, nous voyons l'émergence d'une forte demande pour l'analyse 3D dans les SIG. Ces développements nécessitent une standardisation des structures de données et d'échanges. Cette démarche est réalisée par l'Open Geospatial Consortium (OGC) et l'organisation internationale de normalisation (ISO). Une norme récente (ISO 19107:2003) décrit les objets complexes à prendre en compte et les traitements qu’il est possible de leur appliquer. Elle cherche à mettre en place l’interopérabilité des échanges et des analyses de données géométriques et topologiques dans les SIG. Actuellement aucune implémentation informatique complète de cette norme n’a été encore réalisée, compte tenu de son niveau d'abstraction. Une version simplifiée a toutefois été développée pour des objets uniquement 2D (ISO 19137:2007). Ce travail de thèse propose la modélisation et l’analyse d'objets complexes dans un espace tridimensionnel, et les traitements associés pour réaliser une première bibliothèque de fonctionnalités conforme à la norme ISO 19107. De plus, cette norme est actuellement portée en révision au sein du consortium OGC (Open Geospatial Consortium, www.opengeospatial.org) avec une nécessité de correction et d’évolution. Les travaux menés jusqu'à présent ont permis d’apporter une contribution pertinente avec l'ajout de nouvelles primitives géométriques, l'harmonisation de primitives par l'usage de courbes et surfaces paramétriques rationnelles. Les travaux sur cette norme ont permis également l’élaboration d'une application au sein de la société GEOMATYS, rendant possible la modélisation et l'analyse 3D d'un trafic aérien reposant sur des données SIGIn the current economic context, the representation and the analysis of 3D data is growing more and more in the field of Geographic Information Systems (GIS). The number of GIS applications is constantly increasing in many industries, such as Defense, Regional Development and Civil Security. However, we can point out the emergence of an important request for 3D analysis in GIS. These developments require a standardization of data and exchange structures. This is carried out by Open Geospatial Consortium (OGC) and International Organization for Standardization (ISO). A recent standard (ISO 19107:2003) describes the complex objects to be taken into consideration and the associated treatments that can be used. It aims to develop interoperable exchange and analysis of geometric and topological data in GIS. Currently, no complete implementation on a computer of this standard has been done yet, regarding the level of abstraction sought. However, a simplified version was exclusively developed for 2D objects (ISO 19137:2007). This thesis proposes the modeling and the analysis of complex objects in three dimensional space, with their associated treatments. The objective is to create a first library whose the features are conform to ISO19107. Moreover, this standard is currently under review within the OGC Consortium (Open Geospatial Consortium) with a need for correction and evolution. The work done until now have enabled us to make a meaningful contribution with the addition of new geometrical primitives, the harmonization of primitives through the use of rational parametric curves and surfaces. The works on this standard also allowed the development of an application within the GEOMATYS company, making possible the 3D modeling and analysis for traffic simulation based on GIS data
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Watson, Christopher Earl. "Statistical analysis of crashes occurring at intersections in malfunction flash." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26508.
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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009.Committee Member: Hunter, Michael; Committee Member: Meyer, Michael; Committee Member: Rodgers, Michael. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Zhu, Ye. "On traffic analysis in anonymous communication networks." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1758.
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Palacín, Mateo Manuel. "The Internet ecosystem: a traffic measurement analysis." Doctoral thesis, Universitat Pompeu Fabra, 2015. http://hdl.handle.net/10803/326736.
