Priority Quality Level (PQL) values allow translation of SSM values for mixed carrier (DS1 and E1) environments. The SSM to PQL translation is performed by the input when SSM signals are received. The PQL to SSM translation is performed by the DS1/E1 output when SSMs are generated.
PQLs allow the system to compare and rate signal quality from different sources and to provide an effective way to communicate the quality of output signals. Corresponding PQL numbers and SSM values for DS1 and E1 are listed below.
PQL # |
DS1 SSM |
DS1 Text Description |
E1 SSM |
E1 Text Description |
1 |
-- |
|
-- |
|
2 |
0x04 |
PRS |
0x02 |
|
3 |
0x04 |
|
0x02 |
PRC/G.811 |
4 |
0x08 |
STU |
0x00 |
STU |
5 |
0x0C |
St2 |
0x04 |
Type II |
6 |
0x78 |
Type I |
0x04 |
Type I |
7 |
-- |
Type V |
-- |
G.812 Transit |
8 |
0x7C |
St3E |
0x08 |
Type III |
9 |
0x10 |
Type VI |
0x08 |
G.812 Local |
10 |
0x10 |
St3 |
0x0B |
Type IV |
11 |
0x22 |
|
0x0B |
G.813 Opt1 |
12 |
0x22 |
SMC |
0x0F |
G.813 Opt2 |
13 |
0x28 |
St4 |
0x0F |
|
14 |
0x40 |
Reserved |
0x0F |
|
15 |
0x30 |
DUS |
0x0F |
DUS |
16 |
0x7E |
Unassigned |
0x0F |
Unassigned |