Connecting to PC behind router

Hello all!

I have a friend who is using a router to access the internet on his broadband connection. He wants to host some games, but we can't seem to connect to his PC behind his router. Is there a way to set up his router to allow us access to his PC over the internet? He set up his router (A Linksys wireless router) with the default settings basically, except for WEP enablement.

Anyway, if you could point me to a FAQ or website, or give me some direction, it would be greatly appreciated.

 

It can be done but will leave the PC a bit less safe than if it were fully behind the router so it will be Essential for him to install a good firewall (stateful would be best) on the PC before taking the action.

And depending on exactly how his ISP operates it may be necessary for him to send updates to any gamers using his PC as a server from time to time.

- The router will have an IP address. That will be the address internet gamers will need to use. The reason for my "updates" comment above is that most ISPs do not assign a static/unchanging IP address to users. Normally if the router is left on 7x24 it will retain the same address but not always. Since his IP address will not be associated with an internet domain name (so internet DNS servers would keep track of changes) he will need to let folks know via email or something.

- The router should have two features that can be used. One is quite a bit safer than the other.
** Port Forwarding - the game will use either a single TCP port or a range of them. Simply set the router to forward any traffic to those ports to the internal IP address of his PC.
** DMZ - this pretty much means the PC is completely moved from "behind" the router and sits out in the open, so to speak.

Here is a how-to from Linksys.

The basic problem you are trying to solve is to get around the way NAT (network address translation) on the router works. In brief, the NAT feature looks at outbound packets from your friend's network. Each packet will have the internal address of the originating PC in it. NAT will store that information in it's database, modify the packet to put the router's IP in the packet header, and send it off. Any reply is checked by NAT and matched up with the internal IP of the originating PC and the packet sent to that PC.

Problem is, it only works if the "conversation" was started by a PC on your friend's network. A packet starting from outside (like a call to the game) wouldn't match anything in the NAT database so the packet would be discarded.

Port forwarding gets around this by saying to NAT, "any packet for port nnn should not be examined but simply sent to PC-A (or whichever one you specified). DMZ basically forwards packets addressed to any of the possible 64K TCP/UDP ports.

 

Hi daimeionb

You may consider what I'm going to do, not to address a router/gaming problem, but to protect my primary HD from kids.... in both instances, how do you give up some control/protection to gain/allow access.
Going to buy an inexpensive HD. Purchase a special switch (can be home made) that allows selection of which drive to use before powerup. BOTH are C:\ drives. Both have OS loaded and in your friends case games, browser and any ISP program to link in. When it's game time, powers down his box, flip the switch, power up, bypass router and wire direct to modem (could be an A/B switch for this(?) and have fun. For some additional safety could have a firewall installed or just a good image copy. My approach to allow kids on my box or in your fiiends case allow gamers in.... the safest way, cut any connection to the primary HD. When in this mode, the non-used drive has no power. Total cost of this, about $50 to $100. What it provides for my sanity, priceless.