<p>With Cloud Computing becoming a popular term on the Information Technology (IT) market, security and accountability has become important issues to highlight. In our research we review these concepts by focusing on security risks with Cloud Computing and the associated services; Software, Platform and Infrastructure (SPI) and connecting them with a social study of trust.</p><p>The method that was conducted during our research was reviewing secondary literature, interviewing different experts regarding Cloud Computing and relating standards already established by ENISA, NIST, and CSA to the interviews.</p><p>The result of this study shows connections between the specific SPIs, both how they compare, but also how they differ. In the end we were also able to rank the top security risks from interviews with experts and see which SPI could be the most insecure one and  what countermeasures could be applied.</p><p>This was further related to trust and Service Level Agreement (SLA) in Cloud Computing to show how the security risks we discuss are related to these two specific areas. By highlighting this we wanted to present useable information for both clients and providers in how to create a better Cloud Computing environment.</p>

Αντικείμενο της παρούσας Διατριβής είναι η μελέτη της απόδοσης και η εισαγωγή νέων χαρακτηριστικών σε μοντέλα για την παροχή υπηρεσιών με εγγυήσεις ποιότητας στα σύγχρονα IP δίκτυα καθώς και η εισαγωγή των απαραίτητων επιχειρησιακών λειτουργιών για την εφαρμογή των μοντέλων αυτών, με στόχο τη βελτίωση της απόδοσης. Ακολουθώντας μια καταγραφή και αξιολόγηση των μηχανισμών και αρχιτεκτονικών που εισάγουν τη διαφοροποίηση εξυπηρέτησης στα IP δίκτυα, η μελέτη που παρουσιάζεται εδώ ακολουθεί σε όλα της τα στάδια τις αρχές της αρχιτεκτονικής DiffServ, η οποία επιτρέπει την παροχή ενός συγκεκριμένου εύρους υπηρεσιών με εγγυήσεις ποιότητας σε συναθροίσεις ροών και περιορίζει την πολυπλοκότητα στα όρια του δικτύου. Η απόδοση και η αποτελεσματικότητα των μηχανισμών και λειτουργιών διαφοροποίησης εξυπηρέτησης με βάση την αρχιτεκτονική DiffServ αξιολογούνται με βάση την εξασφάλιση εγγυημένης χωρητικότητας, φραγμένης από-άκρο-σε-άκρο καθυστέρησης, ελαχιστοποιημένων απωλειών πακέτων και φραγμένου jitter. Ωστόσο, σε κάθε μοντέλο υπηρεσίας για την παροχή QoS, τονίζεται η σημασία της εξασφάλισης των καλύτερων δυνατών εγγυήσεων ποιότητας με την ελάχιστη δυνατή πολυπλοκότητα. Τα διαφορετικά μοντέλα υπηρεσιών θέτουν συγκεκριμένους στόχους λαμβάνοντας υπόψη τις ανάγκες των εφαρμογών στις οποίες απευθύνονται. Οι δύο επικρατέστερες κατηγορίες υπηρεσιών στα πλαίσια της αρχιτεκτονικής DiffServ είναι η κατηγορία των υπηρεσιών μέγιστης προτεραιότητας και η κατηγορία των υπηρεσιών εγγυημένης χωρητικότητας σε συνθήκες συμφόρησης. Στην πρώτη κατηγορία, προτείνεται το μοντέλο υπηρεσίας Gold, το οποίο ακολουθεί τις αρχές τις αρχιτεκτονικής DiffServ για να παρέχει βέλτιστη ποιότητα εξυπηρέτησης σε συναθροίσεις IP ροών, ενώ ταυτόχρονα μπορεί να εφαρμοστεί πρακτικά σε δίκτυα παραγωγής. Στη δεύτερη κατηγορία, προτείνεται το μοντέλο υπηρεσίας Relative για την παροχή υπηρεσιών εγγυημένης χωρητικότητας σε συνθήκες συμφόρησης, με βασικά χαρακτηριστικά την μείωση της υπολογιστικής πολυπλοκότητας και την βελτίωση της δικαιοσύνης μεταξύ των εξυπηρετούμενων TCP ροών. Η υπηρεσία Gold διατηρεί την αρχή της επεκτασιμότητας και παρέχει αυστηρές εγγυήσεις ποιότητας αλλά ταυτόχρονα επιτρέπει την εφαρμογή μηχανισμού ελέγχου αποδοχής νέων αιτημάτων χωρίς διακοπή της λειτουργίας του δικτύου. Eισάγει επίσης ένα νέο χαρακτηριστικό σε σχέση με τα υπάρχοντα σχήματα: την διαφοροποίηση ως προς την εγγυημένη μέγιστη καθυστέρηση που παρέχεται στις ροές. Υλοποιείται με τη χρονοδρομολόγηση LA-EDF, που εισάγει την έννοια της διαφοροποιημένης εξυπηρέτησης εντός της ίδιας κλάσης υπηρεσίας και λειτουργεί ως υποστηρικτικός μηχανισμός