Progressive introduction of network softwarization in operational telecom networks: advances at architectural, service and transport levels

Technological paradigms such as Software Defined Networking, Network Function Virtualization and Network Slicing are altogether offering new ways of providing services. This process is widely known as Network Softwarization, where traditional operational networks adopt capabilities and mechanisms inherit form the computing world, such as programmability, virtualization and multi-tenancy. This adoption brings a number of challenges, both from the technological and operational perspectives. On the other hand, they provide an unprecedented flexibility opening opportunities to developing new services and new ways of exploiting and consuming telecom networks. This Thesis first overviews the implications of the progressive introduction of network softwarization in operational networks for later on detail some advances at different levels, namely architectural, service and transport levels. It is done through specific exemplary use cases and evolution scenarios, with the goal of illustrating both new possibilities and existing gaps for the ongoing transition towards an advanced future mode of operation. This is performed from the perspective of a telecom operator, paying special attention on how to integrate all these paradigms into operational networks for assisting on their evolution targeting new, more sophisticated service demands.Programa de Doctorado en Ingeniería Telemática por la Universidad Carlos III de MadridPresidente: Eduardo Juan Jacob Taquet.- Secretario: Francisco Valera Pintor.- Vocal: Jorge López Vizcaín

Software asset management processes and model

The industry must now focus on software assets in order to improve the management of purchased software and their associated licenses: over the years, organizations have indeed purchased a significant amount of commercial software and they now have to manage their related costs while ensuring that the license's terms and conditions are respected. Until now, the industry has been offering incomplete solutions to the management of software assets while using different approaches, terminologies and tools with varying functional scopes. The industry recognizes the need to improve Software Asset Management (SAM) but does not agree on the means to do so. This thesis proposes to start with a common industry SAM definition. To help organizations use the processes that constitute the SAM definition, a descriptive analysis of the processes, an assessment method and a graphical representation are provided to facilitate its use in the industry. Furthermore, to ensure the set of processes reflect the view and needs of the industry; the author actively participated in the writing of the ISO standard on SAM: the panel of experts contributing to ISO also provided a mean to validate several of the SAM topics discussed in this thesis. The research objectives are to: 1. Actively contribute to the development and to the content of the ISO international standard on SAM (ISO/IEC 19770-1). 2. Capture, idenfify and analyze elements that are relevant to SAM, including those that would not make it into the final version of the international standard. 3. Provide an analysis of the international SAM standard with respect to the 27 processes within ISO/IEC 19770-1. 4. Develop an exploratory assessment method to allow organizations to determine their gaps against ISO/IEC 19770-1. The approach selected was to align the research work of this thesis with the then new ISO working group created in 2002 to address issues related to the management of software assets and to contribute actively to the development of an international standard on SAM processes, that is: ISO/IEC 19770-1. The results of this thesis are: 1. A common set of processes to describe the scope and content of SAM. This allows the industry to have a common point of reference and vocabulary when referring to SAM. 2. Through a literature review covering both the industry and the research community it was possible to highlights the divergence of scope and terminology with software manufacturer and the lack of agreement of what is a SAM manager. This thesis addresses these issues by identifying the full set of SAM processes. 3. The thesis analyses the standard used as the basis of reference for the assessment, that is: the ISO/IEC 19770-1 standard on SAM. The description and analysis of this standard allows for a better understanding of the purpose of each process and the interactions across existing standards such as ISO/IEC 20000 on Service Management. 4. The thesis also proposes a method to assess and assign a maturity level to each of the processes of the ISO/IEC 19770-1 standard; the ISO/IEC 15504 standard is used to perform the assessment. 5. Organizations recognize that poor management of software assets puts the organization at risk. However, organizations did not have any common way of assessing these risks. With the use of the ISO/IEC 19770-1 standard and the assessment method, organization can now identify the maturity levels of control points and assess their impact on the organization

Ingénierie de modèle pour la sécurité des systèmes critiques ferroviaires

Development and application of formal languages are a long-standing challenge within the computer science domain. One particular challenge is the acceptance of industry. This thesis presents some model-based methodologies for modelling and verification of the French railway interlocking systems (RIS). The first issue is the modellization of interlocking system by coloured Petri nets (CPNs). A generic and compact modelling framework is introduced, in which the interlocking rules are modelled in a hierarchical structure while the railway layout is modelled in a geographical perspective. Then, a modelling pattern is presented, which is a parameterized model respecting the French national rules. It is a reusable solution that can be applied in different stations. Then, an event-based concept is brought into the modelling process of low-level part of RIS to better describe internal interactions of relay-based logic. The second issue is the transformation of coloured Petri nets into B machines, which can help designers on the way from analysis to implementation. Firstly, a detailed mapping methodology from non-hierarchical CPNs to abstract B machine notations is presented. Then the hierarchy and the transition priority of CPNs are successively integrated into the mapping process, in order to enrich the adaptability of the transformation. This transformation is compatible with various types of colour sets and the transformed B machines can be automatically proved by Atelier B. All these works at different levels contribute towards a global safe analysis frameworkLe développement et l’application des langages formels sont un défi à long terme pour la science informatique. Un enjeu particulier est l’acceptation par l’industrie. Cette thèse présente une approche pour la modélisation et la vérification des postes d’aiguillage français. La première question est la modélisation du système d’enclenchement par les réseaux de Petri colorés (RdPC). Un cadre de modélisation générique et compact est introduit, dans lequel les règles d’enclenchement sont modélisées dans une structure hiérarchique, tandis que les installations sont modélisées dans une perspective géographique. Ensuite, un patron de modèle est présenté. C’est un modèle paramétré qui intègre les règles nationales françaises qui peut être appliquée pour différentes gares. Puis, un concept basé sur l’événement est présenté dans le processus de modélisation des parties basses des postes d’aiguillage. La deuxième question est la transformation des RdPCs en machines B, qui va aider les concepteurs sur la route de l’analyse à application. Tout d’abord, une méthodologie détaillée, s’appuyant sur une table de correspondance, du RdPCs non-hiérarchiques vers les notations B est présentée. Ensuite, la hiérarchie et la priorité des transitions du RdPC sont successivement intégrées dans le processus de mapping, afin d’enrichir les possibilités de types de modèles en entrées de la transformation. Les machines B produites par la transformation permettent la preuve automatique intégrale par l’Atelier B. L’ensemble de ces travaux, chacun à leur niveau, contribuent à renforcer l’efficacité d’un cadre global d’analyse sécuritair