This exposes the detailed internal state machine of this circuit segment as tracked by Cascade's proprietary signaling, going well beyond a simple up/down and including transitional states like retry (attempting to reestablish) and wcbdeact/wcbdelete (being torn down). An admin debugging a circuit that won't stabilize would watch this value cycle -- for example repeatedly landing on retry(2) instead of settling on active(6) -- to tell whether the PVC is failing to establish versus staying up successfully. For example, seeing cktVcState stuck at calling(3) for an SVC-type circuit indicates the call-setup signaling is hanging rather than either failing outright or connecting.