Functional Description | |
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G.703 Interface
The G.703 interface performs the following functions:
•provides a
•allocates full or fractional portion of the total 2048 kbps bandwidth to and from the G.703 interface
•frames data according to G.704
•inserts an idle code into unused time slots at the G.703 output
•recovers timing from the received G.703 signal
•monitors multiframe
•regenerates multiframe
•regenerates time slot 0 at the G.703 output
•transports time slot 16 transparently between G.703 ports
The G.703 interface operates in the structured application mode when less than 32 time slots are selected and in the unstructured mode when 32 time slots are selected (see “System Configuration” on page 25). These modes are described in detail in the “Rate Selectable Application Modes and Options” on page 14.
HDSL Interface
The HDSL interface includes the HDSL framer, which performs HDSL multiplexing and demultiplexing; a
In the transmit direction, the HDSL framer accepts inputs from the G.703 data port as shown in Figure 5. The data is placed on the HDSL pair along with the HDSL overhead bits for presentation to the transceiver. A clock representing the selected HDSL line rate is introduced to the transceiver, which outputs data on the
Reversals of Tip and Ring wires are automatically detected and accommodated. The Monitor HDSL Span screen indicates if the Tip and Ring wires are reversed.
System Timing Circuits
The UTU and ETU units can synchronize to any one of the following timing sources:
•G.703: Timing recovered from G.703 input signal
•EXT: External 2.048 MHz reference (available only for UTUs in a shelf with a management unit installed)
Processor
This device runs a program which in
•monitors the HDSL framer performance
•responds to user requests
•maintains a history of system performance
12 | August 9, 2002 |