For large scale computational grids, where the resources are distributed over areas spanning thousands of miles, achieving efficiency of collective communication operations such as broadcast becomes of paramount importance. We propose a broadcast algorithm constructed in terms of point-to-point communication operations that occur according to a topology determined using a generalization of the single source shortest path algorithm such that the point-to-point operations are ordered according to a heuristic. We show that the proposed approach is competitive with, and in some cases exceeds, the performance of the broadcast operation implemented in MPICH-G2, the most used grid-enabled implementation of MPI.