What most people do not realize about dialup modems, is that if you use analog modems for your modem pool, you will never achieve rates higher than 33.6K. So dialup directly to your network will be excrutiatingly slow.
A VPN is more secure than a dialup connection, because the authentication is typically better. Unless you are using something like SecureID on your dialup access. Again, this is probably cost prohibitive in your application.
To achieve 56K for dialup, you have to terminate the connection digitally, and use modem emulators. These devices are expensive (compared to modems). Plus, you need to either pay to have a T-1 delivered to your dialup solution, or you have to buy a digital line card for your PBX to connect to the modem pool (again, probably cost prohibitive).
The Comtrol RocketModem is 4-8 modems on a single PCI card. They use a custom ASIC to multiplex the modem signals onto the PCI bus. The driver allows you to address each of the modems on the card as if they were separate COM ports. These cards are more expensive than 4 or 8 individual modems, but you can only install one WinModem on a PCI bus, so your only alternative is to use a multi-port serial card and external modems. This is at least as expensive, and it is a real hassle to find power for the external modems, and all of the cable connections make it error prone.
If your users are only doing mail through this connection, then you may want to switch them to IMAP, rather than POP.
Also, $22 a month is a pretty expensive dialup access. There are numerous providers who setup national accounts at $10 a month, although you do have to check on the cities that they provide access in. Plus, you usually end up needing to provide Internet access for your users on the road in addition to your RAS connection, unless you will let them browse the Internet as well. At 33.6K, they won't be doing much browsing.
pansophic
