Figure 9: Sonet Multiplexing; Table 10: Tributary Standards That Cocx/Stmx Interfaces Support - Juniper PHYSICAL LAYER - CONFIGURATION GUIDE V11.1.X Configuration Manual

JUNOSe 11.1.x Physical Layer Configuration Guide
NOTE: To configure a whole T1 or E1 line, assign 24 T1 or 31 E1 timeslots to a
channel group or configure an unframed E1 line.
To identify a controller over SONET/SDH VT, you must consider the multiplexing for
SONET and SDH virtual tributaries. In SONET, an STS-1 frame can be divided into
seven virtual tributary (VT) groups. Similarly, for SDH, an STM-0 frame can be divided
into seven tributary units (TUs). Each group or unit contains a number of virtual
tributaries; that number depends on the VT type or TU name. Table 10 on page 114
lists the VT types and TU names that the router supports.

Table 10: Tributary Standards That cOCx/STMx Interfaces Support

Figure 9 on page 114 shows the structure for SONET, and Figure 10 on page 115 shows
the structure for SDH.

Figure 9: SONET Multiplexing

114
Platform Considerations
default channel group speed for both T1 and E1 is 64 Kbps; 56 Kbps is also
available.
An unframed E1 line
Unframed E1 lines have no timeslots reserved for framing. The router creates
one channel for an unframed E1 line and assigns the number one to that channel.
VT Type (SONET) TU Name (SDH)
VT1.5 TU-11
Not supported TU-12
Number of Tributaries
in a Group Signal Standard
4 T1
3 E1