Dynamic Publish/Subscribe to Meet Subscriber-Defined Delay and Bandwidth Constraints

Current distributed publish/subscribe systems assume that all participants have similar QoS requirements and equally contribute to the system’s resources. However, in many real-world applications, the message delay tolerance of individual peers may differ widely. Disseminating messages according to individual delay requirements not only allows for the satisfaction of user-specific needs but also significantly improves the utilization of the resources in a publish/subscribe system. In this paper, we propose a peer-to-peer-based approach to satisfy the individual delay requirements of subscribers in the presence of bandwidth constraints. Our approach allows subscribers to dynamically adjust the granularity of their subscriptions according to their bandwidth constraints and delay requirements. Subscribers maintain the publish/subscribe overlay in a decentralized manner by establishing connections to peers that provide messages meeting exactly their subscription granularity and complying to their delay requirements. Evaluations show that for practical workloads, the proposed system scales up to a large number of subscribers and performs robustly in a very dynamic setting.