This question is not terribly technical, I’m just a little confused on the general way hbbft works.
In his first response to this question, Igor explains that PoW and PoS are separate from hbbft, which is a consensus algorithm, and that hbbft should be configured to work with one. However, this medium post seems to suggest that the raw transactions submitted by users are fed directly into the hbbft algorithm (see the step-by-step scenario towards the end). In here, there is no role for PoW, PoS, or any sybil control mechanism. So I guess I’m asking, is a separate sybil control mechanism required for hbbft to work, or not?