The full round trip.
In fact I was interested to know this since there appears to be an apparent contradiction in the OSG since it states the max area to be served by a ring final to be 100m2 (page151). Arranging this area in a circular fashion would give a radius of 5.6m.
Yet the max length distances given in page 42, again, if arranged in a circular fashion would yield radii of 14.3 to 9.3 m.
I know we are talking about generalities but it does difficult to know which metric to choose since the disparity if quite large
cheers
PAB