- Section overhead
In
Synchronous optical networking the section overhead consists of the Regenerator Section, Pointer mechanism, and Multiplexer section, making a total of 81 bytes, (channels) of overhead information. A total of 5.184Mb/s.Format
The Regenerator Section of the Overhead consists of the following channels:-
:A1/A2 - Frame Alignment,:J0 - Trail Trace, Path Identifier, (a customer specified string, or security),:B1 - Error monitoring, BIP-8, (Bit Interleaved Parity, using bit 8),:E1 - Engineering Order-Wire,:F1 - Maintenance, or customer specified,:D1/D2/D3 - Embedded, SDH specific, (DCCr), channels used for management by the TMN (192kB/s).
The Pointer mechanism channels:-
:H1/H2/H3 - Give the start of individual containers within the payload for easy retrieval.
The Multiplexer section channels:-
:B2 - Error monitoring, BIP-24, (Bit Interleaved Parity, using 8 bits from 3 channels),:K1/K2 - Automatic Protection Switching to back up circuits/lines,:S1 - Synchronisation Status Message, (SSM), for clock quality monitoring,:D4-D12 - Embedded, (DCCm), management (TMN), or customer specified channels, (512kB/s).:M1 - Remote Error Indication
Wikimedia Foundation. 2010.