Walmart Requires Lettuce, Spinach Suppliers to Join Blockchain
Notice how this article never clearly states specifically <i>how</i> a block chain solves the supply chain problem, nor does it even clearly state the problem in the first place.<p>A very common response to these block chain&#x2F;supply chain stories is that &quot;a block chain is just a database.&quot;<p>But even that statement is overly optimistic.<p>A block chain is a log file. It keeps a record of a sequence of state changes. All of the tamper-resistant properties we associate with Bitcoin come, not from the log file it uses, but from the economic incentives around changing the file.<p>So the choice isn&#x27;t between a block chain and a database for these non-economically incentivized use cases such as IBM&#x27;s supply chain projects. Rather, the choice is between a block chain and a dumb log file.