Dynamic Context-Aware Service Composition, Brokerage and Monitoring in Service-Oriented Computing

服务组合长期以来一直是一个活跃的研究领域，它使服务代理能够生成适合客户复杂需求的组合服务。 众所周知的个体问题，如约束满足、上下文感知、数据集成和数据隐私，都在文献中找到了各种独立的解决方案。然而，从更广泛的角度来看，这些问题实际上是相互交织的，它们的相互作用产生了单独解决方案无法解决的其他问题。我们的解决方案为所有这些问题的整体解决方案提供了坚实的理论基础。 ******《金融邮报》2017 年 3 月的一篇文章报道称，由于国际电子商务未能征税，加拿大政府每年可能损失高达 1.3B$ 的税收。这个问题源于这样一个事实：参与国际电子商务的服务提供商不能意识到，也不能有权应用适用于他们提供服务的每个客户的特定背景的所有国际限制/政策/法规。 ******此外，电子商务倾向于为能够承担与其他公司在线服务合作投资的大公司创造更多业务量。通过上下文/约束意识增强的自动化服务组合可以帮助更专业和与商业无关的服务提供商接触到他们的客户。例如，在对交易应用国际政策后，与本地服务提供商的交易可能比与外国服务提供商的交易更合适。因此，拥有约束/策略/上下文管理的集成解决方案将有可能促进上下文专业化（例如本地）服务提供商的经济可行性。******从各个角度来看，上述问题都与综合服务上集成数据模型的自动操作有关。尽管存在这样的共同点，但这些问题尚未找到适当的综合解决方案。更具体地说，针对组合服务中的约束感知问题提供了各种解决方案。然而，它们都将约束视为整个组合服务固有的，而不考虑它们可以应用组合服务的哪一部分。此外，现有的解决方案都没有提供考虑不同来源的约束，特别是外部定义的约束的集成解决方案。 ******该项目旨在为服务组合过程以及组合服务的执行开发新的集成约束/上下文感知模型。该模型基于可能世界语义的概念，其中计算上下文和约束在多维上下文空间上建模。

Service composition has long been an active research domain that enables a service broker to generate a composite service adapted to the complex needs of their clients. Well-known individual problems such as constraint satisfaction, context-awareness, data integration, and data privacy have all found various independent solutions in the literature. However, a broader look at the situation reveals that these problems are in fact interwoven and their interaction creates other problems that individual solutions cannot solve. Our solution proposes a sound theoretical basis to an integrated solution to all these problems as a whole. ******An article from the Financial Post reported in March 2017 that the Government of Canada is potentially losing up to 1.3B$ yearly in taxation revenue due to international e-commerce failing to charge taxes. This problem stems from the fact that service providers involved in international e-commerce cannot be expected to be aware, nor have authority to apply all international constraints/policies/regulations that apply to the specific context of every customer to which they provide a service. ******Furthermore, e-commerce has a tendency to create more business volume to larger companies that can afford investments in online service collaboration with other companies. Automated service composition augmented with context/constraint-awareness can help more specialized and commercially unconnected service providers to reach for their clientele. For example, a transaction with a local service may prove to be more appropriate compared with a transaction with a foreign service provider after international policies are applied to a transaction. Having an integrated solution for constraint/policy/context management would thus potentially foster the economic viability of contextually specialized (e.g. local) service providers.******The problems stated above are all related, from various perspectives, to the automated manipulation of an integrated data model over the composite service. Despite this common denominator, these problems have not met with an appropriately integrated solution. More specifically, various solutions were provided to the problem of constraint-awareness in composite services. However, they all consider constraints as being inherent to the whole composite service without consideration which part of the composite service they may apply. Also, none of the existing solutions provide an integrated solution considering different sources of constraints, especially externally-defined constraints. ******This project aims at the development of a new integrated constraint/contextual-aware model for the service composition process, as well as for the execution of composite services. This model is based on the notion of possible-worlds semantics, where the computational context and the constraints are modeled over a multidimensional context space.