I have a LAN in my house and it is connected to a modem/router. I have some monitoring services running in a server outside my house. I need to contact my PC from the monitoring services and send some data. The problem is that my ISP shares my public IP with other costumers. I have internet access in my LAN but i can't connect to any incoming connections inside my LAN because the ISP NAT does not map my router in any specific port. Is there a way to connect my LAN and my outside server via a VPN or something ?.