I am simulating a peer-to-peer network which uses HTTP as an application protocol and I have some uncertainty regarding how a client knows what an HTTP response will consist of.
Let's assume that a client sends an MPD (information about a video) request to an HTTP server:
GET /video.mpd HTTP/1.1
The server replies with the MPD content and also attaches additional parameters which are NOT part of the MPD to the message body:
I'm assuming that the client knows how to interpret the MPD content since it requested it in the first place. The client will however receive additional details about its parents which are not part of the MPD.
In reality, is there a way for the client to know that it is expecting parent1ID and parent2ID parameters as well and how to interpret them? If so, how does the client determine that? If not, what can be done so that a client is able to receive additional parameters?