The "extended service discovery information data" points to form types registry which doesn't appear to right. Not sure what is right here.
It would be nice if the text included at least one ext= example. The text says The 'ver' attribute is a specially-constructed string (called a "verification string") that... but the repeatedly uses the term "version string" to refer to the verification string. I suggest s/version string/verification string/g. -- Kurt
