The NGWDM equipment provides two supervisory modes, that is, the optical supervisory channel (OSC) mode and the electrical supervisory channel (ESC) mode. The SC2 or SC1 board is used to realize the OSC mode, and the OTU board is used to realize the ESC mode.
The data communication channel (DCC) bandwidth of the NGWDM equipment is indicated by the number of bytes among loadable 64 bytes.
The DCCs that the NGWDM equipment supports and their bandwidth values are as follows:
D1�D3 3 bytes
D4�D12 9 bytes
GCC0 3 bytes
GCC12_9 9 bytes
GCC12_18 18 bytes
Pilot tone modulated DCC no concept of bandwidth in bytes
1. The OTU board with SDH services on the WDM side supports DCC type D1�D3 but does not support D4�D12.
2. The SC2 and SC1 boards support DCC types D1�D3 and D4�D12. Normally, supervisory information can be transmitted. When ASON is enabled, D4�D12 can serve as only the physical channels for transmitting ASON protocols.
3. The OTN framed OTU board supports DCC types GCC0, GCC12_9, and GCC12_18. Where, the OTN2.5G board supports GCC0 and GCC12_9, and the OTN5G and OTN10G boards support GCC0 and GCC12_18.
The bandwidth of GCC0 is three bytes, which is the same as the bandwidth of D1�D3. GCC0 refers to the GCC0 byte in the OTUk overhead of an OTN frame.
The bandwidth of GCC12_9 is nine bytes, and GCC12_18 eighteen bytes. GCC12_9 refers to the GCC1 byte in the OTUk overhead of an OTN frame, and GCC12_18 the GCC2 byte.
4. The pilot tone modulated DCC is a special mode in which radio frequency signals and service signals are coupled. Because radio frequency signals bear supervisory signals, the pilot tone modulated DCC has no concept of bandwidth in bytes. For example, the LWX board adopts the pilot tone modulated DCC.