Whats Blockchain Good For?

Readable piece that covers positives and negative cautions.  Which gets to some reasonable rules of useful application.    In PDF form.

Blockchain Technology:  What Is It Good for?  in Queue ACM.

Industry's dreams and fears for this new technology
By Scott Ruoti, Ben Kaiser, Arkady Yerukhimovich, Jeremy Clark, and Robert Cunningham

In 2008, an author using the pseudonym Satoshi Nakamoto wrote a white paper describing Bitcoin, a new decentralized cryptocurrency.8 Unlike past attempts at forming a cryptocurrency—attempts that relied on preestablished trusted entities for the system to operate correctly—Bitcoin's design runs on the open Internet, with no one in charge, while maintaining tight security. While the building blocks of Bitcoin were not novel, the composition of these properties into a single system was a meaningful contribution,9 and Bitcoin became the first cryptocurrency to achieve widespread attention.

In response to Bitcoin's success, the technology was quickly dissected to understand how it works and what is new about it. Its most innovative component has been labeled blockchain technology, a decentralized mechanism for participants to agree upon data and computation.

Technology news commonly leaves the cheery impression that blockchain technology reduces or even completely eliminates the need for trust. The use cases of such an innovation stretch the imagination. Occasionally, there is a contrarian take.12

The truth is, trust is complicated. Blockchain technology does eliminate specific, narrow reliances on trust, but it also requires new assumptions that might be better or worse for specific use cases. Thus, there are not many single-sentence talking points that will be accurate about blockchain technology's efficiency, security, cost, etc.

It is clear that this technology requires a more nuanced discussion. Business executives, government leaders, investors, and researchers frequently ask the following three questions: (1) What exactly is blockchain technology? (2) What capabilities does it provide? (3) What are good applications?

The goal of this article is to answer these questions thoroughly, provide a holistic overview of blockchain technology that separates hype from reality, and propose a useful lexicon for discussing the specifics of blockchain technology in the future. ... "