Patent attributes
Examples herein describe systems and methods for concealing internal applications that are accessed over the internet. A user device can select a remote internal application to access using a client. The user device can send an access request to an open listening port of an access server. The access server can be a gateway and proxy to the internal application, which can reside elsewhere. The access server can open a different randomized access port for establishing the connection by proxy to the internal application. The port number for the access port can be identified in the access request at the listening port. The access server can open the access port for a short time interval. The connection can be made through the access port during that time interval. A firewall can then close the access port but maintain an established connection between the user device and the internal application.