του ελέγχου αποδοχής κλήσεων, τον αλγόριθμο DBAC για την αποδοχή κλήσεων χωρίς επέμβαση στη λειτουργία του δικτύου και την δρομολόγηση εξισορρόπησης φόρτου για την καλύτερη αξιοποίηση των διαθέσιμων πόρων χωρίς να παραβιάζονται οι εγγυήσεις ποιότητας. Η υπηρεσία Relative επιτυγχάνει προσαρμοστικότητα σε συνθήκες μεταβαλλόμενου φόρτου, δίκαιη διαφοροποίηση, υψηλή απόδοση, αύξηση της χρησιμοποίησης των διαθέσιμων πόρων ενώ αντιμετωπίζει πολλές από τις αδυναμίες που παρουσιάζουν αντίστοιχα μοντέλα. Υλοποιείται με τον μηχανισμό μαρκαρίσματος TWAM ο οποίος εφαρμόζεται στο σημείο εισόδου των ροών στο δίκτυο και αντιμετωπίζει τα θέματα της μη δίκαιης μεταχείρισης TCP ροών με τη μικρότερη δυνατή υπολογιστική επιβάρυνση σε σχέση με υπάρχοντες μηχανισμούς μαρκαρίσματος και τον μηχανισμό DWRED για την ενεργητική διαχείριση του αποθηκευτικού χώρου των ουρών, ο οποίος λειτουργεί με βάση το μαρκάρισμα της κίνησης που επιφέρει ο TWAM και προσαρμόζεται στις μεταβαλλόμενες συνθήκες λειτουργίας. Μεταξύ των καθοριστικών παραγόντων για την ευρεία υιοθέτηση υπηρεσιών βασισμένων στην αρχιτεκτονική DiffServ στα σύγχρονα δίκτυα παραγωγής, αναδεικνύονται η εισαγωγή ευέλικτων επιχειρηματικών μοντέλων για την υλοποίηση των υπηρεσιών αυτών στο εσωτερικό ενός δικτύου καθώς και χρέωσης των παρεχόμενων υπηρεσιών. Ο ορισμός Συμβολαίων Εξασφάλισης Επιπέδου Υπηρεσιών (ΣΕΕΥ) για δίκτυα που υποστηρίζουν την παροχή QoS υπηρεσιών με βάση την αρχιτεκτονική DiffServ έχει ως στόχο την εξασφάλιση της συμβατότητας των παρεχόμενων από διαφορετικά διασυνδεδεμένα δίκτυα υπηρεσιών προκειμένου για την από-άκρο-σε-άκρο εξασφάλιση εγγυήσεων ποιότητας. Προτείνεται ένα πρότυπο για την υλοποίηση διμερών ΣΕΕΥ σε IP δίκτυα που παρέχουν υπηρεσίες μέγιστης προτεραιότητας καθώς και μια μεθοδολογία για την υλοποίηση από-άκρο-σε-άκρο Συμβολαίων πάνω από διασυνδεδεμένα δίκτυα. Σε ένα IP δίκτυο, η εισαγωγή ενός αριθμού κλάσεων υπηρεσιών που διαφοροποιούνται στις παρεχόμενες ποιοτικές εγγυήσεις απαιτεί την εισαγωγή διαφοροποιημένων μοντέλων χρέωσης που επιπρόσθετα οδηγούν τους χρήστες στην επιλογή της κατάλληλης κλάσης υπηρεσίας η οποία μεγιστοποιεί την αντιληπτή χρησιμότητα. Προκειμένου για τη χρέωση υπηρεσιών με βάση την αρχιτεκτονική DiffServ, τα προφίλ κίνησης των χρηστών και οι διαφορές στην αντιληπτή ποιότητα αντιπροσωπεύουν τη χρησιμότητα που αντιλαμβάνεται ο χρήστης. Προτείνεται ένα μοντέλο χρέωσης όπου το προφίλ της κίνησης αποτελεί το αντικείμενο διαπραγμάτευσης του χρήστη με τον πάροχο, αφού ο χρήστης συνυπολογίσει τις εγγυήσεις ποιότητας εξυπηρέτησης που ανακοινώνονται από τον τελευταίο προκαταβολικά. Η καινοτομία του προτεινόμενου μοντέλου συνίσταται στις εξωτερικές συνθήκες (externalities) που υπεισέρχονται στα υφιστάμενα κόστη και προκαλούνται από τη φύση των υπηρεσιών που υλοποιούνται με βάση το μοντέλο DiffServ, καθώς επίσης και στον καθορισμό των πραγματικών τιμών με βάση τις οποίες χρεώνονται οι χρήστες. / The goal of this Dissertation is to study the performance of existing tools and the introduction of new features to quality of service provisioning models in IP networks as well as the introduction of the business models required for applying these models in an operational environment in ways that the performance is improved. Following the evaluation of mechanisms and architectures for differentiation of service in IP networks, the principles of the DiffServ framework have been adopted. The DiffServ framework specifies the provision of a set of services with qualitative guarantees to traffic aggregates, while keeping complexity at the network edges. The performance and effectiveness of service differentiation mechanisms according to the principles of the DiffServ framework are evaluated according to the following metrics: guaranteed capacity, bounded end-to-end delay, minimization of packet losses and jitter. However, in