Public IP sender/listener

I maybe having a hard time with this one just because of all the other stuff thrown in making what I want probably more complicated then I want or because I just don't know how to really put into a proper search what I am looking for. So here is what I'm looking for and either if it's short and sweet and you wanna write the code cool if not examples I can use or build off of are just as good.

I want to run an application on a computer on my home1's network which grabs the IP (got this part already finished) Then I want whenever my application calls for it from anywhere on the internet (we will refer to this as home2) from home2 I want it to broadcast the IP of home1 to home2 so that my application knows my public IP of home1.

Isn't that a bit backwards? If home2 is able to connect to home1, then home2 already has the IP address for home1, so what is to broadcast? You certainly don't want to be publicly, and repeatedly, firing off messages to the world of the IP address of home1.

Heres an example alright not the best but I think it'll get my point across.

If you know how most remote desktop programs work you don't need the public IP you basically have a way of connecting to that computer as long as it's on a network with internet and so are you. Doesn't matter if it's changed public IP's or even private IP's it always knows it's location on the internet. I want something like that so that I can at anytime connect to my home network without having to call up and ask for them to do some stuff so I can have the public IP. I'm not creating a remote desktop application by any means but I'm making program which needs to access a file over the internet on my home1 network from anywhere I have an internet connection which is home2.

Ah. I see. Well, I'm not going to touch that one. The whole issue that I see has to do with connection security, which is something I have been able to largely ignore in the programs I write. Though, it does kind of sound like you are just talking about setting up a file server, in which case you probably don't need to write anything.

im going to be using a file server but by ip address and that ip is sadly dynamic (out of my control cause else it would be static so i dont run into this issue)

Ask your IP Provider for a static IP.

The only way for you to connect to your home IP is for you to know your home IP, for a peer-to-peer connection.

Alternatively, a piece of software on your home compute connects to a server, telling that server what it's address is. You connect to that, known, server and read your current home IP, which you can then establish a peer-to-peer connection. You still need the address of that server, though.

http://www.dyn.com/

They used to be free but it appears no more. I've used them a few times over the year. It basically runs an app on a PC on your network and continually points your IP address to their servers which tie it to your domain. They used to do free domains like mydomain.dyndns.com but now you have to register one... It's cheap and easy to do.

Basically I've realized I kinda need an in the middle network (if I keep using dynamic public ip addess) to act as a server while the two networks act like a client sending the ip from one client to the server to the client that I access the server from anywhere in the world. Or I need to switch home1 to static which I can't really do because apparently I can only do that if I upgrade to business class internet services.

No you don't, DYNDNS or some other service like it makes it so dynamic IPs can have domain names attached. I use one now (and have for years) to access my network from all over the world (mostly China). Very simple and easy to use. You just end up using a domain name instead of an IP address.

Yes but dyndns ia the middle network basically my computer reports an ip or my router if it's capable (which it is) reports my public ip to the site to use for a network and from there I can use that from my computer anywhere to access my network. which I guess if I use dyndns or that other server my router supports I wouldn't mind going that way as long as the method isn't expensive. But theres one problem...My router is the second router in on the network so will this still work?

It works for your "public IP" meaning, no matter where your router is in the network or how many it's behind the IP address that is assigned to your main connection at your address is what eventually gets assigned. How things get routed from the main router to your router and then end product/server is another story and may require some configuration in your routers...

alright well they have a free trial 14 days so I'm gonna use that and try it out and see if that works well. I'm definitely up for dyndns because it's super cheap.

Good Luck!