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My Habilitation
A habilitation is like a PhD after a PhD.
"Habilitation is the highest academic qualification a scholar can achieve by his or her own pursuit in several European and Asian countries. Earned after obtaining a research doctorate, such as a PhD, habilitation requires the candidate to write a professorial thesis (often known as a Habilitationsschrift, or Habilitation treatise) based on independent scholarship, reviewed by and defended before an academic committee in a process similar to that for the doctoral dissertation. However, the level of scholarship has to be considerably higher than that required for a research doctoral (PhD) thesis in terms of quality and quantity, and must be accomplished independently, in contrast with a PhD dissertation typically directed or guided by a faculty supervisor."
Source: Wikipedia
More details can be found in Wikipedia. The full habilitation procedure at the University of Duisburg-Essen is defined in the corresponding Habilitationsordnung (in German language).
The complete BibTeX references in a single file can be found here!
Dreibholz, Thomas: ``Evaluation and Optimisation of Multi-Path Transport using the Stream Control Transmission Protocol´´ (PDF, 36779 KiB, 🇬🇧), Habilitation Treatise, University of Duisburg-Essen, Faculty of Economics, Institute for Computer Science and Business Information Systems, URN urn:nbn:de:hbz:464-20120315-103208-1, March 13, 2012, [BibTeX, XML].
Keywords: Stream Control Transmission Protocol (SCTP), Multi-Path Transport, Dissimilar Paths, Fairness, Evaluation, Optimisation
Abstract: The Stream Control Transmission Protocol (SCTP) as defined in RFC 4960 is an advanced Transport Layer protocol that provides support for multi-homing. That is, SCTP endpoints may simultaneously use multiple Network Layer addresses, which allows to connect the endpoints to multiple networks for redundancy purposes. However, for the transfer of user data, only one of the possible paths is currently used at a time. All other paths remain as backup and are only used for retransmissions. Clearly, the existence of multiple paths has led to the idea of applying load sharing among the paths. An extension to SCTP – denoted as Concurrent Multipath Transfer (CMT) – realises this load sharing functionality. While this approach works well for similar paths, i.e. paths having similar characteristics regarding bandwidths, bit error rates and delays, the use of dissimilar paths does not work that neatly. In this thesis, the issues of dissimilar paths for CMT-based load sharing will be demonstrated first. The reasons for these issues will be identified and solutions proposed. These solutions will be evaluated in simulations, as well as partially also in a real-world Internet testbed setup, in order to show their effectiveness. In particular, it will be shown that a combination of multiple mechanisms is necessary to make CMT work as expected under a wide range of network and system parameters. Furthermore, the fairness of CMT-based transport – in concurrency to classic non-CMT flows – will be analysed. The usage of plain CMT leads to an overly aggressive bandwidth occupation on so-called shared bottlenecks. As a countermeasure, the idea of Resource Pooling will be utilised. For this purpose, two new and one adapted congestion control approach – all based on the Resource Pooling principle – will be introduced and examined in similar as well as dissimilar path setups, in order to show how to fairly deploy CMT transport in the Internet. The results of this work have also been contributed to the ongoing IETF standardisation process of SCTP and its extensions.
MD5: add34f0b780cb35b7ee1f963ea85e59c
Dreibholz, Thomas: ``Konzepte für das Future Internet aus der Netzperspektive´´ (PDF, 5777 KiB, 🇩🇪), Habilitation Talk, University of Duisburg-Essen, Faculty of Economics, Institute for Computer Science and Business Information Systems, URN urn:nbn:de:hbz:464-20120404-135350-0, March 13, 2012, [BibTeX, XML].
Keywords: Future Internet, Habilitationsvortrag
Abstract: Vielen seiner Benutzer erscheint das Internet als neuartig und hochmodern. Seine Grundlagen jedoch sind keineswegs neu, sondern basieren auf mittlerweile fast 40 Jahre alten Ideen. Dienste werden mittels eines geschichteten, hierarchischen Protokollstacks realisiert, bei welchem eine Interaktion nicht-benachbarter Schichten nicht vorgesehen ist. Dieser starre Aufbau macht bereits das Anpassen der Internet-Architektur an die Anforderungen der heutigen Anwendungen – wie etwa File Sharing, Videotelefonie und mobile Endgeräte – kompliziert. Die großen Herausforderungen des zukünftigen Internets – welches als das Future Internet bezeichnet wird – mit Anwendungsszenarien wie Cloud Computing, Internet of Things, Sensornetzwerken und vielen weiteren – erfordern jedoch noch weitaus umfangreichere Anpassungen. Zudem ist eine große Flexibilität erforderlich, um auch weiteren – heute noch nicht absehbaren – Anforderungen gerecht zu werden. Im Rahmen dieses Habilitationsvortrages wird zunächst kurz auf die Probleme des aktuellen Internets eingegangen sowie die Herausforderungen des Future Internets vorgestellt. Im Anschluss daran wird eine Auswahl der für den Übergang zum Future Internet möglichen evolutionären sowie revolutionären Ansätze vorgestellt. Der Schwerpunkt liegt hierbei auf den noch relativ neuen – und in der Forschung momentan sehr aktiv diskutierten – revolutionären Ansätzen, welche mit der Idee des sogenannten Clean Slate einen vollständigen Neuansatz anstreben. Hierbei werden die Ansätze der Funktionalen Komposition, des Content-Centric Networking sowie der Virtualisierung von Netzwerken vorgestellt. Zum Schluss wird dann auf die Frage eingegangen, wie eine Nutzung der vorgestellten Ansätze in der Praxis möglich ist und welche der aktuell in Diskussion befindlichen Ansätze sich in Zukunft voraussichtlich durchsetzen werden.
MD5: bd09fd9172fccb9edd4ee88299038f47
©️ 18.11.2024 Thomas Dreibholz, Simula Research Laboratory / Center for Resilient Networks and Applications / NorNet
