Title:        BLOCKCHAIN: Buzzword/Engineering/Science? (A distributed computing point of view)

Time：      14:00, November 28 Wednesday,2018
Location:   Room 201, Math BuildingB
Lecturer： Michel RAYNAL  Full professor,Universite de Rennes 1

Abstract：
On-going discourses and debates (sometimes careful and cautious, sometimes optimistic or even very enthusiastic) consider and present “blockchains” as THE distributed computing tool which will provide us with mutual trust and safe agreement among a set of participants (some of them being possibly dishonest), liberating us from geographical and time constraints, and offering us a new trustworthy freedom dimension. Some people even clain that it is the greatest “computing science” advance since the Internet.OK, but what about it precisely (where “precisely” means “from a scientific point of view”)? Is it new? On which concepts, notions, and techniques do blockchains reply? Are there sound scientific foundations? If “yes”, which ones? Are there theoretical results which guarantee its safety? Which are its implementability limits? Etc. Adopting a historical perspective, the talk will try to (partially) answer some of these important questions. It will more specifically focus on the notion of “distributed consensus”, which is a key element when one wants to obtain mutual agreement without relying on a centralized authority.