Quidway® NetEngine 20 Routers Synchronous Serial Port Module
Copyright ©2007 Huawei Technologies Co., Ltd. All rights reserved.
http://www.huawei.com/products/datacomm/
1
Quidway® NetEngine 20 Routers Synchronous Serial Port Module
Overview
The synchronous serial port module (4SAE) of an NE20 router implements the sending, receiving
and processing of synchronous serial port data stream. It supports data terminal equipments (DTE)
and data circuit-terminating equipments (DCE).
A synchronous serial port can work in the DTE or DCE mode. Two devices directly connected must
work respectively in the DTE and DCE modes. The DCE provides the synchronization clock and
assigns communication rate, while the DTE receives the synchronization clock and communicates
according to the assigned baud rate.
Electrical signal standards and baud rates supported by a synchronous serial port varies with the
working mode. The maximum transmission distance of signals depends on the baud rate and cable.
Refer to the table below for the mapping between cable, baud rate and the maximum transmission
distance of signals.
V.24
V.35
Baud rate
(bit/s)
Maximum transmission
distance (m)
Baud rate
(bit/s)
Maximum transmission
distance (m)
2400 60
2400
1250
4800 60
4800
625
9600 30
9600
312
19200 30
19200
156
38400 20
38400
78
64000 20
56000
60
115200 10
64000
50
- -
2048000
30
