Cisco Systems 15454 11.3 Cross-Connect Card Bandwidth

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Cisco ONS 15454 Reference Manual, R7.0
78-17191-01
Chapter 11 Circuits and Tunnels
11.3 11.3 Cross-Connect Card Bandwidth
Figure 11-2 BLSR Circuit Displayed on the Detailed Circuit Map
11.3 Cross-Connect Card Bandwidth
The ONS 15454 XCVT, XC10G, and XC-VXC-10G cross-connect cards perform port-to-port,
time-division multiplexing (TDM). XCVT, XC10G, and XC-VXC-10G cards perform STS, VT2
(XC-VXC-10G only), and VT1.5 multiplexing.
The STS matrix on the XCVT cross-connect card has a capacity for 288 STS terminations, and the
XC10G and XC-VXC-10G cards each have a capacity for 1152 STS terminations. Because each STS
circuit requires a minimum of two terminations, one for ingress and one for egress, the XCVT card has
a capacity for 144 STS circuits, while the XC10G and XC-VXC-10G cards have a capacity for 576 STS
circuits. However, this capacity is reduced at path protection and 1+1 nodes because three STS
terminations are required at circuit source and destination nodes and four terminations are required at
1+1 circuit pass-through nodes. path protection pass-through nodes only require two STS terminations.
The XCVT and XC10G cards perform VT1.5 multiplexing through 24 logical STS ports on the XCVT
or XC10G VT matrix, and the XC-VXC-10G card performs VT1.5 and VT2 multiplexing through 96
logical STS ports on the XC-VXC-10G VT matrix. Each logical STS port can carry 28 VT1.5s or 21
VT2s. Subsequently, the VT matrix on the XCVT or XC10G has capacity for 672 VT1.5 terminations,
or 336 VT1.5 circuits. The VT matrix on the XC-VXC-10G has capacity for 2688 VT1.5 terminations
(1344 VT1.5 bidirectional circuits) or 2016 VT2 terminations (1008 VT2 bidirectional circuits). Every
circuit requires two terminations, one for ingress and one for egress. However, this capacity is only
achievable if:
• Every STS port on the VT matrix carries 28 VT1.5s or 21 VT2s.
• The node is in a BLSR or 1+1 protection scheme.