Stack Overflow has at least two different tags referring to Microsoft's Remote Desktop Protocol:
I suppose you could argue that the former refers to the protocol, while the second refers to the client or something else more general, but I don't think is is a useful distinction for a programming site. It's also not like there are so many questions on this topic that you need a finer degree of distinction. Anyone who is interested in one tag will naturally be interested in the other. And any question that requires one tag should probably have (or at least fits well with) the other tag.
Providing further justification for this synonym, the tag wiki excerpts for both of these tags are exactly the same. The rdp tag has a full tag wiki, but I think that remote-desktop should be made the "master" tag because it is more self-descriptive.