OSN8800 NG-DWDM
The DWDM equipment is provided with two clock boards TN52STG mounted in slots 42/44 of OSN8800 T32 sub-rack, which work in Active/Standby mode as depicted in Figure 8-7. These clock boards can be configured to trace a specific clock source (e.g. BITS). In OSN8800 T16 sub-rack the clock resides in cross-connect board T16XCH.
The active and standby STG/XCH boards in a sub-rack connect to all other service boards through the backplane bus to provide the following functions:
NE clock management
Synchronous clock issuing
When the standby STG detects that the active STG board is faulty or receives a switching command from the NMS, it immediately takes over the active STG board, sets itself as the active STG board, and reports a switching event. The preceding functions are not affected during the switching. There are two types of switching for the 1+1 protection switching of STGs:
Automatic switching
The STG detects its own status through hardware or software. If it is in the abnormal status, a switching is performed automatically. The switching is performed by the board and no manual operation is required. The following conditions trigger automatic switching:
A hardware fault occurs on the STG board.
The STG board goes offline when, for example, it is removed or undergoes a cold reset.
Switching occurs between the active and standby cross-connect boards in an OptiX OSN 8800 T32 sub-rack.
Manual switching
When a switching is required in a test during the normal running of the active and the standby STGs, the switching can be performed manually.
External input/output clock interfaces are provided through Synchronous Timing Interface board TN52STI mounted in slot 47 in OSN8800 T32 sub-rack. The TN52STI board obtains or outputs 2.048 MHz or 2.048 Mbit/s external clocks compliant with ITU-T G.703. The TN52STI board of an OptiX OSN 8800 device has four 120-ohm RJ45 ports: CLK1, CLK2, TOD1, and TOD2. The CLK1 and CLK2 ports are used to receive or output 2.048 MHz or 2.048 Mbit/s clock signals. Figure 8-8 illustrates how to connect the OptiX OSN 8800 T32 to a BITS device.
NOTE:
1. For OSN8800 T16 sub-rack the CLK1/CLK2 and TOD1/TOD2 ports reside on TN16ATE boards in slot 21 (ACT) and slot 22 (SBY).
2. When connecting to BITS, the NE must use the CLK1 or CLK2 port on the TN52STI board to receive or transmit external clock signals. In other words, one of the ports is used as the external clock output port and the other is used as the external clock input port. The RJ45 port on the STI board is an input and output port, but it can be used only as an input or output port in practical application.
Service Eqpt
Board
Slot
Port
Type
Remarks
OSN8800
TN52STI
47
CLK1
RJ45 120Ω
1x clock input & 1x clock output
CLK2
RJ45 120Ω
1x clock input & 1x clock output
l The TN52STI/TN16ATE board of an OptiX OSN 8800 device has four 120-ohm RJ45 ports: CLK1, CLK2, TOD1, and TOD2. The CLK1 and CLK2 ports are used to receive or output 2.048 MHz or 2.048 Mbit/s clock signals.
l The TN12STG board of an OptiX OSN 8800 universal platform subrack has two 120-ohm RJ45 (CLK and OUT) and two 75-ohm SMB ports (IN and OUT). Users can use the CLK port or the IN and OUT ports to receive and transmit 2.048 MHz or 2.048 Mbit/s clock signals. The CLK port can also be used to output 2.048 MHz or 2.048 Mbit/s clock signals.
