SONET/SDH scrambling and overhead for cHDLC follow the same rules used for POS (RFC 2615, PPP over SONET/SDH).
The two key SONET/SDH parameters are scrambling and signal-label (C2-byte). Scrambling is off by default. The default value of the C2-byte is 0xCF. These two parameters can be modified using the CLI. The other SONET overhead values (for example, j0) follow the same rules as the current POS implementation.
SONET/SDH scrambling and overhead for cHDLC is not supported on TDM satellite.