Where does Wal-Mart’s supply chain start? What triggers Wal-Mart’s Retail Link system to ship goods to local Wal-Mart Stores?

Walmart is a well-known leader in the application of network technology to coordinate its supply chain. Walmart's supply chain is the secret sauce behind its claim of offering the lowest prices everyday. It's able to make this promise because it has possibly the most efficient B2B supply chain in the world. It doesn't hurt to also be the largest purchaser of consumer goods in the world. With sales of more than $443 billion for the fiscal year ending January 31, 2012, Walmart has been able to use information technology to achieve a decisive cost advantage over competitors. As you might imagine, the world's largest retailer also has the world's largest supply chain, with more than 60,000 suppliers worldwide. In the next five years, the company plans to expand from around 5,000 retail stores in the United States (including Sam's Clubs) to over 5,500 and increase its selection of goods. Internationally,