I presume you mean how 'not' to get bumped from the internet if someone calls.
Some ISP's allow you to set your options so this doesn't happen. For example, AOL has a setting that tells the software not to bump you for an incoming call. It asks if you have caller ID, and what kind of connection you have, and if you would like to be reconnected if you are disconnected. It doesn't always work, but at least they have it.
But as John asked, what is your ISP and what make and model of modem are you using?
IF you don't know how to get that information, then perhaps you should do a google for the Belarc Advisor. Download it and install it. It'll tell you all that.
Also, have you tried contacting your ISP's tech suppport with this issue?
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