Lucent Technologies FT-2000 OC-48 - Detailed Description of Operation; General Description of Operation

Circuit Pack Descriptions
Issue 8.0 July 2002
7-27
Figure 7-9. TOHCTL (LAA26) Circuit Pack
General Description of Operation 7
The TOHCTL circuit pack terminates (a) up to eight OC-3, (b) or two OC-12 1+1
(each with an active and standby DCC), (c) or four OC-12 0x1 section overhead
channels. The OC-3/OC-12 overhead channel includes section data
communications channel bytes D1-D3. Refer to Appendix A, "A SONET
Overview," for definitions of SONET sections, lines, and paths. The TOHCTL
circuit pack also interfaces with the OHCTL (TERM) and SYSCTL circuit packs.
Detailed Description of Operation 7
Control Circuitry 7
Processor. 7Figure7-10providesanoverallblockdiagramoftheTOHCTLcircuit
pack. The processor performs protocol processing for layer 3 (network) of the
Open Systems Interconnection (OSI) 7-layer stack for the OC-3/OC-12 section
DCC. The processor also manages the overhead access local area network
(OALAN) communications with the OHCTL (TERM) and SYSCTL circuit packs.
FAULT
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LAA26
TOHCTL