is computed over all bits of the previous frame and is placed in bits 5 and 6 of the VT1.5 line quality byte (M1). REI-LV The occurrence of an REI-LV>0 is an anomaly. REI-LV is a count of the difference between the computed line BIP-2 and the received BIP-2 in the line quality byte (M1). The count is placed in bits Traditional SONET Architectures 7 and 8 of the VT1.5 line quality (M1) in the opposite direction of transmission. SEF-LV Under study. LoF-LV Under study. RDI-LV The RDI-LV defect occurs when the presence of the RDI-LV signal in 10 contiguous frames is detected. The RDI-LV defect is terminated when no RDI-LV signal is detected in 10 contiguous frames. The RDI-LV signal is the occurrence of a 1 in bit 4 of the line quality byte (M1). Figure 3-32 provides a view of the VT1.5 superframe. Path The following primitives apply to the path level: Path BIP-8 A BIP-8 error event is an anomaly that occurs when a locally computed BIP-8 does not agree with the BIP-8 sent by the signal source. Path BIP-8 is calculated over all bits of the path overhead and payload before scrambling. The computed BIP-8 is placed in the B3 byte of the following frame before scrambling. REI-P The occurrence of an REI-P>0 is an anomaly. REI-P is the count of the difference between path BIP-8 received in B3 after unscrambling and the path BIP-8 calculated over path overhead and ROW # Figure 3-32 (Frame #) VT1.5 interface superframe format. framing VT1.5 SPE capacity 500 us COLUMN # R = Reserved for future use Chapter 3 payload of the previous frame. The count is placed in bits 1 through 4 of the path status byte G1 in the opposite direction of transmission. Loss of pointer-path (LoP-P) LoP-P is a defect that occurs when either a valid pointer is not detected in eight contiguous frames or when eight contiguous frames are detected with the new data flag (NDF) set to 1001 without a valid concatenation indicator (see ANSI T1.105). An LoP-P is terminated when either a valid pointer with a normal NDF set to 1001 or a valid concatenation indicat