通过互联网保护与火鸟连接的最佳方法

I have a client-server application which use a firebird server 2.5 over internet. I have met the problem of given a secure access to FB databases and as a first approch a tried to solve this problem by integrating a tunnel solution in the application (STunnel software more exactly). BUT, this approch suffer from many aspects : - this add more resource consumption (CPU, memory, threads) at both client/server side, - sotware deployment become a serious problem because STunnel software is writen as a WinNT Service, not a Dll or a Component (WinNT Service need administrator privileges for install) and my client application need to run without installation !I have a client-server application which use a