Metrodata ATM CBR DSU, Руководство пользователя

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TAXI UNI PORT CONFIGURATION
103 76-02-031E
15 TAXI UNI PORT CONFIGURATION
15. 1 TAXI Physical Interface
The signal is transmitted on 62.5/125um fibre at 1300nm (multimode) with transmitters and
receivers equipped with ST connectors. The signal is transmitted at 125 Mbit/s using 4B5B
line coding per ISO DIS9314-3.
15. 2 TAXI Framing
No framing is employed with the exception that TAXI IDLE is transmitted per ANSI X3T9.5.
15. 3 TAXI PLCP Layer
No PLCP is employed. ATM cells are presented to the interface without any framing being
employed.
15. 4 TAXI ATM Layer
The cell transmission rate is 231481 cells per second.
15. 5 TAXI WAN Set-Up
There is no TAXI physical layer port configuration.
15. 6 TAXI ATM Set-Up
The configuration of the TAXI port ATM characteristics are set using the path
MAIN SET-UP / ATM SET-UP / TAXI PORT .
Figure 15.1 TAXI ATM Set-up
15 . 6. 1 Forward Idle Cells
This option allows idle cells (cells that match the idle cell mask) to be forwarded rather than
deleted.
15 . 6. 2 HEC Coset
The HEC COSET option allows the HEC to be X-ORed with 0x55 so that the idle cell HEC
is non-zero.
15 . 6. 3 Idle Cell Payload
The IDLE CELL PAYLOAD option allows special patterns to be configured in to idle cells.
Most ATM UNI devices identify idle cells from the header alone (VPI, VCI, etc set to 0) and
not the payload. Therefore to give some transmission traffic density the payload may be
configured to be non-zero. The 16 bit pattern is repeated 24 times in the cell.
TAXI PORT
Forward idle cell no
HCS coset Enabled
Idle cell payload 0000000000000000