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Cisco ONS 15454 Reference Manual, R7.0
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Chapter 11 Circuits and Tunnels
11.5 11.5.1 Traditional DCC Tunnels
11.5.1 Traditional DCC Tunnels
In traditional DCC tunnels, you can use the three LDCCs and the SDCC (when not used for ONS 15454
DCC terminations). A traditional DCC tunnel endpoint is defined by slot, port, and DCC, where DCC
can be either the SDCC or one of the LDCCs. You can link LDCCs to LDCCs and link SDCCs to SDCCs.
You can also link an SDCC to an LDCC, and an LDCC to an SDCC. To create a DCC tunnel, you connect
the tunnel endpoints from one ONS 15454 optical port to another. Cisco recommends a maximum of
84 DCC tunnel connections for an ONS 15454. Table 11-8 shows the DCC tunnels that you can create
using different OC-N cards.
Figure 11-5 shows a DCC tunnel example. Third-party equipment is connected to OC-3 cards at
Node 1/Slot 3/Port 1 and Node 3/Slot 3/Port 1. Each ONS 15454 node is connected by OC-48 trunk
(span) cards. In the example, three tunnel connections are created, one at Node 1 (OC-3 to OC-48), one
at Node 2 (OC-48 to OC-48), and one at Node 3 (OC-48 to OC-3).
Figure 11-5 Traditional DCC Tunnel
When you create DCC tunnels, keep the following guidelines in mind:
• Each ONS 15454 can have up to 84 DCC tunnel connections.
• Each ONS 15454 can have up to 84 Section DCC terminations.
Tab le 11- 8 DC C Tu nn el s
Card DCC SONET Layer SONET Bytes
OC3 IR 4/STM1 SH 1310 DCC1 Section D1 - D3
OC3 IR/STM1 SH 1310-8; all
OC-12, OC-48, and OC-192 cards
DCC1 Section D1 - D3
DCC2 Line D4 - D6
DCC3 Line D7 - D9
DCC4 Line D10 - D12
Third party
equipment
Link 1
From (A)
Slot 3 (OC3)
Port 1, SDCC
To (B)
Slot 13 (OC48)
Port 1, Tunnel 1
Node 1
32134
Third party
equipment
Link 2
From (A)
Slot 12 (OC48)
Port 1, Tunnel 1
To (B)
Slot 13 (OC48)
Port 1, Tunnel 1
Node 2
Link 3
From (A)
Slot 12 (OC48)
Port 1, Tunnel 1
To (B)
Slot 3 (OC3)
Port 1, SDCC
Node 3