ATL AM2048A OM, Руководство пользователя

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ATL TELECOM USER GUIDE
AM2048A OS/OM
19
4.8.1 Standalone Section
The transmission channel can be a single optical fibre, single or multimode.
Key for following diagrams:
4.8.1.1 G.703 to G.703 Transparent Timing
In this configuration, the terminals are the source of timing. One of the connected terminals
may act as a master, the other as a slave. However, both terminals could operate
independently or pleisiochronously.
Clocks T1 and T2 are independent of one another and are transported independently through
the DSL system.
G.703
AM2048
Slave
AM2048
Master
Terminal Terminal
G.703 G.703 G.703
T1
T2
B
Clock Source
Buffer - Elastic Store
Customer
Terminal
Customer
Terminal
AM2048A AM2048A
G.703/X.21/V.35/10BaseT/USB
Single Fibre
Master Slave
4
18 ATL TELECOM USER GUIDE
AM2048A OS/OM
The AM2048 automatically restricts the maximum value of N to match the number of
transmission lines enabled and the transmission line rate selected in the
“Configuration>Master/Slave” screen.
The default value of N is 32.
Note : In a G.703 to X.21/V.35 configuration, if the G.703 interface is changed to structured
working, the maximum value of N at the X.21/V.35 interface is N = 31.
To change the user port data rate:
At the master end:
1
Configuration>User Port.
2 Set the desired value of N.
Press Enter to activate the change.
4.8 SELECTING THE CIRCUIT CONFIGURATION
The term ‘digital section’ refers to the data link between the user ports of the connected
AM2048s.
In a standalone section, the AM2048s provide the complete transmission system.
In a tandem section, the AM2048s are used to extend an existing circuit or network port.
To achieve synchronous data transfer, the master AM2048 must derive its timing from the
circuit to which it is connected.
A Point-to-Point link requires two AM2048s, one master and one slave.
A Point to Multipoint link can have up to three AM2048s, one master and two slaves.
The AM2048 at one end of the digital section is selected to be a Master (ELU), the remote
end(s) are selected to be slave(s) (NTUs).
For a tandem section, the AM2048 connected to the tandem section is configured as the master.
Please refer to the diagrams on the following pages.