Connecting with a node behind a router/hub

[Phonedog911]

i have just set up a small network at my house that consists of two computers and a router(the router is connected to my cable modem). Im dont why but i can no longer connect to other computers through ip and when i look at my ip using the ipconfig command, it is different from the ip i get on a website such as www.whatismyip.com... why? i realized this because i tried to play a game of AoE with my friend and he couldnt find my game using either ip address. He has the same problem(he's behind a hub), and i couldnt connect to a game that he was hosting either. If i try to have a direct connection on AIM it fails, nobody outside my home network can even ping me. If i unplug from the router and plug directly into the cable modem, i can host games, people can ping me, etc. but then my dad doesnt have internet access...
Can anybody tell me why this happens and how i can have people connect to me while im behind this router?(and how i can connect to my friend if i he hosts the game?)

[Maestr0]

You're problem is that you are both behind NAT (Network Adress Translation) devices. A NAT device will allow multiple machines (the inside of your router which assigns local IP adresses to your computers) to share one IP adress (the outside of your router or your internet IP assinged by your ISP). Most of these routers are limted firewalls in the sense that they will not allow a connection to be initiated by anything on the external interface of the router (aka no one can connect to you from the internet unless you connect to them first). What you willl need to do is one of two things. First you can find out what ports AoE uses to communicate and forward the neccessary ports on your router to the machine on which you wish to play. If you dont want to bother with finding the ports AoE uses you can place your AoE machine in a DMZ (Demilitarized Zone) which effectively will place it outside the routers firewall and allow incoming connections. You should be able to configure your router via a web-browser check the routers manual or download the .pdf from the manufacturer.

-Maestr0

[warriorfan808]

Is your router a NAT and do your two nodes have private IP addresses? Sounds like you have private IP addresses on your nodes and if so private IP addresses aren't routable over the internet. Also, do you have your default gateways on your nodes set to the IP of your router?

[Phonedog911]

ok, cool. but, if we were actually going to connect after i turned off my router's firewall capabilites, say he was going to ping me and i had an internal network address of 192.168.0.5 and an external address of 233.346.45.31, how would he write the ip address to tell it to ping my computer on the network and not just the network itself or my dad's computer? is it like 233.346.45.31.192.168.0.5?

[extremez]

For all intents and purposes, you can't. Private IP addresses are not routable over the internet, 192.168.anything is a private address, if you try to ping it how will a public router know where to send it? THere are millions of computers with that address behind other public routers. IF you want to host a service, configure your router to forward it as maestro described in his post.

[Phonedog911]

ok, so i cant actually play AoE unless my friend and i are on the same network or one of us is directly connected to the internet and hosts the game? somebody mentioned configuring my router's firewall capabilities but i dont think it has any what exactly do you mean by forwarding the ports to the machine i wish to play on? and how do i find out what ports it uses? netstat?. if nobody is able to connect to my computer, unless i connect to them first, does that mean im totally safe from hackers and such?

[extremez]

Well if your friend has his IP directly assigned to his pc(nic) yeah do it that way, if not you need to research/netstat and find the port AoE hosts on then assign incoming traffic on that port to be forwarded to your private ip 192xxx Reading up on your router docs as well as NAT/PAT tutorials will do you good.

[Phonedog911]

thanx guys i think i understand it now.

[warriorfan808]

I"m just wondering if you can get online at all? They're right, you're going to have to publish your private IP on your router, but you should still be able to connect to the internet through your computer. That's why I was wondering if you have your default gateway setup?

If you plan on setting up through your DMZ, you might as well just install two NICS and use ICS (internet connection sharing) to share with your dad's node. I on the other hand would do what they mentioned earlier and publish your ips to your router in order for you to host. I never hosted a game, but I know I had to do that in order to get my VPN server set up.

Other than 192.168.X.X, also keep in mind that 10.X.X.X is also a range of private IPs.

I still can't figure how your friend has the same problem as you when he's using a hub. A hub wouldn't issue his node a private ip address and he should be using his public ip from his ISP.

[576869746568617]

I think maestro has the best solution. Depending on what type of NAT and /or proxy capabilities your router supports, you could simply set up a DMZ pass-through on certain TCP/UDP ports. You just set up a maping in the router to route packets that come in on router IP port x to computer IP port X.

For example, I have a router connected to a cable modem. It's IP is 207.46.245.92.
I have 2 pc's and a server. The server hosts a website and mail services (SMTP, POP3).
The server's IP is 192.168.1.1.

I want to access my mailbox as well as view my website from a friends house.

In the router, I set up a DMZ passthrough for TCP/UDP 24 (SMTP), 80 (HTTP), and 110 (POP3) to 192.168.1.1 (the server). Now I can view my website at my friend's house by typing http://207.46.245.92 because the packets are being forwarded to the server from the router. This also hides my private IP because NAT is still being performed.

Check the router's documentation and see if this feature is supported on your router. You will obviously need the port numbers of the services you plan to use. Look for them in the IANA database or E-mail the tech support for the programs you're trying to use and they will usually give these to you.

As for your friend being able to ping you across the internet, it's not giong to happen unless you set up a VPN between your router and his PC.