Then, I would like to try to analyze the each requirement. Another protocol besides HTTP might be considered. It is a basic system requirement and would be fulfilled no matter what profile format is introduced. I guess that profile information cache on the client side is one of the solutions. Server broadcasts a content with the name tag.
User agent look up the profile information using name tag and decides whether the content is used.
It is very simple and bandwidth saving way, but we could not change profile info dynamically. If the bandwidth requirement is critical, we could choose this way. Therefore if the default profile information list is preinstalled, a server broadcast only the changes of the default profile information when the update happens. I think we can add multiple name tags to one content in the same manner as described above. It requires the separation of profile information and content.