I'm assuming your dial-up SW (or DSL software?) disconnects after a certain period of inactivity, and you'd like some utility to periodically ping some remote host to prevent the disconnect? I'm not sure of any utilities, but I'm sure you can write a DOS batch file. I'm not sure of the syntax, but the pseudo code would be
while (true)
sleep 2 minutes //pick a good time
ping remote_host
Just always have this running, and it will ping remote_host every 2 minutes (or whatever time you specify)
Hope that helps!