The bounded shortest multicast algorithm (BSMA) is presented for const
ructing minimum-cost multicast trees with delay constraints. BSMA can
handle asymmetric link characteristics and variable delay bounds on de
stinations, specified as real values, and minimizes the total cost of
a multicast routing tree. Instead of the single-pass tree construction
approach used in most previous heuristics, the new algorithm is based
on a feasible-search optimization strategy that starts with the minim
um-delay multicast tree and monotonically decreases the cost by iterat
ive improvement of the delay-bounded multicast tree, BSMA's expected t
ime complexity is analyzed, and simulation results are provided showin
g that BSMA can achieve near-optimal cost reduction with fast executio
n.