IP Address?

Is there a certain IP address to certain computers? I was experimenting and I took off the cable to my computer into the laptop but they had different IP addresses. I have a router hooked up to a modem. I kept doing this and I kept getting the same IP addresses from the same computer and on the laptop. (When I say this I mean that the laptop had the same IP address the whole time but it was different from the computers which was also the same the whole time) And is it possible that my computer and laptop both have different static IP addresses. If so, how?

Public Comments

1. Your internet connection has one computer IP. So if your computer IP gets banned that means that u cant go to that spot on your internet anymore.
2. No, there is not certian IP addres for certain computers. On any network, each network device (Computers, Printers, SANS) must have there own unique IP address. On a home network this is very easy to manage. Your router will give out the next available IP address. Chances are with only 2 devices, you will get the original IP address. It is possible that your computers have static IP addresses, and if they do they need to be unique. IP address can can thought of as a house address computer A request yahoo.com and computer B request Google.com. Both peices of data come to your router, but you are not going to send google.com and yahoo.com to both computer A and computer B, so your router will read which one request yahoo.com and send it to computer A based on its IP address. Back to the house addresses if you and I had the same house address, then you might get my mail and I might get yours.
3. It is possible they both have static address set. But more likely your router is acting as a DHCP server and giving out addresses. When the computer gets an address from DHCP it also gets a "lease time" for that address. It will try to renew this lease when half of the lease time expires. The computer will try to renew the same address it held before so that is why you are getting the same address.
4. Unless manually changed, the majority of routers come configured to use DHCP (Dynamic Host Configuration Protocol) which, to simplify, means that any computer that plugs into the router will be automatically allocated a unique ip address. You can manually assign the same ip address to your computer and laptop as long as they do not connect to the router at the same time as they will cause a conflict. Basically, all computers should really have a unique ip address to save any conflicts and only in special circumstances would you need two assign to computers the same ip. Imagine an IP address like a house address. Each address is unique so that the mail man can find where to post his letters. With two houses on the same street using the same address you would not know where to post the mail. When you assign an ip address manually to a computer, this is called a 'static' ip as it never changed. Now, if you want to assign a static ip address, do the following. This is for xp and not vista but the procedure should be almost identical for all windows systems. First, you need to know the routers ip address, subnet mask, and the range of ip addresses the router allows. This bit can get confusing, ideally all this info will be in the router if you have access to it. If not, then do this on a working system. 1. Start Menu > Run > Type 'cmd' (without quotes) then press enter. 2. In the black box, type ipconfig. 3. Make note of the ip address, subnet mask and default gateway. Then to set your ip statically on the machine of your choice. 1. Open 'control panel' 2. Open 'Network Connections' 3. Right click on the 'local area connection' and select properties. 4. Double click the heading 'Internet Protocol (tcp/ip)' 5. Put a dot in the 'Use the following ip address' box 6. Fill in the ip address you wish to use. This should be nearly identical to the ip address you got through the above procedure, however if you are using different ip addresses for each machine, you should increment only the end group number i.e. Computer: 192.168.1.10 Laptop: 192.168.1.11 Unless of course you are keeping them the same. 7. Fill in the subnet mask, although it may do this for you. 8. Fill in the default gateway 9. Fill in 'Preferred DNS Server' (in this box put the same number as the 'default gateway'. Click Okay and that should be that. There are sometimes changes you need to make in the router such as addresses reservation but I'm not gonna go into that as it's different for each router and some don't have the option. As said before, leave as dynamic (dhcp) unless you have a good reason to change.
5. Any machine in a network needs a unique address. This is normally provided by the router dhcp. Your connection has a public IP address shared by all your machines, this is allocated by your ISP through their dhcp.