csDs3StatIntervalUASs is a read-only PerfIntervalCount counter reporting the number of Unavailable Seconds — seconds counted once ten consecutive severely errored seconds occur, marking the circuit officially down — that this unchannelized DS3/E3 physical line has recorded in one specific past 15-minute bucket out of the rolling 96 kept for the previous 24 hours (paired with a companion ValidData flag marking whether that bucket is trustworthy). (this counter applies only to DS3, not E3) A rising count here is the operational signal that an extended DS3/E3 outage such as a cut line or a reset card is happening on that interface, which is exactly the kind of degradation a monitoring admin wants an early warning of before it causes an outage. For example, a NOC engineer scrolling back through csDs3StatIntervalUASs's 96 stored 15-minute buckets could pinpoint the exact quarter-hour a spike occurred — evidence of an extended DS3/E3 outage such as a cut line or a reset card — and line that bucket up against a known maintenance window.