SSL Visibility will mark an interface down and subsequently mark it's segment down when a connectivity is seen as down with an adjacent device.
SSL Visibility will mark a segment down in order to allow for fail over to a stand by system, therefore allowing recovery of the production traffic.
SSL Visibility checks for link status every 250ms and if within that time if link goes down and recovers, we will not notice it. Also, on certain platforms, in order to avoid false positive (sometimes chip is busy and not able to report link status), we check link status twice if it changed from previous state.