- - () SDII. / , VC-n. :
VC-1, VC-2 - 1 2 VC-3, VC-4 - 3 4, : + PL, - ; PL - . VC-1 VC-11 VC-12, a VC-3 VC-31 VC-32, . PL :
- PL - , VC, 9 (9 , m ); (, VC-1, 2 -1, 2 ), SDH;
- - < 9 , 1 (, 1x9 VC-4 VC-32 1x6 VC-31); .
TU-n - ( ) (=1,2,3) - SDH, : PTR+VC, :
- PTR - (TU- PTR), VC-n, TU-1 = (TU-1 PTR) + VC-1;
- TU-n, VC, : TU-1 TU-11 TU-12; TU-3 TU-31 TU-32, .
TUG-n - (=2,3), :
- TUG-2 TU-11,12,2;
- TUG-3 TU-3 TUG-2.
ETSI (1992.) .9-1 VC-3-^AU-3, -2, VC-2 (, ATM).
STM-N
, , STM-1, STM-N. STM-N, .
STM-N .9-2. () 9 270xN . , . 8000 2430xN (9*270=2430). , (-
), , 1- 9-.
.9-2. STM-N
: : RSOH 3×9×N MSO 5×9×N , AU-4 l×9×N 9×26l×N (N=1,4, 16, 64, 256).