Nürnberg, Universiẗat, Diss., 2005--Erlangen.

Σε αυτή την διπλωματική εργασία θα εξετάσουμε τα web services. Μια σχετικά νέα και αναπτυσσόμενη τεχνολογία. Θα δούμε τι ακριβώς είναι τα web services, θα εξετάσουμε την βασική αρχιτεκτονική τους και κάποια δομικά τους στοιχεία που είναι αρκετά συνήθη πλέον. Θα μιλήσουμε περί XML, WSDL, UDDI, ενώ θα επικεντρωθούμε στα SOAP Web Services. Στην συνέχεια θα τα εξετάσουμε από την πλευρά της ασφάλειας. Σίγουρα το θέμα της ασφάλειας των web εφαρμογών δεν είναι απλό ούτε μπορεί να αναλυθεί επαρκώς σε μερικές σελίδες μονάχα. Ο τομέας της ασφάλειας web εφαρμογών και web services είναι ένας τομέας ο οποίος εξελίσσεται δυναμικά. Πόσο μάλλον ο τομέας των web services, τα οποία εξελίσσονται και αυτά συνεχώς, οπότε αναμενόμενα όσο αναπτύσσονται νέες τεχνολογίες κι εξερευνούνται διαφορετικές προσεγγίσεις, συνεχώς ανακαλύπτονται νέες αδυναμίες απ’όπου μπορεί να παραβιαστεί το κάθε σύστημα, η κάθε εφαρμογή και υπηρεσία. Θα δημιουργήσουμε ένα SOAP web service σε PHP πλατφόρμα, μια ελάχιστα διαδεδομένη περίπτωση web service και θα εξετάσουμε τρόπους με τους οποίους μπορούμε να ενισχύσουμε την ασφάλεια και να προστατέψουμε το συγκεκριμένο service. Είναι μια περίπτωση στην οποία δεν μπορούμε να χρησιμοποιήσουμε τα διαδεδομένα πρωτόκολλα που έχουν τα web services για την ενίσχυση της ασφάλειάς τους, οπότε θα χρειαστεί να αναζητήσουμε δικούς μας “custom” τρόπους για την διαφύλαξη της ασφάλειας του service μας. / -

Η λύση και η βελτιστοποίηση πραγματικών προβλημάτων, δηλαδή προβλημάτων τα οποία συναντάμε στην καθημερινή μας ζωή είναι συχνά περίπλοκη και παρουσιάζει πολλές δυσκολίες, η μοντελοποίησή τους εξελίσσεται συνεχώς σε θέματα περιορισμών και στόχων και η ανάλυσή τους απαιτεί πολύ χρόνο και επεξεργαστική ισχύ. Υπάρχουν διάφοροι αλγόριθμοι και μέθοδοι που επιδιώκουν την επίλυση τέτοιων προβλημάτων. Στην κατηγορία αυτή ανήκουν και οι μεταευρετικές μέθοδοι (metaheuristics) οι οποίες επιτρέπουν την αντιμετώπιση προβλημάτων μεγάλου μεγέθους παραδίδοντας ικανοποιητικές λύσεις σε λογικό χρόνο. Ωστόσο, παρά τη μείωση της πολυπλοκότητας που επιτρέπουν οι μεταευρετικές μέθοδοι, συχνά δεν είναι επαρκείς για την αντιμετώπιση μεγάλων προβλημάτων. Ο υπολογισμός πλέγματος (Grid computing), ο οποίος έχει έρθει πρόσφατα στο προσκήνιο, παρέχει σημαντική βοήθεια στην επίλυση δύσκολων, με σκληρές απαιτήσεις χρόνου προβλημάτων. Στην παρούσα διπλωματική χρησιμοποιούμε μεταευρετικές μεθόδους σε υπολογιστικά πλέγματα για την επίλυση ενός σύνθετου προβλήματος χρονοπρογραμματισμού εξετάσεων Πανεπιστημίου, το οποίο δημοσιεύτηκε από τον Διεθνή Διαγωνισμό Χρονοπρογραμματισμού το 2007. / -

