Modem Usage

Does your organisation use modems? Perhaps modems are used for remote diagnostics/access? Is this the most efficient cost to the organisation? How do you know that only the organisations that provide that access are dialling in? Is your network in danger from fraudulent use?
By running automatic reports that can monitor all modems within your organisation, you can identify all their traffic, the amount of time they are in use, the CLI (if provided) of the companies dialling it, etc.