Cloud computing is no longer the future but the present. Every day, more and more companies and service providers transfer their businesses and operations to the cloud, benefiting from its multiple advantages. Moreover, the flexibility offered by many cloud services allows to easily build sophisticated services by just composing simpler ones, rather than creating them from zero. Yet, to mitigate potential security threats and keep the maximum performance at any time, a smart selection of those composite services constitutes a key aspect. In this paper, we introduce the reader to the problem of Web service selection based on their reputation scores and subsequently present a survey on some of the most relevant reputation-based Web service orchestration schemes for cloud computing in the literature. For each one of these approaches, a thorough analysis of their pros and cons has been performed, providing a comprehensive comparison amongst all of them leading to the conclusion that, to the best of our knowledge, there is no one single model elegantly fitting to each and every situation that could occur in such a dynamic environment like cloud computing. Finally, we present some current challenges and future research trends in the field of reputation-based service orchestration in cloud computing.Yet, to create a successful composite service, such as when building a puzzle, the correct pieces need to be chosen. For one or another reason (failure, malware, exhausted resources, etc), the individual services composing the bigger one might unexpectedly change their behaviour throughout time [10,11], degrading their performance (and, in turn, the performance of the composite service) or even constituting a security threat or breach. Therefore, it is a wise strategy not to base a composite service on fixed simpler ones, but rather making the latter replaceable whenever needed in order to keep always the maximum performance and level of assurance.Trust and reputation management has emerged in the last years as a smart and accurate solution to tackle these issues [12][13][14][15]. Actually those systems have been widely accepted and deployed, finding them in a multitude of different environments and scenarios [16,17]. This appealing area of knowledge has captured the attention of both industry and academia, leading to several successful products [13] and patents [18][19][20][21][22][23].In this paper, we performed a survey of some of the main research approaches dealing with the problem of reputation-based Web service (WS) orchestration for cloud computing environments. We described each of those solutions, thoroughly analysing their advantages and shortcomings. Moreover, a comprehensive comparative amongst them led us to the conclusion that none of the studied models gracefully fits to each and every situation that could emerge in a highly dynamic environment such as cloud computing. Finally, we also studied some current research challenges, as well as future trends in the field of reputation-based service orchestration in ...

The creation of new service revenue streams supported by consistent user experiences is one of the topics for the future service layer. Personalization over real-time decision enablement is one important option to explore for new business models. The paper introduces a novel personalization communication control mechanism across services, devices and platforms realizing realtime decision enablement for an IMS-based SDP environment, accompanied with marketing, standards and detailed technology studies.

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