It is in the works for the FAA, not Boeing. By the time it gets settled, who knows. Again, READ the FAA website, the latest and greatest is all right there.
Where will airspeed and all of the other variables come from? The requirements for connections to the ac GPS? What about the IRS?
Do you think that an ATC or other system built on the broadcast of the position , speed, and altitude will not have to have redundancy built in?
It will not be simple, nor should it be. It will be just like other flight systems on the ac... multiple, redundant sources.