I must sometimes write software to establish a socket with a particular server residing within a Cisco VPN. I simply write my software as if there were no VPN (making use of the standard sockets library). When it is time to run this program, I manually connect to the VPN using the client software installed on my computer, then run the program itself.
However, it would be desirable to write the software to take advantage of a specialized socket library capable of communicating over the VPN directly, without the use of any installed client software.
Here is some Java code illustrating the functionality I would like:
String vpnHost = ...;
String vpnUser = ...;
String vpnPassword = ...;
VPNConnection vpnConnection = new CiscoVPNConnection(vpnHost, vpnUser, vpnPassword);
String serverHost = ...;
int serverPort = ...;
Socket socket = vpnConnection.openSocket(serverHost, serverPort);
Is it possible to establish such a connection to a VPN without installing any client software?