h1. Architecture Overview

The core concept behind Karaf Cellar is that each node can be a part of one or more groups, that provide the node distributed memory for keeping data (e.g. configuration, features information, other) and a topic which is used to exchange events with the rest group members.

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Each group comes with a configuration, which defines which events are to be broadcasted and which are not. Whenever a local change occurs to a node, the node will read the setup information of all the groups that i belongs to and broadcast the event to the groups that whiteless the specific event.

The broadcast operation is happening via the distributed topic provided by the group. For the groups that the broadcast is supported, the distributed configuration data will be updated so that nodes that join in the future can pickup the change.