We show that, in the constant time and processor bound models (Fraigni
aud and Lazard, 1994), the broadcast time in the back to back d-ary tr
ee BB(d, n) (Earth, 1994) is b(BB(d, n)) = right perpendicular(d+ 3)n/
2left perpendicular. In particular, to prove this result, we propose a
n algorithm for broadcasting in BB(d, n).