As cross-connects on logical interfaces are instantiated or released, and available channel counts are respectively diminished or augmented, there is a potential for the available channel counts to cross a threshold. The threshold value may be crossed in the positive direction as the available channel count is rising, or in a negative direction as the available channel count is falling. The threshold values are described as the vsiAvailableChnlWarnThreshold and the vsiAvailableChnlAlarmThreshold objects. The vsiControllerIndex identifies the controller domain in which the threshold event took place. The vsiAvailableChnlThresholdStatus indicates the particular kind of threshold crossing that occurred. When comparison with vsiAvailableChnlWarnThreshold indicates a negative crossing, this notification, with vsiAvailableChnlThresholdStatus:warning(1) is emitted. When comparison with vsiAvailableChnlAlarmThreshold indicates a negative threshold violation, this notification, with vsiAvailableChnlThresholdStatus:alarm(2) is emitted. When comparison with vsiAvailableChnlWarnThreshold indicates a positive threshold crossing, and if the preceeding vsiLcnExhaustionNotice had been sent with the vsiAvailableChnlThresholdStatus:alarm(2) parameter, this notification, with vsiAvailableChnlThresholdStatus:recovery(3) is emitted. The agent will not generate this notification if the vsiXCTrapEnable is equal to 'false'.