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| Router to WAN Connection 33 | |
Table 15 Attributes of the synchronous/asynchronous serial interface | |||
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| Description | ||
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Attribute | Synchronous |
| Asynchronous |
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Function | DDN leased line backup |
| Modem |
| Terminal access |
| Backup |
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| Asynchronous |
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| lease line |
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| terminal access |
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Protocol | PPP |
| PPP |
| MP |
| SLIP |
| LAPB |
| MP |
| HDLC |
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| X.25 |
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| Frame Relay |
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■Synchronous/asynchronous mode
Synchronous/Asynchronous serial interface can work in either synchronous or asynchronous mode. Different signalling standards are supported in these two modes. V.35 and V.24 (RS232) support synchronous operating mode, while V.24 (RS232), support the asynchronous operating mode. The maximum transmission distance and baud rate of the signal vary with the operating mode.
Table 16 Transmission rate and distance of V.24 (RS232)/V.35 cable
V.24 (RS232) |
| V.35 |
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| Maximum |
| Maximum |
| transmission |
| transmission |
Baud rate (bps) | distance (m) | Baud rate (bps) | distance (m) |
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2400 | 60 | 2400 | 1250 |
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4800 | 60 | 4800 | 625 |
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9600 | 30 | 9600 | 312 |
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19200 | 30 | 19200 | 156 |
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38400 | 20 | 38400 | 78 |
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64000 | 20 | 56000 | 60 |
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115200 | 10 | 64000 | 50 |
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- | - | 2048000 | 30 |
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