Discussing the Parent Subscriber

The TED parent subscriber is first a subscriber, and can receive distributions if they are subscribed to a channel. A parent subscriber has the additional responsibility to take the distribution and pass it along to a set of designated subscribers. In this manner, a parent subscriber acts as a relay transmitter for the distributor and relays the distribution onto other subscribers. Any subscriber can become a parent subscriber without any software change. The subscriber needs to be designated a parent only in either the distributor's routing hierarchy or in a subscriber object.

There is no parent subscriber object that is created in NDS. A subscriber acts as a parent subscriber any time it is identified in either another subscriber object (as that subscriber's parent) or as an entry, with a child subscriber, in the routing hierarchy of any distributor.

A subscriber that receives a route with the distribution that identifies that it should forward the distribution on to other subscribers activates its parent subscriber code and forwards the distribution to all the subscribers in the next level of the route. Identifying a subscriber as a parent only aids the distributor in the construction of the routing for a distribution.

Just like the distributor, a parent subscriber is responsible for sending configuration information to the end-node subscriber. When the distributor sends configuration information to the parent subscriber, it includes all configuration information for any other parent or end-node subscribers to which this parent subscriber is responsible for forwarding distributions. When this parent subscriber has a distribution for a destination subscriber (parent or end node), it bundles the configuration relevant for that destination subscriber and sends it along with the distribution. All configuration information is stored in a configuration file in the TED directory. This file is created or updated when the subscriber process exits.