How to write a custom dialler for dial-up network connections?

I am developing a specialised system which uses a satellite phone for

internet access.

The phone itself is buggy and does strange things, and the satellite

connection is even less reliable, dropping the connection after a few

minutes on average.

I am finding that the built-in Windows dialler is not really suitable.

It doesn't properly detect that the connection has been dropped, and

gets itself confused if the connection has not been dropped but the

application is asking for data, and I sometimes get what looks like

multiple instances of the dialler, and then nothing works at all.

Also the satellite provider occassionally fails to complete the DHCP

process, so you get a useless connection (no DNS etc).

I would like to write a custom dialler, which - in the absence of data

- pings some URL say once a minute and if this fails it hangs up and

redials.

How much work is involved in this, or does such a thing exist?