A system is disclosed that allows an entity outside of a private network to initiate communication with another entity inside the private network. A first entity inside the private network maintains a persistent connection with a second entity outside the private network, with a port identification associated with the first entity's persistent connection. A third entity outside the private network obtains the port identification and initiates communication with the first entity by sending a message to the first entity using the port identification. The first and third entities then exchange communications outside the persistent connection. In an alternate implementation, the third entity uses the port identification to send the first entity a request for establishing a connection. The request is forwarded to the first entity through the persistent connection. The first entity responds by establishing a connection with the third entity outside the persistent connection.