Calculating E1/T1/E3/T3 Channel Sequence Numbers - HP HSR6800 Configuration Manual

Figure 8 Process of multiplexing T1 channels to form STM-1
×1
STM-1
Mapping
Aligning
Multiplexing
Figure 9 Process of multiplexing E3 channels to form STM-1
Figure 10 Process of multiplexing T3 channels to form STM-1
In actual applications, different countries and regions might adopt different multiplexing structures. To
ensure interoperability, the multiplex mode command is provided on CPOS interfaces. This allows you to
select the AU-3 or AU-4 multiplexing structure.

Calculating E1/T1/E3/T3 channel sequence numbers

Since CPOS interfaces adopt the byte interleaved multiplexing mode, the lower-order VCs are not
arranged in order in a higher-order VC. To understand how TU numbers are calculated, see the following
example where E1 channels are multiplexed to form STM- 1 through the AU-4.
×1
AUG-1 AU-4
×3
AU-3 VC-3
×3
VC-4 TUG-3
×7
×7
TUG-2 TU-11
×4
C-11 VC-11
C-11: 1.544Mbps
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