Bainomugisha, EngineerParidel, KooshaVallejos, JorgeBerbers, YolandeDe Meuter, Wolfgang2023-01-262023-01-262012Bainomugisha, E., Paridel, K., Vallejos, J., Berbers, Y., & De Meuter, W. (2012). Flexub: Dynamic subscriptions for publish/subscribe systems in manets. In Distributed Applications and Interoperable Systems: 12th IFIP WG 6.1 International Conference, DAIS 2012, Stockholm, Sweden, June 13-16, 2012. Proceedings 12 (pp. 132-139). Springer Berlin Heidelberg.https://link.springer.com/chapter/10.1007/978-3-642-30823-9_11https://nru.uncst.go.ug/handle/123456789/7271Current publish/subscribe systems provide very limited support to modify subscriptions dynamically. Consequently, they cannot efficiently control the flow of events between publishers and subscribers, which may lead to unnecessary network traffic. In addition, it is not possible to automatically subscribe or unsubscribe to a service depending on certain context of use. This implies for developers to manually manage subscriptions (e.g., taking care of when to cancel or re-issue a subscription), which may result in inappropriate subscription states (e.g., subscriptions that are cancelled too late). In this paper, we propose the concept of dynamic subscription mechanisms that improves the expressiveness and flexibility of subscriptions. We introduce a new dimension to a subscription that allows a subscriber to express the flow of matched events, and when a new subscription can be (re)issued. We validate our claims for improved flexibility and expressiveness by providing language abstractions and a prototype implementation of a dynamic subscription mechanism framework called Flexub that supports a variation of subscription mechanisms. When compared to existing subscription models, our experiment results show that the support for dynamic subscription mechanisms greatly reduces network traffic of events sent from publishers to the subscribers. In addition, our approach reduces the workload on the subscriber side.enPublish/Subscribe systemsSubscription mechanismsMobile ad hoc networksContext-aware systemsOther