any QoS model, it is important to ensure the best quality possible by keeping complexity low. Each QoS model is designed to meet the needs of a different traffic type. The two prevailing service models within the DiffServ framework are the maximum priority, maximum quality model and the guaranteed capacity under congestion model. The proposed Gold service falls within the first category above, offering advanced quality to IP traffic aggregates with a set of principles that can easily be applied to operational networks. The proposed Relative service model provides guaranteed capacity under congestion by reducing the complexity and improving fairness among TCP flows. The Gold service preserves scalability and provides strict quality guarantees, incorporating a call admission control mechanism that operates without interfering with the network operations. It introduces a novel feature: differentiation of the guarantees on end-to-end delay provided to traffic flow. It is implemented using LA-EDF scheduling that introduces service differentiation within the same class and supports the call admission control functions, the DBAC algorithm for admission control and flow routing with load balancing for optimizing the use of available resources without compromising in terms of the guaranteed quality. The Relative service achieves high adaptability in transient load conditions, fair differentiation, high quality, increase in the utilization of available resources without demonstrating the same weaknesses as equivalent service models. It is implemented using the TWAM marking mechanism, which is applied at the network ingress and ensures fairness with less overhead than similar mechanisms, and DWRED, the active queue management mechanism that depends upon the TWAM marking and adapts to the varying load levels. The introduction of effective business and pricing models is crucial for the adoption of qualitative service models based on the DiffServ framework in a production network. The definition of Service Level Agreements (SLAs) for networks that provide QoS according to the principles of the DiffServ framework aims at introducing compatibility among the services provided for the provisioning of end-to-end quality guarantees. A template for the implementation for bilateral SLAs between networks that support the maximum priority, maximum quality service model is proposed, together with a methodology for implementing, based on the bilateral SLA, an end-to-end SLA over multiple domains. In an IP network, the introduction of a set of services classes with differing quality guarantees necessitates the application of differentiated pricing models that lead the users to the selection of the appropriate service class in order to maximize their perceived utility. Based on the principles of the DiffServ framework, the utility for each user is determined by the profile of his traffic and the quality of service he perceives. The proposed pricing model appoints the traffic profile as the parameter for negotiation between the user and the provider, after the user assesses the quality guarantees announced by the provider prior to the service provisioning. The innovation here lies in the introduction of externalities to the costs induced as well as the announcement of the actual prices upon which the user will eventually be charged. The externalities are imposed by the nature of the service models implemented according to the DiffServ framework.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