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The analysis of the interconnection status-quo between content providers and Internet Service Providers (ISPs) is essential to understand the evolution of the Internet ecosystem. In the last years we have witnessed a spectacular increase of Internet traffic, especially multimedia content, which has driven both content providers and operators to rethink their interconnection models. This thesis performs an extensive traffic analysis from two perspectives to understand the rationale behind the Internet players. First, we analyse the traffic from the perspective of the evolution of the Internet protocols. Analyzing the protocols we pretend to observe whether the traffic pattern has changed while new applications have emerged and the demand have exploded. Second, we collect a dataset of Internet traces to evaluate the connectivity between access ISPs and the most popular content providers. Analyzing the Internet traces we want to identify the correlations in the interconnection models that different Internet players use.El análisis de las interconexiones entre proveedores de contenidos y operadores de Internet es esencial para entender la evolución del ecosistema de Internet. En los últimos años hemos sido testigos de un espectacular crecimiento del tráfico multimedia que ha llevado tanto a los proveedores de contenidos como a los operadores a replantearse sus modelos de interconexión. En esta tesis se realiza un análisis del tráfico de Internet des de dos perspectivas. Primero, se analiza el tráfico desde una perspectiva de los protocolos. Gracias al análisis de los protocolos se observa cómo ha cambiado el tráfico debido a la irrupción de nuevas aplicaciones y al incremento de la demanda de Internet. Segundo, se han realizado medidas que nos permite evaluar la conectividad entre diferentes operadores y proveedores de contenidos. El análisis de estos datos nos permite identificar correlaciones entre los diferentes modelos de interconexión que utilizan los operadores.
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Zhang, Yichi. "Residential Network Traffic and User Behavior Analysis." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-27001.
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Internet usage is changing and the demands on the broadband networks are ever increasing. So it is still crucial to understand today's network traffic and the usage patterns of the end users, which will lead to more efficient network design, energy and costs savings, and improvement of the service offered to end users. This thesis aims at finding hidden patterns of traffic and user behavior in a residential fiber based access network. To address the problem, a systematic framework of traffic measurement and analysis is developed. It involves PacketLogic traffic data collecting, MySQL database storing, and traffic and user behavior analysis by using Python scripts. Our approach provides new insights on residential network traffic properties and Internet user habits of households, covering topics of aggregated traffic pattern, household traffic modeling, traffic and user penetration for applications, grouping analysis by cluster and subscriber, and concurrent application analysis. The analysis solutions we provide are based on open source tools without proprietary, giving the most flexibility for codes modification and distribution.
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Naboulsi, Diala. "Analysis and exploitation of mobile traffic datasets." Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0084/document.
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Les équipements mobiles deviennent une partie intégrale de notre vie numérique. Ces équipements interagissent avec l'infrastructure des réseaux cellulaires et leur activité est enregistrée pour des buts de facturation et monitoring sous forme de données de trafic mobile. Les travaux menés dans cette thèse se focalisent sur le potentiel que portent ces données pour l'amélioration des réseaux cellulaires futurs. D'une part, on montre que les données mobiles permettent de construire des profils spatio-temporels typiques de l'utilisation des réseaux cellulaires en environnement urbain. Cette analyse permet aussi la détection des comportements atypiques dans le réseau qui sont liés à des événements spéciaux. D'autre part, on montre que les données mobiles constituent un élément méthodologique important pour l'évaluation des solutions réseaux. Dans ce sens, on propose un mécanisme pour réduire la consommation énergétique des infrastructures cellulaires, en contrôlant la puissance sur le réseau d'accès à différents moments de la journée, tout en assurant la couverture géographique du réseau. On exploite aussi ces données pour évaluer les gains apportés par une nouvelle architecture de réseau d'accès, basée sur la virtualisation d'une partie du réseau et sa centralisation dans un cloud. Nos résultats montrent que cette architecture est bénéfique du point de vue des messages de signalisation, notamment pour les utilisateurs mobilesMobile devices are becoming an integral part of our everyday digitalized life. In 2014, the number of mobile devices, connected to the internet and consuming traffic, has even exceeded the number of human beings on earth. These devices constantly interact with the network infrastructure and their activity is recorded by network operators, for monitoring and billing purposes. The resulting logs, collected as mobile traffic datasets, convey important information concerning spatio-temporal traffic dynamics, relating to large populations with millions of individuals. The thesis sheds light on the potential carried by mobile traffic datasets for future cellular networks. On one hand, we target the analysis of these datasets. We propose a usage patterns characterization framework, capable of defining meaningful categories of mobile traffic profiles and classifying network usages accordingly. On the other hand, we exploit mobile traffic datasets to evaluate two dynamic networking solutions. First, we focus on the reduction of energy consumption over typical Radio Access Networks (RAN). We introduce a power control mechanism that adapts the RAN's power configuration to users demands, while maintaining a geographical coverage. We show that our scheme allows to significantly reduce power consumption over the network infrastructure. Second, we study the problem of topology management of future Cloud-RAN (C-RAN). We propose a mobility-driven dynamic association scheme of the C-RAN components, which takes into account users traffic demand. The introduced strategy is observed to lead to important savings in the network, in terms of handovers
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Zhou, Xinan. "Cellular data traffic, analysis, models, and scenarios." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0020/MQ57756.pdf.
