A subscription point is the name that a subscriber uses to request publications from a particular set of Publication nodes. It is the property of a Publication node that differentiates that Publication node from other Publication nodes in the same message flow.
A subscriber that registers a subscription without specifying a subscription point receives publications from any unnamed Publication node in the message flow, if there is a match with the topic and filter specified by the subscriber. Subscription points are valid only if your application is emitting to an MQ pub/sub broker; they are not supported by MQTT brokers.
This behavior applies to all message flows running in all integration nodes connected in the same network, unless the local has been specified when registering the subscription.
Using subscription points
If you have more than one Publication node in a message flow, you can differentiate between them by specifying subscription points. Choose values that indicate the type of message that is routed to each Publication node.
Consider an application that publishes stock prices. The prices that are available from the first Publication node in the message flow are in dollars. This Publication node uses the default subscription point.
You can define a second path through the message flow that takes the price in dollars, and converts this using a defined conversion value, to produce the same message but with the stock price in pounds. These messages are published at a second Publication node that has its subscription point property set to Pounds.
You might have another message flow, in the same integration node or a connected integration node, that publishes stock prices in pounds on the same topic. Make sure that it uses the Pounds subscription point, and that all other message flows that publish their stock prices in dollars use the default subscription point.
Subscribers specifying the relevant topic (for example, stock) can then choose whether to receive the information in dollars or in pounds, by using the default subscription point or the Pounds subscription point when they subscribe.