Σκοπός αυτής της εργασίας είναι η αναφορά και ανάλυση των υπαρχουσών τεχνολογιών με τις οποίες είναι δυνατή η κατασκευή ενός web service. Η γλώσσα XML καθώς και οι WSDL, UDDI και SOAP είναι οι βασικές τεχνολογίες που χρησιμοποιούνται για την κατασκευή των web services και αναλύονται λεπτομερώς με παραδείγματα, για την πλήρη κατανόησή τους / Τhe aim of this paper is to to analyse the current technology, we can construct a web service. XML, WSDL, UDDI and SOAP are the main tools we use to built a web service

There has been an increased focus in recent years on the development of re-usable software, in the form of objects and software components. This increase, together with pressures from enterprises conducting transactions on the Web to support all business interactions on all scales, has encouraged research towards the development of easily reconfigurable and highly adaptable Web services. This work investigates the ability of Component-Based Software Development (CBSD) to produce such systems, and proposes a more manageable use of CBSD methodologies. Component-Driven Software Development (CDSD) is introduced to enable better component manageability. Current Web service technologies are also examined to determine their ability to support extensible Web services, and a dynamic Web service architecture is proposed. The work also describes the development of two proof-of-concept systems, DREW Chat and Hamilton Bank. DREW Chat and Hamilton Bank are implementations of Web services that support extension dynamically and at run-time. DREW Chat is implemented on the client side, where the user is given the ability to change the client as required. Hamilton Bank is a server-side implementation, which is run-time customisable by both the user and the party offering the service. In each case, a generic architecture is produced to support dynamic Web services. These architectures are combined to produce CREWS, a Component-driven Runtime Extensible Web Service solution that enables Web services to support the ever changing needs of enterprises. A discussion of similar work is presented, identifying the strengths and weaknesses of our architecture when compared to other solutions.

This thesis presents a scalable service-oriented architecture for the demand-driven deployment of location-neutral software services, using an end-to-end or ‘holistic’ approach to address identified shortcomings of the traditional Web Services model. The architecture presents a multi-endpoint Web Service environment which abstracts over Web Service location and technology and enables the dynamic provision of highly-available Web Services. The model describes mechanisms which provide a framework within which Web Services can be reliably addressed, bound to, and utilized, at any time and from any location. The presented model eases the task of providing a Web Service by consuming deployment and management tasks. It eases the development of consumer agent applications by letting developers program against what a service does, not where it is or whether it is currently deployed. It extends the platform-independent ethos of Web Services by providing deployment mechanisms which can be used independent of implementation and deployment technologies. Crucially, it maintains the Web Service goal of universal interoperability, preserving each actor’s view upon the system so that existing Service Consumers and Service Providers can participate without any modifications to provider agent or consumer agent application code. Lastly, the model aims to enable the efficient consumption of hosting resources by providing mechanisms to dynamically apply and reclaim resources based upon measured consumer demand.

Utvecklingen går mot alltmer distribuerade IT-system, där ett flertal datorer kommunicerar med varandra. Detta gäller även försvarsmaktens ledningssystem. I dessa öppna och distribuerade system är olika säkerhetsfunktioner kritiska. En av dessa är att kunna verifiera identiteten hos den part som kommunikationen sker med. Detta görs oftast med hjälp av asymmetriska kryptooperationer, där identiteter kan verifieras med hjälp av öppet publicerade autentiseringsnycklar. Hanteringen av sådana nycklar kan centraliseras med hjälp av XML Key Management Specification. XKMS är en standard utvecklad av W3C som specificerar en Web Service för hantering av distribution, verifiering och registrering av öppna nycklar. I detta examensarbete har en del av en sådan service implementerats. Fokus har legat på distribution och verifikation av X.509-certifikat som är en ledande standard för att knyta ihop identiteter med nycklar. Slutligen har ett API till Java utvecklats för att på klientsidan underlätta nyttjandet av en XKMS-service.

Made available in DSpace on 2014-06-12T15:51:59Z (GMT). No. of bitstreams: 1 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Tradicionalmente, soluções para controle e automação de ambientes são providas por um fornecedor, utilizando um padrão de comunicação quase sempre fechado e de alto custo. Além disso, muitas destas soluções oferecem alternativas limitadas de controle. A possibilidade de gerenciar ambientes através de diversas tecnologias simultaneamente contribuirá para o aumento do conforto, segurança e qualidade de vida dos usuários, tornando-se um ponto crucial para uma maior difusão da automação doméstica. Entre as vantagens de um ambiente automatizado pode-se citar a contribuição para o processo de inclusão digital dos portadores de necessidades especiais e/ou idosos. O trabalho em questão consiste na proposta de um framework para controle de ambientes e dispositivos distribuídos envolvendo tecnologias como: UPnP, Web Services, Comandos de voz e GPRS dentre outras. Com o objetivo de atender a esses requisitos, foram desenvolvidos módulos e aplicações em Java® e .Net® para serem executados num servidor e em dispositivos móveis e sistemas embarcados

