Intelligent business processes composition based on mas, semantic and cloud integration (IPCASCI)

[EN]Component reuse is one of the techniques that most clearly contributes to the evolution of the software industry by providing efficient mechanisms to create quality software. Reuse increases both software reliability, due to the fact that it uses previously tested software components, and development productivity, and leads to a clear reduction in cost. Web services have become are an standard for application development on cloud computing environments and are essential in business process development. These services facilitate a software construction that is relatively fast and efficient, two aspects which can be improved by defining suitable models of reuse. This research work is intended to define a model which contains the construction requirements of new services from service composition. To this end, the composition is based on tested Web services and artificial intelligent tools at our disposal. It is believed that a multi-agent architecture based on virtual organizations is a suitable tool to facilitate the construction of cloud computing environments for business processes from other existing environments, and with help from ontological models as well as tools providing the standard BPEL (Business Process Execution Language). In the context of this proposal, we must generate a new business process from the available services in the platform, starting with the requirement specifications that the process should meet. These specifications will be composed of a semi-free description of requirements to describe the new service. The virtual organizations based on a multi-agent system will manage the tasks requiring intelligent behaviour. This system will analyse the input (textual description of the proposal) in order to deconstruct it into computable functionalities, which will be subsequently treated. Web services (or business processes) stored to be reused have been created from the perspective of SOA architectures and associated with an ontological component, which allows the multi-agent system (based on virtual organizations) to identify the services to complete the reuse process. The proposed model develops a service composition by applying a standard BPEL once the services that will compose the solution business process have been identified. This standard allows us to compose Web services in an easy way and provides the advantage of a direct mapping from Business Process Management Notation diagrams

Placements of virtual network functions for effective network functions virtualization

In the future wireless networks, network function virtualization will lay the foun- dation for establishing a new resource management framework to e ciently utilize network resources. The rst part of this thesis deals in the minimization of the to- tal latency for a network and how to solve it e ciently. A model of users, Virtual Network Functions (vNFs) and hosting devices have been considered and was used to nd the minimum latency using Integer Linear Programming (ILP). The problem is NP-hard and takes exponential time to solve in the worst case. A Stable Matching based heuristic has been proposed to solve the problem in polynomial time and then the local search is utilized to improve the e ciency of the result. The second part of this thesis proposes the problem of fair allocation of the vNFs to hosting devices. A mathematical programming based model (ILP) has been designed to solve the problem which takes exponential time to solve in the worst case, due to its NP-hard nature. Thus an heuristic approach has been provided to solve the problem in polynomial time

Servidores móveis em redes AD HOC

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação.A arquitetura web services permite que aplicações desenvolvidas em diferentes plataformas interajam com o intuito de trocar dados e realizar tarefas sobre a rede mesmo em ambientes heterogêneos. A arquitetura utiliza uma pilha de padrões entre os quais destacam-se três: WSDL, linguagem utilizada para descrever o serviço, SOAP, protocolo que encapsula as mensagens XML trocadas pela rede e UDDI, mecanismo que age como um repositório de web services, todos com base na linguagem XML. As redes Ad hoc possuem como principal característica uma formação rápida e temporária. Por não necessitar de infra-estrutura fixa, essas redes são estabelecidas rapidamente em locais onde as redes fixas teriam dificuldade ou até mesmo a impossibilidade de serem instaladas. Nessas redes, os nodos comunicam-se diretamente sem a necessidade de infra-estrutura fixa, sendo eles próprios responsáveis pelo roteamento dos pacotes. Este trabalho de pesquisa apresenta um modelo que visa possibilitar a execução de web services em redes Ad hoc. Tendo em vista a usual carência de serviços que os usuários dessas redes possuem, nossa contribuição permite a tais usuários dispor do acesso a alguns serviços, que geralmente estão disponíveis apenas na rede fixa, restringindo o acesso aos serviços móveis à área de cobertura alcançada por essas redes. Nos últimos anos, os dispositivos móveis a capacidade de processamento e armazenamento aumentaram significantemente, o que torna possível, atualmente, a execução de um conjunto relativamente grande de serviços. Por esta razão, assumimos como objetivo principal deste trabalho possibilitar a qualquer dispositivo móvel, conectado a uma rede Ad hoc, o oferecimento de serviços a quaisquer outros dispositivos na mesma rede, tornando-o um servidor móvel. O funcionamento do modelo tem como principal característica o fato de disponibilizar serviços sem que o usuário dependa do auxílio de qualquer infra-estrutura fixa no momento da execução desses serviços. Uma vez concluída essa etapa, o usuário móvel tem autonomia suficiente para coordenar sua função de fornecer os serviços em momentos e locais apropriados. Nossos resultados experimentais indicam que o modelo possui claras vantagens ao ser utilizado em redes Ad hoc. Dentre elas, destacamos o fato de explorar as características desses ambientes com a execução do serviço de modo Ad hoc, levando de fato, serviços a qualquer lugar