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Washington, Alicia Nicki. "Performance Analysis of Traffic-Groomed Optical Networks." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-03242005-005650/.
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Wavelength division multiplexing (WDM) has emerged as a viable solution to the increasing bandwidth demands of current backbone networks. Traffic grooming allows the resources available on a single wavelength to be utilized by multiple traffic streams. These networks will support large amounts of traffic from various sources. In view of this, our research focuses on the analysis of such types of networks, and in particular on a traffic-groomed tandem optical network that supports multiple sources each with unique resource requirements. We developed a decomposition algorithm for the analysis of this network using a modified version of Courtois? method. This work was extended to analyze tandem networks with a large number of wavelengths and resources per wavelength using a modified version of the recursion developed by Nilsson et. al. Finally, we extended our work to a traffic-groomed tandem optical network employing alternate routing and supporting traffic from multiple sources. For each method, numerical results show that, overall, our approximation provides good accuracy.
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Weijermars, Wilhelmina Adriana Maria. "Analysis of urban traffic patterns using clustering." Enschede : University of Twente [Host], 2007. http://doc.utwente.nl/57837.
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Rehm, Frank. "Visual data analysis in air traffic management /." Köln : DLR, 2007. http://diglib.uni-magdeburg.de/Dissertationen/2007/frarehm.htm.
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Nolan, Le E. "Transport Traffic Analysis for Abusive Infrastructure Characterization." Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/17429.
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Approved for public release; distribution is unlimitedThis thesis investigates a novel approach to identifying discriminating features of communications involving abusive hosts. The technique uses per-packet TCP header and timing features to identify congestion, flow-control, and other low-level network and system characteristics. These characteristics are inherent to the poorly connected, under-provisioned, low-end, and overloaded hosts or links typical of abusive infrastructure making them difficult for an adversary to manipulate. Supervised classifiers use these features to infer likely abusive network hosts. Prior work investigates such features to opportunistically identify inbound abusive traffic, this thesis seeks to perform active probing to generally characterize abusive infrastructure. Our approach is IP address and content agnostic, and therefore privacy-preserving to permit wider deployment than known-abusive web sites, we achieve a classification accuracy of 94 percent with a 3 percent false positive rate using only transport features. Our results suggest that transport traffic analysis can block and identify, in real-time, abusive hosts unknown to blocklists, and provide a difficult-to-subvert addition to existing schemes.
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Thomson, Malcolm S. "Real-time image processing for traffic analysis." Thesis, Edinburgh Napier University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260986.
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Atiquzzaman, M. "Algorithms and architectures for automatic traffic analysis." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378141.
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Kreibich, Christian Peter. "Structural traffic analysis for network security monitoring." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613090.
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Pego, Maeletso. "Analysis of traffic accidents in Gaborone, Botswana." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2395.
