General Question on remotely connecting to a thermostat.

A very basic explanation....obviously, with a static IP address, it does not change, so if you are trying to remote into the address, the number is set.

With a dynamic IP address, the address may change each time you connect to the Internet, or at certain time intervals. Dynamic IP addresses are the normal customer access method used by most ISPs or Service Providers.

Given this, something has to keep track of the IP address. This is where the DDNS service comes into play. A DDNS service will map a services to a dynamic IP address by constantly monitoring and changing the addresses in the DNS. So when your IP changes, it updates the DNS and the domain name now points to your new IP. There are both free and pay services..and the process if fairly standard.

In both cases, the IP address will be the IP address of the router. The router needs to know what to do with the data...so you need to tell the router where to send it (to your thermostat). This is set up via port forwarding in the router. All you need to know is what the IP address of the thermostat is, and what port the thermostat is listening on (6280 from the .pdf you attached). This is set up from the router's configuration webpage, and is again a very standard thing to do.

It should be pretty much set it and forget it. You may also check with the local ISP to see if they offer static IP's. Some do, but they may charge more for it.

When a home network (an intranet) is connected to the outside world (the internet) there is a device, called a "router" by many, involved. Are you familiar with that?

This device will often include support for DDNS. For instance my device (SonicWall) supports the DDNS provider DynDNS. So when my "public" IP address changes the updated information is sent to DynDNS keeping everything in sync. It also insures that the updates occur at regular intervals as required by DynDNS.

A static IP makes things a bit simpler but will likely cost more.

Your ISP does what they normally do - they have no interaction with the DDNS provider.

Your ISP may, from time to time, change your public IP address. It's the "router" (or sometimes a small program running on a PC on your network) that notices the change and updates the information needed by the DDNS provider.

It is simplest if you have a "router" that handles the DDNS updating - so if your current "router" doesn't support DDNS then you may want to invest in one that does. If you have to run a program on a PC then that's just one more thing to worry about.

Jeff,

Technically a static IP address is best but a dynamic DNS should work just fine for you and will probably be cheaper and more painless because you won't have to spend 2 hours on the phone dealing with your ISP ;-).

There are any number of dynamic DNS services but the most well known one, rock solid reliable, with built in support in many routers is http://dyn.com/dns/. You should not need to purchase a domain name, you'll get a free domain address supplied to you by DynDys.

I have a commercial account with DynDys but I think the main issue with free accounts is that you have to log into their website every 90 days or something like that or they delete the account. So just go for their ~$20 a year package and you won't have to deal with that. It even supports several addresses so you could set it up for more than one home.

http://dyn.com/dns/dyndns-pro/

Well I use SonicWall but many people don't want to spend that much for home use. So perhaps you should contact DynDns and see if they have a list of routers that offer support.

Every major router brand I know of supports it, Linksys, Netgear, Belkin and DLink to name a few. Obviously do your due diligence, I don't know every model on the market .

Can you post a screenshot Jeff so I can see what you are referring to? The only thing you should have to do is enter a host name, then click on "your current locations IP address is" to auto-fill that field, and you should be good to go, no other IP address field to fill out. From there anything additional can be done within your router with port forwarding so that when you connect to the router via DynDys you get directed to the device you want such as the thermostat.

My guess is this is some type of system with D-Link that is automating the port forwarding aspect of it and perhaps it's asking you for the IP address of the thermostat.

You want to enter your current WAN IP address. Although this is (in your case) dynamic - they want you to enter it here to get the initial HOST record created on the DNS server.

Then you need to setup your router DDNS "client" so it keeps this IP address up to date as your WAN IP address changes.

To access a computer or device on your LAN using this HOST name you will need to setup (on your router) port forwarding. Port forwarding is what allows you to use this single HOST name to access more than one computer or device on your LAN.

Do you need clarification on how port forwarding works?

As I said you enter the WAN IP address. The only address "visible" to the outside world is you WAN address.

Port forwarding is what allows you to use that address to access the computers and devices on your LAN.

Basically the HOST name associated with your WAN IP address is what allows someone in the outside world to "find" your home network.

Then port numbers are used to determine what computer or device on your LAN to connect to.

I am not familiar with the "router" you are using so I don't know what what it is capable of in regards to port forwarding.

Let me describe how port forwarding on my "router" works.

Lets say my HOST name is FREDERICK.

Lets say I have two computers (A and B) on my LAN. On computer A I have a "private" web site just for my family. On computer B I have a "public" web site for everyone else.

So I make a "port forwarding" entriy that instructs the "router" to connect web browser connections made to FREDERICK to the web site on computer B. I make another entry that instructs the "router" to connect web browser connections made to FREDERICK:8080 to computer A.

