I have developed a desktop application that connects to a MS SQL server over a network. One of my clients wants a third party company to be able to use my desktop application but connect to the MS SQL database in my client’s office. Obviously my client could open the ports to the SQL server to make this accessible from the web, but this is a huge security issue and obviously not one I want to even recommend. Is there a way that I can make my desktop application securely communicate over the web to the SQL database?

I know probably making my application web based would be the most common answer however this would be a huge amount of development and also my client needs this relatively quickly.

Any help and advice would be appreciated.

Thanks

Simon