ADTRAN 4200659L7, 4200659L1, 4175043L2, 4200659L5, 4200659L8, 4200659L2 Alarm Description cont’d

Chapter 4. Status

Alarm	Description (cont’d)
VT-LOP	(VT Path Loss of Pointer)
	A VT LOP defect is declared when either a valid
	pointer is not detected in eight consecutive VT
	superframes, or when eight consecutive VT
	superframes are detected with the NDF set to
	“1001” without a valid concantenation indicator.
	A VT LOP failure is declared when the VT LOP
	defect persists for 2.5 +/- 0.5 seconds.
VT-AIS	(VT Path Alarm Indication Signal)
	The unit is receiving a VT path alarm indication
	signal. VT-Path AIS is specified as all ones in
	bytes V1, V2, V3, and V4, as well as all ones in
	the entire VT synchronous payload envelope. A
	VT-Path AIS failure is declared when the
	VT-Path AIS defect persists for 2.5 +/- 0.5
	seconds.
VT-RFI	(VT Path Remote Failure Indication)
	The unit is receiving a VT path remote failure
	indication. VT-RFI is declared when the
	incoming VT path remote defect indication (VT-
	RDI, “1” in bit 4 of the VT-Path Overhead byte
	(V5) in five contiguous frames) lasts for
	2.5 +/- 0.5 seconds.
VT-SLM	(VT Path Signal Label Mismatch)
	A received signal label is mismatched if it does
	not equal the locally provisioned value or the
	value “equipped non-specific”.
VT-UEQ	(VT Path Unequipped)
	The VT path is not provisioned. Byte V5 of the
	STS path overhead is set to zero.
TST	The VT/Port is in test mode.

61200659L1-1 MX2800 STS-1 User Manual 4-11