As I understand the FAQs this is a perfectly reasonable question and yet people are still voting to close it which I'm guessing means it only has a short period of time left before it gets closed by a moderator. Is it a duplicate? If so then I'd love to see the answers but as of yet my searching hasn't turned up anything close to this. Any information would be greatly appreciated. I find it rather disconcerting how difficult it has become to ask questions on here. It seems like everyone is very trigger happy when it comes to closing questions.
I'll illustrate how the question was probably closed. Just read your own post:
It's a help-me-with-design request. Those are off-topic on StackOverflow.
This is very open-ended questions. You could pick a random protocol and give it as an answer; it was assumed that you did no research before asking.
Hmm you have actually answered your question? So what is a question then? So, it's not a real question.
Just don't do that. Titles are not for asking complete questions, but to summary them. The question itself should be clearly stated in question body. Many people are automatically closing the questions with no question mark in body or with reference to the title.
The problem is the lack of precision. You want to choose a protocol for you? It's off-topic or not constructive. You want to know how to handle authentication? Why haven't you ask about it then?
You could make from it a more clear and precise question, for example about performance problems/comparison using SOAP/JSON/raw XML services etc. But actually it's hard to say what is the core problem.
Us 3k'ers jump on 'is A better than B' type of questions - closing them as not constructive.
If you improve it, ping me and I will be glad to vote for reopening.