How to connect to network beyond the local router?

[SherpaDoug]

This is probably a basic networking question, but I am new to networking.

I can address my uC (Arduino Yun) at name.local or 192.168.1.x but how do I connect to it when it is connected to a WiFi router across town or 1000 miles away? Do I use its MAC address? Just how do I do that? Simply typing the MAC into a browser doesn't work.

Google doesn't work well to ask what something is not.

 

[xenos]

Look for dynamic DNS (if you do not have static IP) and
Port forwarding

Both should be configured so you can have access from outside.

 

[horace1]

if the Arduino is connected to a WiFi router with access to the internet you can access IP addresses on the external internet

the problem occures if the machine you are attempting to access is on a local network behind a NAT (network address translation) box - the router has to be set up so that packets arriving on it external IP address are forwarded to a local machine on a local IP address (usually called port forwarding or similar)

 

[SherpaDoug]

Can I have a Yun controlled box that for example measures water temperature, and connect it to a marina's WiFi using their WiFi ssid and password. Then connect to the Yun from my home PC across town to read water temperature at the marina, all without having to configure the marina's router? I can get their password for a couple of beers, but they are not going to let me muck with their router.

In my case I actually need minimal 2-way communication so in the example I would have to be able to send a signal from my home PC to turn on a light on the Yun when fishing is expected to be good.

 

[xenos]

No you cannot do that in IPv4 (because you cannot configure NAT).

What you could do, is set the arduino check periodicaly a web page (eg on your home) and exchange information with this intermediate "server" (read new commands to execute and write data measured).
You will get data/set commands from this server.


With Ipv6 (if supported by arduino and router) it's an other procedure...

 

[horace1]

Can I have a Yun controlled box that for example measures water temperature, and connect it to a marina's WiFi using their WiFi ssid and password. Then connect to the Yun from my home PC across town to read water temperature at the marina, all without having to configure the marina's router? I can get their password for a couple of beers, but they are not going to let me muck with their router.

In my case I actually need minimal 2-way communication so in the example I would have to be able to send a signal from my home PC to turn on a light on the Yun when fishing is expected to be good.

I assume you get your home IP address and can access your home router so you could set that up to port forward to a server program on your home PC
run a client program on the Yun at the marina that connects to the server using your home IP - either sending UDP datagrams or making a TCP connection - if TCP you will have two way communication to turn on the light