The emergence of new architectures like the cloud open new challenges for data management. It is no longer pertinent to reason with respect a to set of computing, storage and memory resources, instead it is necessary to conceive algorithms and processes considering an unlimited set of resources usable via a "pay as U go model", energy consumption or services reputation and provenance models. Instead of designing processes and algorithms considering as threshold the resources availability, the cloud imposes to take into consideration the economic cost of the processes vs. resources use, results presentation through access subscription, and the parallel exploitation of available resources. Our research contributes to the construction of service based data management systems. The objective is to design data management services guided by SLA contracts. We proposed methodologies, algorithms and tools for querying, deploying and executing service coordinations for programming data management functions. These functions, must respect QoS properties (security, reliability, fault tolerance, dynamic evolution and adaptability) and behaviour properties (e.g., transactional execution) adapted to application requirements. Our work proposes models and mechanisms for adding these properties to new service based data management functions.

Material supply systems have for a long time been regarded as an important function with strong potential to increase the performance of companies in different industries. Consequently, substantial research has been conducted in the field. However, in the pharmaceutical industry within research and development plants, material supply systems have historically not been a prioritized function. Therefore, there is a research gap regarding material supply systems in that peculiar context. This study aims to fill that gap by investigating how a material supply system could be designed and which factors are critical to achieve a cost-efficient service level within a research and development plant in the pharmaceutical industry. To do so, a single case study has been conducted at a Swedish pharmaceutical company’s research and development plant. An abductive approach has been applied to both test if the general design principles developed in other industries and business functions can be applied to this context. Further, context specific factors affecting the material supply system design needed to be identified and investigated to adapt the general design principles to the specific context by generalizing data. The empirical data was collected by utilizing focus groups, interviews, observations and documents. The findings yielded that there is a substantial potential for improvement of material supply systems within the context of this study. The existing decentralized inventory structure at the case company was a particularly vital aspect that hindered the system from operating cost-efficiently in relation to the service level and a centralization is crucial to improve. Further, calibration and a general decrease of safety stocks, order points and order quantities is essential to uphold a consistent service level at a justifiable cost at the case company. The general design principles and formulas retrieved from the theoretical framework was partly applicable in the context of this study but needed some adjustments. Especially the low volume articles with high variety in consumption rate was not suitable to be managed by the existing methods and needed another approach. Further, the context establishes high requirements on system dynamics, it comes with boundaries due to laws regulating the industry, and companies in the context generally need to be better at aligning their design factors to the purpose. The result of this study adds valuable content to the research field and fills the gap for material supply systems in the context of research and development plants in the pharmaceutical industry. Further studies are needed in this field to investigate how articles with low and varying demands can be managed within material supply systems cost-efficiently and with high service levels.

