Creating a VPN-tunnel from webserver

[eluser]Unknown[/eluser]
Hello,

I've been developing a a project and document management software using codeigniter for some time now. Each project is a separate industrial air-con unit which are located all over the world.

Recently the company has started adding the pco-web-cards to the units, which allows for example error-logs to be downloaded via internet. However, a VPN-connection is obligatory to access the units directly.

For the web-software I'm developing, I would need to connect to the unit and read certain information from through the web card, but struck a wall right at the beginning. How do I create a VPN connection from a codeigniter-based web-service? I'm no expert at VPN, although I have set up a few connections, but they've always been from local desktop computers.

Thank very muc in advance

Juho / Finland