Thinking Differently About Messaging

Cross-posting from my RTI blog:

Message-centric design and data-centric design are similar, but they also differ in important ways. Let’s start with some terminology. There’s a reason why DDS says “sample” where JMS says “message”: those words are intended to suggest a different mental model to you.

When you hear the word “sample,” imagine some data value (perhaps the temperature in a certain place) being published periodically. Those values describe a single logical data object — an “instance” in DDS terms — whose state changes over time. Or think of subsequent frames of a movie: the movie is a single logical object, and you view slices of it one after another. In other words, in a data-centric design, as the system’s state changes, it uses the middleware to publish that state directly.

Read the whole post here.