O objetivo deste estudo é realizar a avaliação da estrutura de três instituições públicas com relação às propostas de inovação organizacional por meio das mudanças em seus processos de trabalho. Este estudo abrange os contratos terceirizados realizados por meio de processo licitatório com a utilização de Acordo de Nível de Serviço (ANS), que possui critérios objetivos de mensuração dos resultados contratados. Isso permite adequar o pagamento das faturas dos contratos de acordo com a quantidade e qualidade dos serviços prestados, constituindo o processo inovativo a ser estudado neste trabalho. Para isso, foram realizadas entrevistas com servidores das áreas que atuam desde o planejamento até o acompanhamento e execução dos contratos terceirizados continuados de forma a verificar a percepção com relação à inovação em sua instituição, cultura organizacional e apoio da alta administração. Dentre os contratos terceirizados, optou-se por avaliar os serviços prestados referente ao contrato específico de limpeza. Identificou-se que a instituição A possui a contratação por posto de trabalho sem que haja uma avaliação especifica para a qualidade dos serviços prestados vinculado ao pagamento da fatura, mesmo com total abertura para projetos inovadores. Esse modelo de contratação, atualmente, supre com as demandas da instituição. Já as instituições B e C possuem a contratação com utilização de ANS. Apesar de possuírem obstáculos com relação à adoção de inovação, observou-se que essas duas instituições possuem um modelo diferenciado de gerir seus contratos com inovação em seu processo. Verificou-se que as três instituições conseguem atingir os objetivos esperados para os contratos apresentados tais como a qualidade na entrega dos serviços prestados e o correto pagamento da fatura com relação ao serviço executado. Apesar disso, como existe a possibilidade de contratar futuramente uma empresa que não atinja a qualidade esperada ou que não tenha a competência para tal, é importante avaliar a implantação do ANS nos contratos futuros. / This paper aims to evaluate the structure of three public institutions’ regarding the proposals for organisational innovation through changes in their work processes. This study includes third-party vendors contracts through a bidding process with the use of Service Level Agreements (ANS in Brazil), which has objectives evaluates contracts. This allows adjusting the payment of the contracts according to the quantity and quality of the services provided, constituting the innovative process to be studied in this work. For that, interviews with workers in areas from planning to execution of continued third-party contracts were conducted to check the perception of innovation in their institution, organisational culture and managers’ support. Among the outsourced contracts, we opted to evaluate the services referring to the specific cleaning contract. The institution A has the type of contract by workstation without specifically check the quality of services provided which were paid, even with possibility for innovative projects. This contracting model currently meets the demands of the institution A. Institutions B and C follows Service Level Agreements. Despite they usually reach an impasse on innovation process, it was noted that these two institutions follows a particular model to manage their contracts with innovation. It was verified that the three institutions achieves the goals expected for contracts provided, which consists in the quality of services provided, followed by the due payment. The evaluate of the employment of Service Level Agreements is important, because there are no guarantees that a future contract will reach the expected quality.

In der vorliegenden Masterarbeit wird die Thematik eines Service-Level-Modells für das Kunden-Reporting eines hochtechnologisierten Unternehmens analysiert. Die stetig kürzer werdenden Technologiezyklen, der zunehmende Druck von anderen Wettbewerbern sowie die Flut an aufkommenden Kleinkunden, durch Technologien des Internet der Dinge, verlangen nach einer konsequenten Report-Standardisierung. Aufgrund der unterschiedlichen Ansätze im Kunden-Reporting des Unternehmens wurde untersucht, inwiefern die Erfahrungen mit Großkunden auf Kleinkunden nachhaltig und zielgerichtet adaptiert werden können. Die Analyse der theoretischen Grundlagen unterstreicht die Relevanz dieser Thematik und verdeutlicht die Gemeinsamkeiten zwischen dem unternehmensinternen Management-Reporting sowie dem Reporting für B2B-Kunden. Im Anschluss daran erfolgt eine Bestandsaufnahme des Customer-Reportings in Bezug auf das Foundry-Unternehmen. Dabei wurden alle kundenrelevanten Berichte der Fachabteilungen begutachtet. Im Nachgang dazu konnten entsprechende Optimierungsansätze herausgearbeitet sowie ein nachhaltiges Reporting-Konzept für Kleinkunden aufgezeigt werden. Das erarbeitete Konzept soll zukünftig seitens der Foundry als Grundlage für aufkommende Neukunden mit niedrigem Produkt-Volumina dienen. Betrachtet man nun das Resultat dieser Untersuchung bleibt festzuhalten, dass durch dieses Instrument dem Effekt der Informationsüberflutung auf Kundenseite deutlich entgegengewirkt wird. Überdies wird erreicht, dass auf Seiten der Foundry sowie dem B2B-Kunden ein homogenes Verständnis, in Bezug auf die technischen Inhalte, generiert wird. Insgesamt betrachtet, liefert diese Arbeit einen wertvollen Beitrag zum Thema Customer-Reporting im hochtechnologisierten Umfeld. Man kann daher den Schluss ziehen, dass es gelingen kann, den vielfältigen Anforderungen der aufkommenden Kleinkunden mit einem generellen Reporting-Standard zu begegnen.

