3Com 3C13886 Installation Guide - Page 65

3Com Router Module Guide Chapter 3 Multifunctional Interface Modules Table 3-12 Baud rate and transmission distance of V.24 (RS232)/V.35 cable V.24 (RS232) V.35 Baud rate (bps) Maximum transmission Distance (m) Baud rate (bps) 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 Caution: Baud rate cannot exceed 64 kbps if V.24 cable is used and the interface operates in synchronous mode. II. Introduction to DTE and DCE Synchronous serial interfaces support both DTE and DCE operating modes. Given two directly connected devices, if one operates in the DTE mode, the other will operate in the DCE mode. The DCE device provides the synchronous clock and specifies the communicating rate. The DTE device receives the synchronous clock and communicates at the specified rate. Generally, the Router is used as a DTE device. To make sure that the device is a DTE or DCE, refer to the manual shipped with this device. In addition, the following table may also help you to identify the type of the device. Table 3-13 Typical DTE and DCE equipment Equipment type Interface type Typical equipment DTE Male PC, Router DCE Female Modem, Multiplexer, CSU/DSU 3-21