Cross-Connect Card Bandwidth; Dcc Tunnels; Traditional Dcc Tunnels; Table 7-5 Dcc Tunnels - Cisco ONS 15600 Reference Manual

Chapter 7 Circuits and Tunnels

7.3 Cross-Connect Card Bandwidth

The single shelf cross-connect card (SSXC) performs port-to-port time-division multiplexing (TDM).
The VC matrix has the capacity for 2048 VC4 and/or 6144 VC3 terminations. Because each VC4/VC3
circuit requires a minimum of two terminations, one for ingress and one for egress, the SSXC has a
capacity for 1024 VC4 and 3072 VC3 circuits respectively. However, this capacity is reduced at SNCP
and 1+1 nodes because three VC4/VC3 terminations are required at circuit source and destination nodes
and four terminations are required at 1+1 circuit pass-through nodes. SNCP pass-through nodes only
require two VC4/VC3 terminations.

7.4 DCC Tunnels

SDH provides four data communications channels (DCCs) for network element operations,
administration, maintenance, and provisioning (OAM&P): one on the SDH Section layer (DCC1) and
three on the SDH Line layer (DCC2, DCC3, DCC4). The ONS 15600 SDH uses the regenerator-section
DCC (RS-DCC) for ONS 15600 SDH management and provisioning. An RS-DCC and multiplex-section
(MS-DCC) each provide 192 Kbps of bandwidth per channel. The aggregate bandwidth of the three
MS-DCCs is 576 Kbps. You can tunnel third-party SDH equipment across ONS 15600 SDH networks
using one of two tunneling methods, a traditional DCC tunnel or an IP-encapsulated tunnel.

7.4.1 Traditional DCC Tunnels

In traditional DCC tunnels, you can use the three MS-DCCs and the RS-DCC (when not used for
ONS 15600 SDH DCC terminations). A DCC tunnel endpoint is defined by slot, port, and DCC, where
DCC can be either the RS-DCC or one of the MS-DCCs. You can link MS-DCCs to MS-DCCs and link
RS-DCCs to RS-DCCs. You can also link an RS-DCC to an MS-DCC and an MS-DCC to an RS-DCC.
To create a DCC tunnel, connect the tunnel endpoints from one ONS 15600 SDH optical port to another.
Table 7-5
Table 7-5
DCC
DCC1
DCC2
DCC3
DCC4
When you create DCC tunnels, keep the following guidelines in mind:
•
•
•
•
78-18400-01
lists the DCC tunnels that you can create.

DCC Tunnels

SDH Layer SDH Bytes
RS-DCC D1 to D3
MS-DCC D4 to D6
MS-DCC D7 to D9
MS-DCC D10 to D12
Each ONS 15600 SDH can have up to 64 DCC tunnel connections.
An RS-DCC that is terminated cannot be used as a DCC tunnel endpoint.
An RS-DCC that is used as an DCC tunnel endpoint cannot be terminated.
All DCC tunnel connections are bidirectional.

7.3 Cross-Connect Card Bandwidth

Cisco ONS 15600 SDH Reference Manual, Release 9.0
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