O objetivo deste estudo é realizar a avaliação da estrutura de três instituições públicas com relação às propostas de inovação organizacional por meio das mudanças em seus processos de trabalho. Este estudo abrange os contratos terceirizados realizados por meio de processo licitatório com a utilização de Acordo de Nível de Serviço (ANS), que possui critérios objetivos de mensuração dos resultados contratados. Isso permite adequar o pagamento das faturas dos contratos de acordo com a quantidade e qualidade dos serviços prestados, constituindo o processo inovativo a ser estudado neste trabalho. Para isso, foram realizadas entrevistas com servidores das áreas que atuam desde o planejamento até o acompanhamento e execução dos contratos terceirizados continuados de forma a verificar a percepção com relação à inovação em sua instituição, cultura organizacional e apoio da alta administração. Dentre os contratos terceirizados, optou-se por avaliar os serviços prestados referente ao contrato específico de limpeza. Identificou-se que a instituição A possui a contratação por posto de trabalho sem que haja uma avaliação especifica para a qualidade dos serviços prestados vinculado ao pagamento da fatura, mesmo com total abertura para projetos inovadores. Esse modelo de contratação, atualmente, supre com as demandas da instituição. Já as instituições B e C possuem a contratação com utilização de ANS. Apesar de possuírem obstáculos com relação à adoção de inovação, observou-se que essas duas instituições possuem um modelo diferenciado de gerir seus contratos com inovação em seu processo. Verificou-se que as três instituições conseguem atingir os objetivos esperados para os contratos apresentados tais como a qualidade na entrega dos serviços prestados e o correto pagamento da fatura com relação ao serviço executado. Apesar disso, como existe a possibilidade de contratar futuramente uma empresa que não atinja a qualidade esperada ou que não tenha a competência para tal, é importante avaliar a implantação do ANS nos contratos futuros. / This paper aims to evaluate the structure of three public institutions’ regarding the proposals for organisational innovation through changes in their work processes. This study includes third-party vendors contracts through a bidding process with the use of Service Level Agreements (ANS in Brazil), which has objectives evaluates contracts. This allows adjusting the payment of the contracts according to the quantity and quality of the services provided, constituting the innovative process to be studied in this work. For that, interviews with workers in areas from planning to execution of continued third-party contracts were conducted to check the perception of innovation in their institution, organisational culture and managers’ support. Among the outsourced contracts, we opted to evaluate the services referring to the specific cleaning contract. The institution A has the type of contract by workstation without specifically check the quality of services provided which were paid, even with possibility for innovative projects. This contracting model currently meets the demands of the institution A. Institutions B and C follows Service Level Agreements. Despite they usually reach an impasse on innovation process, it was noted that these two institutions follows a particular model to manage their contracts with innovation. It was verified that the three institutions achieves the goals expected for contracts provided, which consists in the quality of services provided, followed by the due payment. The evaluate of the employment of Service Level Agreements is important, because there are no guarantees that a future contract will reach the expected quality.