Orientador: Dalton Soares Arantes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-08T23:55:19Z (GMT). No. of bitstreams: 1 Cruz_AriadneArrais_M.pdf: 3860163 bytes, checksum: 0d7d8da694df81c51baff9f2d0088e8c (MD5) Previous issue date: 2007 / Resumo: O objetivo deste trabalho é apresentar um framework genérico e extensível para integração de WebLabs e outros Serviços via Web. Esta integração visa promover uma colaboração acadêmica em diferentes áreas da ciência, oferecendo aos desenvolvedores uma infra-estrutura básica de serviços, tais como uma comunicação cliente/servidor, serviços de persistência e facilidades para o desenvolvimento de interfaces de usuários. Infra-estruturas como esta viabilizam o compartilhamento de experimentos reais e remotos, explorando o novo paradigma de WebLab. O framework proposto é baseado em uma arquitetura modular e utiliza o conceito de plugins pré-instalados. Esta abordagem é bastante flexível, permitindo aos administradores do framework adicionar, remover ou atualizar seus serviços WebLabs sem a necessidade de recompilar o núcleo da plataforma ou de interromper os serviços. Isso garante um maior compartilhamento de código e facilidade de manutenção. O framework foi implementado utilizando metodologias do estado-da-arte, incluindo técnicas de programação avançadas como os Padrões de Projeto e o paradigma Ajax / Abstract: The objective of this work is to present a generic and extensible Framework for WebLab integration. Such integration aims at fostering academic collaboration in different areas of science, since it offers a basic service infrastructure to developers, such as client/server communication, persistency service and facilities for the development of user-friendly interfaces. An infrastructure such as this one is of great importance for scientists to share virtual and real remote experiments through the web. The proposed Framework is based on a modular architecture that uses the concept of preinstalled plugins. This approach is quite flexible, since it allows the Framework administrator to add, remove or upgrade the WebLab services without recompilation of the platform kernel or disruption of services. This guarantees a better code-sharing and an easier Framework maintenance. The Framework was implemented using state-of-the-art methodology and other advanced programming techniques, such as Design Patterns and Ajax / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

A velocidade das mudanças e a necessidade de informações disponíveis em vários meios têm feito com que os sistemas atuais se integrem cada vez mais. Neste cenário, arquiteturas orientadas a serviços e Web Services ganham evidência. Por utilizarem padrões já bem difundidos, por exemplo XML (extended markup language), Web Services se destacam pela interoperabilidade e dinamismo, disponibilizados através da Internet e utilizado em ambientes heterogêneos. Contudo, isso afeta significativamente atributos não funcionais, por exemplo, confiabilidade, disponibilidade, entre outros. Para Web Services, além de todos os problemas existentes no paradigma de programação distribuída, temos ainda o problema de que erros em um determinado serviço não devem ser propagados para os demais. Dentre as diversas formas de se contornar o problema, existe a definição de padrões transacionais que visam delinear regras específicas para a comunicação entre os serviços. O objetivo do trabalho é identificar casos de testes que permitam validar a adequação, tanto do serviço quanto da aplicação de padrões definidos, de modo a garantir uma maior confiabilidade do sistema como um todo. Para isso, é avaliada a aplicabilidade de técnicas de perturbação e mutação de dados com relação ao padrão estabelecido. Como resultado, obtém-se um subconjunto das técnicas que possuem potencial de identificação de falhas nesse cenário. / Software technology has become essential since it is available in most places. Powered by Internet, nowadays, information quickly flows throw systems. Web Services provide a standard way to meet these objectives, as they use common communication pattern like XML and HTTP. The use of Web Services brings many benefits. On the other hand, it also brings some issues about reliability, availability and other non functional problems. Transactional patterns are an alternative to outline such problems. This study aims to find an effective way to certificate the correct use of those patterns by applying perturbation and mutation testing techniques. As work result, it is expected to determine which of techniques are applicable.