A sledgehammer to crack a nut: why blockchain is not (always) a good idea

In this short talk, we are going to discuss two somewhat provocative claims. First, cryptocurrency, the most popular application of blockchain technology, can be implemented in a much simpler and more efficient way. Second, the permissionless setting with mutual distrust, assumed by conventional blockchain implementations, is way too pessimistic in most cases. We then show how the two observations can help in designing efficient and robust replicated services.