Management of Changes in Web Service Protocols

Lecture Notes in Computer Science, 2004

In the area of Web services and service-oriented architectures, business protocols are rapidly gaining importance and mindshare as a necessary part of Web service descriptions. Their immediate benefit is that they provide developers with information on how to write clients that can correctly interact with a given service or with a set of services. In addition, once protocols become an accepted practice and service descriptions become endowed with protocol information, the middleware can be significantly extended to better support service development, binding, and execution in a number of ways, considerably simplifying the whole service life-cycle. This paper discusses the different ways in which the middleware can leverage protocol descriptions, and focuses in particular on the notions of protocol compatibility, equivalence, and replace-ability. They characterise whether two services can interact based on their protocol definition, whether a service can replace another in general or when interacting with specific clients, and which are the set of possible interactions among two services.

Data & Knowledge Engineering, 2006

In the area of Web services and service-oriented architectures, business protocols are rapidly gaining importance and mindshare as a necessary part of Web service descriptions. Their immediate benefit is that they provide developers with information on how to write clients that can correctly interact with a given service or with a set of services. In addition, once protocols become an accepted practice and service descriptions become endowed with protocol information, the middleware can be significantly extended to better support service development, binding, and execution in a number of ways, considerably simplifying the whole service lifecycle. This paper discusses the different ways in which the middleware can leverage protocol descriptions, and focuses in particular on the notions of protocol compatibility, equivalence, and replaceability. They characterize whether two services can interact based on their protocol definition, whether a service can replace another in general or when interacting with specific clients, and which are the set of possible interactions among two services.

Service-oriented computing and applications, 2016

We investigate the problem of web service instances migration in the context of business protocol evolution, i.e., how to convert active instances of web services from an old version of a business protocol into a new one? We propose a framework based on a declarative approach to support service providers in defining fine-grained migration strategies of active instances. While the existing approaches for instances migration force the migrated instances to reflect the original ones as accurately as possible, in our approach we give to service providers the ability to declaratively define the constraints that drive the instances migration process. A migration strategy is expressed as a set of instances migration rules which are specified using an instance mapping language made of a set of generic migration patterns. The proposed approach has been implemented in a software tool that provides useful functionalities for protocol managers.

ACM Transactions on The Web, 2008

In Service-Oriented Architectures, everything is a service and everyone is a service provider. Web services (or simply services) are loosely coupled software components that are published, discovered, and invoked across the Web. As the use of Web services grows, in order to correctly interact with the growing services, it is important to understand the business protocols that provide clients with the information on how to interact with services. In dynamic Web services environments, service providers need to constantly adapt their business protocols for reflecting the restrictions and requirements proposed by new applications, new business strategies, and new laws, or for fixing problems found in the protocol definition. However, the effective management of such a protocol evolution raises critical problems: one of the most critical issues is how to handle instances running under the old protocol when it has been changed. Simple solutions, such as aborting them or allowing them to continue to run according to the old protocol, can be considered, but they are inapplicable for many reasons (e.g., the loss of work already done and the critical nature of work). In this paper, we present a framework that supports service managers in managing the business protocol evolution by providing several features, such as a variety of protocol change impact analyses automatically determining which ongoing instances can be migrated to the new version of protocol, and data mining techniques inferring interaction patterns used for classifying ongoing instances migrateable to the new protocol. To support the protocol evolution process, we have also developed database-backed GUI tools on top of our existing system. The proposed approach and tools can help service managers in managing the evolution of ongoing instances when the business protocols of services with which they are interacting have changed.

Proceedings of the 3rd Asia- …, 2006

Seventh IEEE International Conference on E-Commerce Technology Workshops

Web Service protocol standards should be unambiguous and provide a complete description of the allowed behavior of the protocols' participants. Implementation of such protocols is an error-prone process, firstly because of the lack of precision and completeness of the standards, and secondly because of erroneous transformation of semantics from the specification to the final implementation. Applying the TLA+ paradigm we first consider the protocol on an abstract level. Safety properties taken from real world scenarios are compared to the facilities of the protocol. As result, we identified some limitation of applicability of the WS-BA protocol to abstract application use cases, modelled from the real world scenarios. These limitations are an omission of possible activities seen in the real world. Further, WS-C and WS-BA make assumptions about the internal structures of the participants, violating SOA paradigm. The former error could be detected by the use of formal methods. The latter can be circumvented by a sophisticated implementation strategy. The proposed strategy of implementing WS-Coordination and WS-BusinessActivity allows non-intrusive integration of the transactional framework, considering SOA requirements. This paper describes the results of analysis and some design decisions taken during the proof-of-concept implementation of WS-C and WS-BA frameworks.

Packt Publishing Ltd

2006

Bridging People and Software through Process Technology, 2005

2010 IEEE International Conference on Web Services, 2010

Recently, describing behavior of web services is becoming more and more important. This behavior can be described by business protocols representing the possible sequences of message exchanges. Since a lot of web services use access control policies to restrict the access to authorized consumers, these policies should be part of the service description. Studying the behavior of web services by analyzing their business protocol after assigning the access control policies is the main contribution of this work. Access control policies will be presented using ontology which eases policy specification and management and add some flexibility in the policy comparison. This paper introduces notions of compatibility and replaceability w.r.t. business protocols with access control policies annotations, together with the corresponding verification algorithms.