While Vitalik and I haven’t agreed on all of the details of the spec, we do have consensus on many properties of the proof-of-stake protocol that will likely be implemented for the Serenity release! It is called Casper “the friendly ghost” because it is an adaptation of some of the principles of the GHOST (Greedy Heaviest-Observed Sub-Tree) protocol for proof-of-work consensus to proof-of-stake. I’ve been working on the analysis and specification of “proof-of-stake” blockchain architecture since September 2014.
