This paper describes a data distribution algorithm suitable for copying large files to many nodes in multiple clusters in wide-area networks. It is a self-organizing algorithm that achieves pipeline transfers, fault tolerance, scalability, and an efficient route selection. It works in the presence of today's typical network restrictions such as firewalls and Network Address Translations, making it suitable in wide-area setting. Experimental results indicate our algorithm is able to automatically build a transfer route close to the optimal. Propagation of a 300MB file from one root node to over 150 nodes takes about 1.5 times as long as the best time obtained by the manually optimized transfer route.