This article is from a FAQ concerning SCO operating systems. While some of the information may be applicable to any OS, or any Unix or Linux OS, it may be specific to SCO Xenix, Open There is lots of Linux, Mac OS X and general Unix info elsewhere on this site: Search this site is the best way to find anything.
This is an ancient post with no relevance to modern systems.
Because you need the modem speed in /etc/inittab to match the DTE rate that the modem is set for. If the DTE rate is fixed, the modem can connect with another modem at any speed. See /Unixart/hispeed.htmli for a full description of how to do this, but the overall picture is this:
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