A.Accessing G.703 64 kbit/s co-directional service signals through the DB44 interface on the DM12 board

B.Electrical signal input and output interfaces for DDN, Unframed E1 and sub-rate services

C.One DX1 board can be used with two DM12

D.Access the NX6bit/s and sub-rate service signals through the DB28 connector on the DM12 board.

A.whether the optical power of the transmit-end OA board is out of the permitted range.

B.whether the line loss compensation is out of the permitted range.

C.whether a fiber cut occurs on the main optical path.

D.whether the line loss exceeds the design end of life (EOL) value

A.TRUE

B.FALSE

A.N6GSCC

B.N3GSCC

C.N1GSCC

D.N4GSCC

A.If the receiving end detects that the H1H2 byte is all "1", the local end generates an AU-AIS alarm.

B.Since the value of the AU-PTR pointer is placed in the last 10 bits of the two bytes H1 and H2, the valid value is 0~1023.

C.The root cause of the AU pointer adjustment is that the clocks between the upstream and downstream stations are not synchronized.

D.AU-PTR refers to the location of the J0 byte.