ConCon: Context-Aware Middleware for Content Sharing in Dynamic Participating Environments

In shared physical spaces such as parks, streets, tourist places etc., content generated at user´s devices tends to lose its relevance with distance from the immediate spatio-temporal neighborhood. Here, content includes sensory information as well as user generated content. In such participatory environments, content generated at the producers´ devices are often sought by applications seeking information on devices carried by consumers. Spatio-temporal context shared by producers and consumers is often a driving factor in determining the suitability of content to share in shared public spaces. In addition, mobile devices suffer from resource constraints. While there exist many middleware mechanisms to aid content sharing in participatory environments, there is need for a context-aware middleware that can provide an effective matching between consumer needs and content generated at producers under dynamically varying spatio-temporal as well as resource contexts. With this goal in mind, we propose a novel content based context-aware middleware called ConCon for dynamic participatory environments. ConCon employs a publish-subscribe architecture, with stable nodes called providers that serve as intermediaries between producers and consumers. ConCon takes into account content semantics, as well as context attributes such as location, residual energy, residual bandwidth etc. Through extensive simulation experiments performed on both real-world and synthetic traces we show that ConCon greatly enhances information quality by increasing diversity of shared content. Furthermore, ConCon reduces cost of sharing content in terms of resource usage in participatory environments.