- Cisco ONS 15454 Manual

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Cisco ONS 15454 Installation and Operations Guide
November 2001
Chapter 6 Circuits and Tunnels
Creating DCC Tunnels
sufficient capacity, CTC displays a dialog box asking whether you want to create a tunnel. Before you
create the tunnel, review the existing tunnel availability, keeping in mind future bandwidth needs. In
some cases, you may want to manually route a circuit rather than create a new tunnel.
6.9 Creating DCC Tunnels
SONET provides four data communications channels (DCCs) for network element operations,
administration, maintenance, and provisioning: one on the SONET Section layer and three on the
SONET Line layer. The ONS 15454 uses the Section DCC (SDCC) for ONS 15454 management and
provisioning.
You can use the Line DCCs (LDCCs) and the SDCC (when the SDCC is not used for ONS 15454 DCC
terminations) to tunnel third-party SONET equipment across ONS 15454 networks. A DCC tunnel
end-point is defined by Slot, Port, and DCC, where DCC can be either the SDCC, Tunnel 1, Tunnel 2,
or Tunnel 3 (LDCCs). You can link an SDCC to an LDCC (Tunnel 1, Tunnel 2, or Tunnel 3), and an
LDCC to an SDCC. You can also link LDCCs to LDCCs and link SDCCs to SDCCs. To create a DCC
tunnel, you connect the tunnel end points from one ONS 15454 optical port to another.
Each ONS 15454 can support up to 32 DCC tunnel connections. Table 6-6 shows the DCC tunnels that
you can create.
Figure 6-15 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 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).
Table 6-6 DCC Tunnels
DCC
SONET
Layer
SONET
Bytes
OC-3
(all ports)
OC-12, OC-48
SDCC Section D1 - D3 Yes Yes
Tunnel 1 Line D4 - D6 No Yes
Tunnel 2 Line D7 - D9 No Yes
Tunnel 3 Line D10 - D12 No Yes