That 8080 is the port number that allows the "router" to determine which web site to connect to. The default port number for web browsers is 80, so FREDERICK by itself is really FREDERICK:80. So requests for port 80 go to computer B, requests for port 8080 go to computer A.

Oversimplified but that's the essence.

The IP address that goes into the DynDNS page is your WAN IP address - which is not going to be a 192.168.x.x. address.

Regards setting up port forwarding on your "router" I think you are going to have to read the manual. Where it asks for a port it will only be a number. I don't know what the purpose of the application name is - does selecting something there fill in the private port number?

Going back to my example. The private port number for both web servers would be 80. The public port numbers (which must be different) can be most anything. I could use 1234 to connect to computer A and 4321 to connect to computer B. So a web browser request for computer A would be FREDERICK:1234 and for computer B would be FREDERICK:4321. The "router" looks at this public port number and determines what computer to connect to and uses the associated private port number to actually make the connection.

There should be a "status" page somewhere in your "router" that tells you what your current WAN IP address is.

Where I was using the name FREDERICK you would use whatever name you entered for the HOST name on the DYN DNS page. This name is how you access your home network from the outside world.

The name entry on the "router" port forwarding page would be a name for the computer or device you are "forwarding" to - in your case it might be "Home Thermostat" or "Living Room Thermostat" - whatever makes sense. The IP address is the LAN address of the computer or device you are "forwarding" to - in your case the IP address of your thermostat.

I have been assuming all along that your thermostat is, in fact, designed to be controlled via a web browser and thus has a tiny little web server listening for a connection on port 80 - thus 80 becomes the private port number for the port forwarding entry.

If the HOST name entered into the DYN DNS page was "MyHome" and the public port you entered (for the thermostat) on the port forwarding page was 6789 to connect to your thermostat from a web browser you would enter MyHome:6789.

What happens at this point is the web browser issues a request out on the internet for a connection to MyHome:6789. Eventually a DNS server somewhere looks up MyHome and comes up with your current WAN address (which the DYN DNS service has kept up to date) so the request now looks like xxx.xxx.xxx.xxx:6789 (where xxx.xxx.xxx.xxx is your current WAN IP address) which is sufficient to establish a connection to the WAN side of your "router". Then your "router" looks at the 6789 port number part and determines from the port forwarding entries what device (your thermostat) to forward the request to. If everything works as intended you would now have a active connection to your thermostat from the browser.

Well when I setup my DYN DNS account (a long time ago) I got to pick, from a pull down list, the part that would follow the host name I entered.

So for me it is "sml-wilt-fam.dyndns.org" where "sml-wilt-fam" is the host name I entered and ".dyndns.org" is that part I selected from the pull down list.

From the Windows command line you can enter "nslookup" which will start a command line application where you can enter in a host name and see what IP address it maps to. You can use this to verify that you have your DYN DNS service correct.

What they are allowing for is port forwarding which doesn't allow setting both public AND private port number.

Sometimes you will run into hardware that has limited port forwarding options such as only having a "public" port number - that same port number is also used to connect to the computer/application.

In this case the thermostat can listen on both the normal local port number (80) and another port number which you would use as the "public" port when setting up your port forwarding.

In your case you can leave the thermostat as is and use the 6280 as both the "private" and "public" port numbers when setting up your port forwarding OR you can use the 6280 as your "private" port number and pick a different one for your "public" port number.

I just looked over this thread and I can't help but wonder: do you know the headache you could be causing yourself?

Forwarding a port is simple enough but everything accessible to the Internet is a target for hackers and/or kids who want to prank, even if it is not on port 80. (I see random intrusion attempts on my home network daily.) I don't know what the web interface to those thermostats looks like but I would guess it's not meant to be Internet-facing.

For example, if the web interface simply let's me control your t-stat without so much as a login, you've already posted enough info here for me(or anyone else) to crank your heat to 100 in summer or 40 in winter. Even if there is a password, I'm guessing it won't be very hard to hit it with a brute force cracker and get in.

Once in, it's not just about changing your temp, a vulnerability can be used to access your LAN and all the computers on it. At that point, you might as well have unprotected WiFi because it will be just as easy to access.

The better way to do this is with a VPN at the remote location. At least VPN solutions, even basic ones, are meant to be Internet-facing. Then you can VPN into the remote and access it like it is local but without forwarding ports to the t-stat and making it internet accessible.

I guess what I'm saying is: think and understand what you are doing and the implications before you do this. I have concerns that you are just opening a big can of headache.

Dave