Single Page Application (SPA) / Vaadin

Dear Vaadiners … !
We want to start a web-base project in our Company and because of the high demand of updates (Request to server) in User Interface we need to use a Single Page Application (SPA) framework.
Since I have some experience with Vaadin I rather work with it. After reading in the book of Vaadin and searching, I could not conclude, what kind of requests Vaadin send to the server ?
as an example when we setContent and we want to update just a small Panel of the UI (Current Page). Does Vaadin send a request for the whole page or a request for this portion (And consequently receiving a small porion from the Server)?


the Vaadin server side tracks changes to components, layouts etc. and only sends the changed data to the client. This keeps the amount of data sent very low (after the initial application loading of course).

You can easily examine this using the network tab of e.g. Chrome dev tools and look at the requests and responses while interacting with a Vaadin application.