How does CasperLab’s proof of stake design differ from that of Ethereum 2.0?
What Ethereum is building for Eth 2.0 - Casper FFG is a ‘finality gadget’ - it is an overlay on top of PoW. The beacon chain will use PoW to select the next tip of the chain. Miners will still have to use PoW to propose a block. Then PoS validators will use Casper FFG to ‘finalize’ that block. This will provide a mechanism that will prevent reversion - a problem in PoW.
In our protocol, no PoW exists. Validators will propose blocks according to the protocol, completely eliminating PoW. This is the hard part with CBC-Casper, as the 2017 paper did not specify how this part happens. This is the research that we completed as part of the Highway Protocol.