We currently use Pidgin to connect to a Sametime server, however for this to work, we must be connected to a VPN (Cisco).
For 99% of us, there isn't an issue with having the Cisco VPN client installed on each machine, as we also use other resources on the VPN, however, a small number of users must be able to connect to Sametime, however not to the VPN.
As you can see from the image above, under the "current" setup, we simply have Pidgin and the Cisco VPN client installed on every machine. As part of the VPN, we must also use a Proxy which restricts the internet usage to the point where it's unproductive (split tunneling isn't possible from the server side).
I've been trying to implement the "Proposed" setup with Ubuntu, using VMWare/Virtualbox however I'm yet to get anything to work.
I have tried a combination of things, from single to dual NIC's (both NAT and Bridged), installed rinetd to try and forward the ports (1533) and I have also tried the built in port forwarding within VMWare/Virtualbox.
Pidgin supports TURN/STUN, plus SOCKS/HTTP proxies, so I'm keen to find a way that I can setup a man-in-the-middle server that will connect to the VPN and then I can configure the Pidgin clients to use the Ubuntu server as a proxy?
Has anyone ever been able to do something like this?