2-16
Cisco ONS 15454 Reference Manual, R7.0
78-17191-01
Chapter 2 Common Control Cards
2.4 2.4.2 VT Mapping
The XCVT card works with the TCC2/TCC2P cards to maintain connections and set up cross-connects
within the node. The cross-connect cards (such as the XCVT and XC10G), installed in Slots 8 and 10,
are required to operate the ONS 15454. You can establish cross-connect (circuit) information through
CTC. The TCC2/TCC2P cards establish the proper internal cross-connect information and relay the
setup information to the XCVT card.
Caution Do not operate the ONS 15454 with only one cross-connect card. Two cross-connect cards of the same
type (two XCVT or two XC10G cards) must always be installed.
Figure 2-4 shows the cross-connect matrix.
Figure 2-4 XCVT Cross-Connect Matrix
2.4.2 VT Mapping
The VT structure is designed to transport and switch payloads below the DS-3 rate. The ONS 15454
performs VT mapping according to Telcordia GR-253-CORE standards. Table 2-14 shows the VT
numbering scheme for the ONS 15454 as it relates to the Telcordia standard.
32125
1
2
3
4
5
Input Ports Output Ports
4X
STS-12/48
8X
STS-12
8X
STS-12
4X
STS-12/48
XCVT STS-1 Cross-connect ASIC (288x288 STS-1)
VT 1.5 Cross-connect ASIC
1
2
3
4
5
6
VTXC
336 bidirectional VT 1.5 cross-connects
Table 2-14 VT Mapping
ONS 15454 VT Number Telcordia Group/VT Number
VT1 Group1/VT1
VT2 Group2/VT1
VT3 Group3/VT1
VT4 Group4/VT1
VT5 Group5/VT1
VT6 Group6/VT1
VT7 Group7/VT1
VT8 Group1/VT2