Publish/subscribe (pub/sub) middleware facilitates loosely coupled cooperation and fits well the needs of spontaneous, ad-hoc interaction. However, newly started mobile applications have to be bootstrapped to interpret the current flow of notifications correctly and commence normal operation. This problem is aggravated in mobile environments where disconnections and context changes occur frequently. In this paper, we propose two forms of subscriptions that allow consumers to subscribe to past events to improve the bootstrapping process. The first form uses logical mobility to harness possible client movements and subscribe in future locations to bootstrap virtual counterparts before the application needs the data. The second form is based on buffers and offers a way to integrate data repositories distributed in the network.
Mariano Cilia, Ludger Fiege, C. Haul, Andreas Zeid