System for selectively intercepting and rerouting data network traffic

For use in a data communication network comprising a plurality of nodes, one or more of which provide distribution services (DS) to users to enable an originating user to distribute a message to a destination user, each DS-providing node containing a user directory, said user directory having one or more entries identifying users and the nodes which provide distribution services to those users, and a routing table, said routing table having one or more entries each identifying another DS node and the next DS node on a route to the identified node, message intercepting system in at least one of the DS-providing nodes for selectively intercepting messages, said message intercepting system comprising:

• an intervention list data structure having one or more entries, each said entry providing at least a partial
• identification of a destination DS node, at least a partial identification of one or more users, and an intervention type;
• means for receiving incoming messages and for comparing destination DS node information and user information in said incoming messages to intervention list entries;
• and
• means responsive to a match to process incoming message as a function of the contents of the associated intervention type field.