A Review on Cloud Computing: Design Challenges in Architecture and Security

Cloud computing is becoming a powerful network architecture to perform large-scale and complex computing.In this paper, we will comprehensively survey the concepts and architecture of cloud computing, as well as its security and privacy issues. We will compare different cloud models, trust/reputation models and privacy-preservation schemes. Their pros and cons are discussed for each cloud computing security and architecture strategy

An Autonomic Cross-Platform Operating Environment for On-Demand Internet Computing

The Internet has evolved into a global and ubiquitous communication medium interconnecting powerful application servers, diverse desktop computers and mobile notebooks. Along with recent developments in computer technology, such as the convergence of computing and communication devices, the way how people use computers and the Internet has changed people´s working habits and has led to new application scenarios. On the one hand, pervasive computing, ubiquitous computing and nomadic computing become more and more important since different computing devices like PDAs and notebooks may be used concurrently and alternately, e.g. while the user is on the move. On the other hand, the ubiquitous availability and pervasive interconnection of computing systems have fostered various trends towards the dynamic utilization and spontaneous collaboration of available remote computing resources, which are addressed by approaches like utility computing, grid computing, cloud computing and public computing. From a general point of view, the common objective of this development is the use of Internet applications on demand, i.e. applications that are not installed in advance by a platform administrator but are dynamically deployed and run as they are requested by the application user. The heterogeneous and unmanaged nature of the Internet represents a major challenge for the on demand use of custom Internet applications across heterogeneous hardware platforms, operating systems and network environments. Promising remedies are autonomic computing systems that are supposed to maintain themselves without particular user or application intervention. In this thesis, an Autonomic Cross-Platform Operating Environment (ACOE) is presented that supports On Demand Internet Computing (ODIC), such as dynamic application composition and ad hoc execution migration. The approach is based on an integration middleware called crossware that does not replace existing middleware but operates as a self-managing mediator between diverse application requirements and heterogeneous platform configurations. A Java implementation of the Crossware Development Kit (XDK) is presented, followed by the description of the On Demand Internet Computing System (ODIX). The feasibility of the approach is shown by the implementation of an Internet Application Workbench, an Internet Application Factory and an Internet Peer Federation. They illustrate the use of ODIX to support local, remote and distributed ODIC, respectively. Finally, the suitability of the approach is discussed with respect to the support of ODIC

A secure client / server interface protocol for the electricity prepayment vending industry

