1. An apparatus for controlling subscriptions, the apparatus comprising: a processor with a detector operable to detect a subscription associated with a wildcard topic string; and an analyzer, responsive to the detection of the subscription associated with the wildcard topic string and a topic string of a topic node matching the wildcard topic string, for analyzing a first attribute of the topic node, wherein the analyzer determines whether a subscriber associated with the subscription should receive a message associated with the topic string of the topic node.