I wondered if there was an app? The best I could think of was to use certificates, but I don't have the server resources to deploy a solution like this and have it control the connections. So, can I use a plain ole XP Pro machine or would I need to set a linux server? We are nonprofit, as I am sure you have heard before.
I have to find a very minimal cost solution to deploy . I think it would be far too complicated to expect them to manage a linux server with certificate authority - not to mention that security is not my forte, but with lots of reading .... possible, LOL.
Looking forward to your ideas and comments!