A distributed Notification Bus for constrained devices

During the last years there has been a strong research effort on the autonomic communications and self-management paradigms. This paper builds on previous work by the authors on an architecture that aims to be a complete rule-based, distributed system specially designed and implemented to enable autonomic behavior on very constrained devices, such as domestic wireless routers with resources as low as 16 MB of RAM and 4 MB of storage memory. The objective is the self-management of low-cost network deployments in remote areas, with minimal infrastructure and administrative resources. An important element of this architecture is a notification bus, that would allow to route information from producers to consumers in a flexible and efficient manner. The information relayed trough the bus ranges from network event notifications to configuration change commands, between services residing on the same node or across the network. At the same time, the network topology can change at runtime, and nodes can get disconnected from the network. This paper presents a solution for this problem, a publish-subscribe system with a very small fingerprint, which routes messages in a distributed manner. It is written in a highly portable high-level language and can be deployed on a wide spectrum of devices. Using emulation, we show that it can be used even on very small devices.