General communication channel
The general communication channel was defined by G.709 is an in-band side channel used to carry transmission management and signaling information within optical transport network elements.
Two types of GCC are available:
In contrast to SONET/SDH where the data communication channel has a constant data rate, GCC data rate depends on the OTN line rate. For example, GCC0 data rate in the case of OTU1 is ~333kbit/s, and for OTU2 its data rate is ~1.3 Mbit/s.