O nÃvel de serviÃo de uma empresa atacadista distribuidora pode ser medido pela frequÃncia e regularidade com que sua equipe de vendas atende os clientes. Mas como o sucesso no mercado tambÃm depende dos custos envolvidos, o planejamento adequado das sistemÃticas de atendimento à crÃtico. Aproveitando as similaridades entre essa situaÃÃo e o Problema de RoteirizaÃÃo PeriÃdica de VeÃculos (PRPV), foi proposta uma tÃcnica de resoluÃÃo deste problema. Para o PRPV, dado um horizonte de planejamento composto de vÃrios dias, clientes devem ter suas visitas alocadas aos dias conforme combinaÃÃes possÃveis ao mesmo tempo em que rotas sÃo geradas para cada dia, objetivando a reduÃÃo do custo total de atendimento nesse mesmo horizonte de planejamento. A tÃcnica proposta tambÃm foi adaptada para aplicaÃÃo no caso prÃtico de roteirizaÃÃo de uma equipe de vendas com horizonte de planejamento semanal e consiste em um algoritmo genÃtico para o qual foi desenvolvido um operador de cruzamento original. A tÃcnica foi validada com instÃncias da literatura para o PRPV e suas soluÃÃes para o caso prÃtico indicaram economias anuais significativas. / The service level of a wholesale distributor can be measured by the frequency and regularity with which its sales staff serves customers. But as the market success also depends on the costs involved, the proper planning of systematic servings is critical. Taking advantage of the similarities between this situation and the Periodic Vehicle Routing Problem (PVRP), a technique for solving the later was proposed. For the PVRP, given a planning horizon of several days, visits to customers must be assigned to possible days according to predefined schedule combinations at the same time as routes are generated for each day, aiming to reduce the total cost of serving in the same planning horizon. The proposed technique was also adapted to be applied to the practical case of routing a sales team within a weekly planning horizon and it consists of a genetic algorithm for which was developed an original crossover operator. The technique was validated with instances from the literature for the PVRP and its solutions for the case study indicated significant annual savings.

Nos tempos atuais, cada vez mais as organizações têm investido em equipamentos e infra-estrutura de educação a distância (EAD). Grande parte dos estudos até hoje realizados dizem respeito a aspectos pedagógicos relacionados a esse tipo de sistema produtivo. Contudo, há poucos estudos dedicados a sua gestão. Esta dissertação busca, por meio de uma pesquisa à literatura pertinente, seguida de uma pesquisa de campo, sistematizar o conhecimento sobre a gestão de um sistema de operações de EAD, buscando formas para otimizar sua disponibilidade operacional. Ao longo do trabalho, a disponibilidade é tratada com um indicador de resultado de duas diferentes funções da organização: função gestão de contratos e função manutenção. A primeira diz respeito ao acordo de nível de serviço (SLA) firmado entre a organização foco deste estudo e um fornecedor de serviços de telecomunicações. A segunda função compreende a forma como são adotadas abordagens ou políticas de manutenção para os equipamentos utilizados para a execução desse tipo de serviço. Assim, descreve-se o contexto em que se inserem a disponibilidade e as duas funções a ela relacionadas e buscam-se formas para coordenar essas funções com o objetivo de otimizar a disponibilidade operacional do sistema produtivo. Algumas proposições foram estruturadas e verificadas numa organização, através da metodologia científica pesquisa-ação. Um instrumento referencial foi elaborado para amparar a pesquisa de campo visando facilitar a verificação das proposições propostas, além de colaborar para melhor atingir os objetivos propostos. A conclusão da pesquisa revela que as proposições de estudo não se confirmaram de forma plena, apontando para um sensível distanciamento entre teoria e pratica organizacional, deixando, assim, espaço aberto para novos estudos. / In present days, organizations are investing increasingly in equipment and infrastructure for distance education (DE). Great part of the studies carried out until today focus on the pedagogical aspects related to this type of productive system. However, there are few studies dedicated to its management. It is the goal of this study, through research in specific literature followed by a field research, to systemize the knowledge on management of an operational system for DE, searching for ways to optimize its operational availability. Throughout the work, the availability is considered a result indicator for two different functions of the organization: contract management function and maintenance function. The former one says respect to the service level agreement (SLA) firmed between the organization, focus of this study, and a supplier of telecommunications services. The latter is concerned with the ways that maintenance approaches and politics for the equipment involved in the execution of this type of service are adopted. Thus, the context in which the availability and both related functions are enclosed has been described and ways to co-ordinate these functions with the goal of optimizing the productive system operational availability is searched. The framework of some proposals was developed and verified in an organization through the scientific methodology ?Action Research?. A reference instrument was elaborated to support the field research aiming to ease the verification of the proposals that have been made, besides helping to achieve the proposed goal. The research conclusion discloses that the study proposals weren?t fully confirmed, leading to a considerable withdraw between organizational theory and practice, leaving, thus, an open space for new studies.