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Thesis (MSc (Geography and Environmental Studies))--University of Stellenbosch, 2009.Botswana, a developing country in southern Africa, has not been spared the proliferating scourge of traffic accidents that is sweeping across the world. After HIV/AIDS, traffic accidents are the second largest cause of unnatural deaths in Botswana. The country is losing two per cent of its GDP every year to traffic accident costs. Furthermore, road safety is one of the major challenges the country will have to overcome in order to achieve its Vision 2016. This study investigates traffic accidents in Gaborone, the capital city of Botswana, for the years 2000 and 2005. The study analyses the characteristics of traffic accidents, examines their causes, maps the spatial distribution of traffic accidents for 2000 and 2005, and outlines the countermeasures government is instituting to curb accidents. The main data on traffic accidents used was extracted from the microcomputer accidents analysis package V5.0 (MAAP 5) obtained from the Traffic Police Division. Semi-structured interviews with transport and safety officers, traffic police and other stakeholders were conducted. The interviews were mainly about what government is doing to reduce the carnage caused by traffic accidents. Existing reports were also used as data sources. Microsoft Excel and ArcGIS 9.1 packages were used to do the analyses. The road casualties of drivers/riders are concentrated in the economically active age category of 15-64 years (95% for all casualties). In particular, the casualties are very high in the 20-39 age cohort with one third and three quarters of all casualties for 2000 and 2005 respectively. In addition, driver casualties by gender for the 20-39 age cohort show a high representation of males, namely 57% and 64% for 2000 and 2005 respectively.
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Madden, Joshua. "A statistical analysis of high-traffic websites." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/17650.
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Master of ScienceDepartment of Journalism and Mass Communications
Steven Smethers
Although scholars have increasingly recognized the important role of the Internet within the field of mass communications, little research has been done analyzing the behavior of individuals online. The success or failure of a site is often dependent on the number of visitors it receives (often called “traffic”) and this includes newspapers that are attempting to direct larger audiences to their websites. Theoretical arguments have been made for certain factors (region, social media presence, backlinks, etc.) having a positive correlation with traffic, but few, if any, statistical analyses have been done on traffic patterns. This study looks at a sample of approximately 300 high-traffic websites and forms several regression models in order to analyze which factors are most highly correlated with Internet traffic and what the nature of that correlation is.
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Eucker, William. "A geospatial analysis of Arctic marine traffic." Thesis, University of Cambridge, 2012. https://www.repository.cam.ac.uk/handle/1810/248854.
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Recent changes in Arctic Ocean climate dynamics and marine activity in the region require re-evaluation of physical operating conditions, ship traffic patterns, and policy requirements. This study used (1) government surveys, (2) vessel reports, and (3) Automatic Identification System (AIS) messages to characterize the spatial and temporal variability of surface vessel traffic in relation to various sea-ice conditions on the Arctic Ocean during a year-long study from 1 April 2010 to 31 March 2011. Data sources, methods of analysis, and errors were discussed. Three principal topics were examined. First, sea-ice cover on the Arctic Ocean was analysed to determine the physical access for marine operations. Daily sea-ice concentration data based on satellite passive microwave measurements were used to calculate the extent of open water and duration of the sea-ice season. Second, ship traffic on the Arctic Ocean was analysed to determine the present patterns of human activity. Time-stamped AIS messages encoded with Global Navigation Satellite System (GNSS) positions received by a commercial satellite constellation from north of the Arctic Circle (66·56°N) were used to calculate the distribution of vessels per unit area. Satellite AIS data from SpaceQuest, Limited, were compared with land-based vessel observations during the study period from the Marine Exchange of Alaska and the Port of Longyearbyen. Third, the spatial and temporal relationship between sea ice and surface vessels on the Arctic Ocean was analysed to determine potential policy implications. Three groups of marine operations with distinct characteristics were determined from the analysis: operations in perennial open water, operations in the seasonal ice zone, and operations in the perennial ice zone. Throughout the study year, most ships north of 66·56°N operated in perennially icefree areas, but year-round operations also occurred in ice-covered areas. The results from this study identify new pathways of information to enable consistent pan-Arctic assessment of physical operating conditions and ship traffic patterns. This approach provides novel considerations to sustainably develop a safe, secure, and environmentally protected Arctic Ocean.