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应客户复杂需求的组合服务。 众所周知的个人问题，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，这些问题实际上是交织在一起的，它们的相互作用产生了其他问题，而这些问题是单独的解决方案无法解决的。我们的解决方案为所有这些问题的整体综合解决方案提供了良好的理论基础。** 2017年3月，《金融邮报》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13亿美元的税收。这一问题产生的原因是，不能指望参与国际电子商务的服务提供者了解，也不能指望他们有权适用于他们向其提供服务的每一个客户的具体情况的所有国际限制/政策/条例。** 此外，电子商务有一种趋势，即为那些能够负担得起与其他公司进行在线服务合作投资的大型公司创造更多的业务量。自动化的服务组合增强了上下文/约束意识，可以帮助更专业和商业上不连接的服务提供商，以达到他们的客户。例如，在对交易适用国际政策后，与当地服务的交易可能比与外国服务提供者的交易更合适。因此，拥有约束/政策/背景管理的综合解决方案将有可能促进背景专业化（例如当地）服务提供商的经济可行性。从不同的角度来看，上述问题都与在组合服务上自动操作集成数据模型有关。尽管有这一共同点，但这些问题尚未得到适当的综合解决。更具体地说，提供了各种解决方案，在组合服务的约束意识的问题。然而，它们都认为约束是整个组合服务所固有的，而没有考虑它们可以应用组合服务的哪一部分。而且，现有的解决方案中没有一个提供考虑不同约束源（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一个新的集成约束/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.