Decision Steps

1. Direct decision rule

• The validator marks a slot as to-commit if it observes 2𝑓 + 1 commit patterns for that slot, that is, if it accumulates 2𝑓 +1 distinct implicit certificate blocks

• The direct decision rule marks a slot as to-skip if it observes a skip pattern for that slot.

2. Indirect decision rule: if the direct decision rule fails to determine the slot, the validator resorts to the indirect decision rule to attempt to reach a decision for the slot. This rule operates in two stages. It initially searches for an anchor, which is defined as the first slot with the round number (𝑟 ′ > 𝑟 + 2) that is already marked as either undecided or to-commit

• If the anchor is marked as undecided the validator marks the slot as undecided (Figure 3d)

• If the anchor is marked as to-commit, the validator marks the slot either as to-commit if the anchor causally references a certificate pattern over the slot (figure 3e) or as to-skip in the absence of a certificate pattern (Figure 3f)