Minecraft co-op survival?

I wish to play minecraft survival with my friend in another country so lan is out of the question… How can just him and i play in a private world without buying a server?

Create a server. I recommend using bukkit, if you want to add many plugins/mods to your server.

1. Download craft bukkit recommended build. Https://dl.bukkit.org/downloads/craftbukkit/
2. Create a new folder on your desktop, call it "Server" or whatever you want.
3. Place the downloaded craftbukkit file into that folder.
4. Create a new text document within the folder and copy and paste the run code for your OS. Http://wiki.bukkit.org/Setting_up_a_server

5. Rename that text document to "run.bat" make sure it is a.bat file or it won't work.
6. If done correctly, run that run.bat file and it should start setting up the server and spawning the map, a command prompt would show all this, once you've done that you will just need an IP to use, I recommend using LogMeIn hamachi, great service just add your friends to a network and you can all join the IP.

https://secure.logmein.com/products/hamachi/download.aspx

Download the official Minecraft server.

https://minecraft.net/...t/download

Follow these steps to port forward (allows your friend to connect to your server)

http://www.wikihow.com/Portforward-Minecraft

Go to this and send your friend the displayed number for him to enter in the server address box.
http://www.ipchicken.com/