Are messages sent once over a network or once per subscriber?
I'm looking for a general answer because this issue is going to come up all the time but here is the specific version of my question:
I have a mobile base with a stereo camera. It sends SensorData/Image over a WiFi network to a server class PC that runs two nodes that each subscribe to SensorData/Image. Is the image data sent twice across the WiFi network?
If the data is sent twice is there a built-in solution or must I write a kind of node that collects and resends these messages. In other words, insure that I have only one subscriber to each message type on the Server PC.
In general, when using a limited bandwidth network link how to make sure messages are sent only once over the link no matter the number of subscribers. Perhaps the infrastructure already takes care of this, but I don't see WHERE this could be happening.