Electricity prepayment systems have been successfully implemented by South Africa’s national electricity utility (Eskom) and local municipalities for more than 17 years. The prepayment vending sub-system is a critical component of prepayment systems. It provides convenient locations for customers to purchase electricity. It predominantly operates in an “offline” mode, however, electricity utilities are now opting for systems that operate in an “online” mode. “Online” mode of operation or online vending is when a prepayment token is requested from a centralised server that is remote from the client at the actual point of sale (POS). The token is only generated by the server and transferred to the POS client, once the transaction, the POS client and the payment mechanism has been authenticated and authorised. The connection between the POS client and the server is a standard computer network channel (like Internet, direct dial-up link, X.25, GPRS, etc) The lack of online vending system standardisation was a concern and significant risk for utilities, as they faced the problem of being locked into proprietary online vending systems. Thus the South African prepayment industry, lead by Eskom, initiated a project to develop an industry specification for online vending systems. The first critical project task was a current state analysis of the South African prepayment industry, technology and specifications. The prepayment industry is built around the Standard Transfer Specification (STS). STS has become the de-facto industry standard to securely transfer electricity credit from a Point of Sale (POS) to the prepaid meter. STS is supported by several “offline” vending system specifications. The current state analysis was followed by the requirements analysis phase. The requirements analysis confirmed the need for a standard interface protocol specification rather than a full systems specification. The interface specification focuses on the protocol between a vending client and vending server and does not specify the client and server application layer functionality and performance requirements. This approach encourages innovation and competitiveness amongst client and server suppliers while ensuring interoperability between these systems. The online vending protocol design was implemented using the web services framework and therefore appropriately named, XMLVend. The protocol development phase was an iterative process with two major releases, XMLVend 1.22 and XMLVend 2.1. XMLVend 2.1 is the current version of the protocol. XMLVend 2.1 addressed the shortcomings identified in XMLVend 1.22, updated the existing use cases and added several new use cases. It was also modelled as a unified modelling language (UML) interface or contract for prepayment vending services. Therefore, clients using the XMLVend interface are able to request services from any service provider (server) that implements the XMLVend interface. The UML modelled interface and use case message pairs were mapped to Web Service Definition Language (WSDL) and schema (XSD) definitions respectively. XMLVend 2.1 is a secure and open web service based protocol that facilitates prepayment vending functionality between a single logical vending server and ‘n’ number of clients. It has become a key enabler for utilities to implement standardised, secure, interoperable and flexible online vending systems. AFRIKAANS : Voorafbetaalde elektrisiteitstelsels is suksesvol deur Suid-Afrika se nasionale elektrisiteitsverskaffer (Eskom) en plaaslike munisipaliteite geïmplementeer vir meer as 17 jaar. Die Voorafbetaal verkoop-subsisteem is 'n esensiële komponent van voorafbetaal elektrisiteitstelsels. Dit laat gebruikers toe om elektrisiteit te koop by ‘n verskeidenheid van verkooppunte. In die verlede het hierdie stelsels meestal bestaan as alleenstaande verkooppunte maar elektrisiteitsverskaffers is besig om hulle stelsels te verander om in n aanlyn modus te werk. Aanlyn verkoop is wanneer 'n voorafbetaalkoepon versoek word vanaf ‘n sentrale bediener wat vêr verwydered is van die kliënt se verkooppunt. Die koepon word slegs gegenereer deur die bediener en gestuur aan die kliënt nadat die transaksie, die kliënt self, en die betaling meganisme, gemagtig is. Die koppeling tussen verkooppuntkliënt en die bediener is ‘n standaard kommunikasie kanaal, (byvoorbeeld; Internettoegang, direkte inbel skakel, X.25 en “GPRS”) Die gebrek aan 'n standaard vir aanlynverkoopstelsels was 'n bekommernis en beduidende risiko vir elektrisiteitsverskaffers, aangesien hulle ‘n probleem ondervind dat hulle ingeperk sal word tot ‘n eksklusiewe ontwerp vir so ‘n aanlynverkoopstelsel. Dus het die Suid Afrikaanse voorafbetaal industrie, gelei deur Eskom, 'n projek begin om 'n industriespesifikasie te ontwikkel vir aanlyn verkoopstelsels. Die eerste kritiese projek taak was 'n analise van die huidige stand van die Suid-Afrikaanse vooruitbetaling industrie, die tegnologie en spesifikasies. Die voorafbetaal sektor is gebou rondom die Standaard Oordrag Spesifikasie, bekend as “Standard Transfer Specification” (STS). STS word algemeen aanvaar as die industrie standaard vir die oordrag van elektrisiteit krediet vanaf 'n Verkooppunt na die voorafbetaalmeter. STS word ondersteun deur verskeie alleenstaande verkoopstelsel spesifikasies. Die analise vir die huidige status was opgevolg deur ‘n studie van die vereistes vir so ‘n stelsel. Die vereistes analise het die behoefte bevestig vir 'n standaard koppelvlak protokol spesifikasie, eerder as 'n nuwe spesifikasie vir ‘n volledige oorafbetaalstelsel. Dit bepaal alleenlik die protokol koppelvlak tussen 'n voorafbetaalkliënt en die bediener. Dit spesifiseer nie die program vlak funksionaliteit of prestasie vereistes, vir die kliënt en bediener nie. Hierdie benadering bevorder innovasie en mededingendheid onder kliënt- en bediener-verskaffers, terwyl dit nog steeds verseker dat die stelsels wedersyds aanpasbaar bly. Die aanlyn verkoopprotokol ontwerp is geïmplementeer met die webdienste raamwerk en staan bekend as XMLVend. Die protokol vir die ontwikkeling fase was 'n iteratiewe proses met die twee groot weergawes, XMLVend 1.22 en XMLVend 2.1. Die huidige weergawe van die protokol - XMLVend 2.1, adresseer die tekortkominge wat geïdentifiseer is met XMLVend 1.22, terwyl dit ook die bestaande gebruiksgevalle opdatteer en verskeie nuwe gebruiksgevalle byvoeg. Dit was ook geskoei as 'n verenigde modelleringtaal (UML) koppelvlak, of 'n kontrak, vir die voorafbetaal verkoopsdienste. Kliënte is daarom in staat om, met behulp van die XMLVend koppelvlak, dienste te versoek van enige diensverskaffer wat die XMLVend koppelvlak ondersteun. Die UML gemodelleerde koppelvlak- en gebruiksgevalle- boodskappare was gemodeleer in die Web Dienste Definisie Taal (WSDL) en skema (XSD) definisies onderskeidelik. XMLVend 2.1 is 'n sekure en oop webdienste-gebaseerde protokol wat dit moontlik maak om voorafbetaalfunksies te fasilliteer tussen 'n enkele logiese verkoopbediener en 'x' aantal kliënte. Dit het 'n sleutelrol aangeneem vir verskaffers om ‘n gestandaardiseerde, veilige, wedersyds-aanpasbare en buigsame aanlyn verkoopstelsels moontlik te maak. CopyrightDissertation (MSc)--University of Pretoria, 2010.Electrical, Electronic and Computer Engineeringunrestricte