My router is assigning two of my computers the same external IP Address, can I fix that?

Question

Well basically I have had my laptop for about 7 months, I just built a new desktop and my router assigned the same exact external IP address to it as it did to my laptop. So both of these computers have the same external IP address.

They have different internal ones, so they still connect to the internet perfectly fine etc, but for example, if I want to run a Call of Duty 4 server on my old laptop, it won't work since when people try to connect it tries to connect to my desktop. Which is because they both have the same IP address.

So basically I am wondering what I can do to remedy this problem.

Answer 1

A broadband router (or modem/router) typically has a single public IP (from DHCP or PPPoE) and masquerades multiple private LAN IP's behind that using ports to keep track of which connection is which.  But it can get confused if you use the same internet game on multiple machines on the private LAN behind it.

You need to see if your ISP has multiple public IP's available.  In case of cable that might require connecting each computer to the modem using a network switch. In the case of DSL it is usually a static package with 5 usable public IP's which can all be behind a single suitable modem/router (not all consumer routers can do that).

Answer 2

OK if you can, and most purchased modem routers can you need to assign the desktop a new IP mine has a list of assignable numbers, you go into the windows control panel, go to Network conexions, right click LAN connexions, go down to Internet protocol TCP/IP and select, go to properties and  put in dot on "use following IP address"  insert the applicable info gleaned from router info, on mine, a Belkin, you insert your desired IP address 192.168.2.101 (your router is possibly giving 192.168.2.2 or similar) and then normally 255.255.255.0

and then the default 192.168.2.1 (This is the acces router IP) and that should do it. Whilst here you might like to try OpenDNS, to do this you highlite use this DNS server and then put in 208.67.222.222. and underneath 208.67.220.220

ISP's hate this it makes it difficult for them to know what you are doing.

   To test access to router before above put in the access codes, eg in IE at the HTTP place delete that and type the access number 192.168.2.1 and hit go, if you get a router page come up then that is it if not go and get all the instructions.

  (live box,some linskys, some BT 192.168.1.1)

  

Answer 3

You only have ONE IP address, it is supplied by your ISP from dhcp. ALL machines from your connection will show this address externally. It is the only way a multiple connection to the internet can work.

Answer 4

Unless you have an unusual (expensive) connection, you only have one "external" IP address - which is for your router. Your router than passes ("routes") the traffic to your internal network, on a private range (often starting 192.168.0.). Each device in your network should have a unique address in your local private range.

Most routers do this using something called Network Address Translation. This works fine for web browsing etc, but can be a problem for games. Check your router settings and CoD4 manual, especially for something that might be called "port forwarding".

Answer 5

your isp assigns the ip address on the www side of the router. the only way to get a separate ip address is a second ip from the isp.