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Timing Options
Typical Network Applications
076R155-000
SpectraComm 553 Fractional T1 DSU
D-11
Issue 7
Installation and Operation Manual
.
Figure D-7
Typical Back-To-Back Applications
SC 553
CSU/DSU
SC 553
CSU/DSU
Site A
Channel
Timing Option:
Internal Timing
Host
Computer
Timing Option:
Slave Timing
Timing Source
A. SC 553 CSU/DSU at Site A Supplies Timing
SC 553
CSU/DSU
SC 553
CSU/DSU
Site A
Channel
Timing Option:
Channel Timing
Timing Option:
Slave Timing
B. Customer Equipment at Site A Supplies Timing
Site B
Channel
Site B
Timing Source
SC 553
CSU/DSU
SC 553
CSU/DSU
Site A
Channel
Timing Option:
Timing Option:
C. Master/Slave Multiplexer Timing
Channel
Site B
Timing Source
Mux
Mux
Master
Slave
Mux Loops Timing
Back to CSU/DSU
Channel
(External/DTE Timing)
Channel Timing
(External/DTE Timing)
Channel Timing
(External/DTE Timing)