I have centos server and installed the VPN client(cisco-vpnclient) and able to connect to the server on the other side using private address and the server on the other side pingable using the private address . The question But the other side can not connect to my server using private address such as: when the other side try to ping my server using the private ip do not get any response. is VPN client working one way ( just send the data to VPN server and do not receive the data) ?