no router configuration?

[sspence65]

I've seen several cloud based IOT hubs that claim to require no port forwarding or port triggering configuration on the home's default router. How can I deploy 2 way communication (oh, garage door is open? click button on cell phone app to close it.) without the user needing a course in router configuration?

[mfalkvidd]

@sspence65 welcome to the MySensors community!

Are you asking this in the context of a Controller developer? If that's the case I would use either NAT traversal or UPNP if incoming connections are important.

An alternative is to let the Controller create an outbound connection (websocket, mqtt, xmpp or whatever you like) to a cloud service, which acts as a relay point between the cell phone app and the Controller.

[sspence65]

My understanding so far is like this: If a controller sends an update / heartbeat to a IOT server, instructions from the IOT server can be passed back through that session? So the user, talking to the IOT server with his cell phone, has the ability to tell the home controller to do something, without the user having to configure NAT/PAT on the router?

[sspence65]

Is there a way to do this without a cloud server? Can the cell phone app "call home" without router configuration? Maybe pair the cell phone app with the controller initially, then a VPN or some such is maintained between them. Please forgive my ignorance. I have designed networked sensors that insert data into a mysql database, and graph the results using php and json, but sending info back to the home is new for me. I am a network engineer, but trying to prevent the user from having to be.

[tbowmo]

I do believe that most of those systems, are using a service on the internet, like pubsub etc. So the phone, and the home appliance, doesn't talk directly to each other, but rather through a central node on the net.

[sspence65]

That's what I have to figure out how to do. I was thinking of using MQTT, but pushing the commands back to the home system is kicking my butt. I can have the home subscribe to the MQTT broker, but how often should I check? If the user says "open garage door" he wants it done now, not 5 minutes from now. I can't assume I can open a IGP / UPnP port on his router.

[gohan]

If you use normal mqtt implementation, the communication is pretty much instantaneous; the only problem you may encounter is to keep NAT session open on the router so you need to make sure the node "pings" the mqtt broker regularly otherwise after some minutes without traffic routers will close the NAT session and traffic from the outside will not get through and reach your node