I have a new OSX Snow Leopard server and would like to be able to have other Macs mount drives from this server over the Internet. FTP is not good enough for sharing files because we want the files to be updated without having to re-upload them.
I need this so I can share files with my company across different locations in the US.
Also, I have a static IP from my ISP and understand all of the principles of NAT.
WebDAV is probably the way to go but it has its quirks. I wouldn't recommend AFP because almost no firewall will have port 548 open by default which could cause big issues. Also, there is are some security problems like DoS which can take your AFP down pretty easily. WebDAV (similar to iDisk) is file sharing over HTTP(s) and client needs to have just port 80/443 open to get it to work. Be careful because WebDAV doesn't offer some low level options which for example allow MS Excel file sharing between users (simultaneous writing)
On the other hand there are big issues with WebDAV on Windows, in their different versions support for WebDAV works or doesn't work and you will most likely need a third party client.
The absolutely best way is to use VPN, I would recommend Fortinet with SSL VPN but there are of course another options. PPTP is not secure enough but L2TP/IPSec/SSL VPN is the way to go.
You can share your folders via AFP (via ServerAdmin). If you have a NAT firewall, you will need to map/passthrough TCP port 548 to your OS X Server. Your Mac clients will then mount via afp://yourstaticIPfromISP.
