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Technology / How to change IP Address of my computer?
« on: 21/02/2011 14:39:11 »
If you're talking about your IP address as seen by the outside world, then you have very limited control over it. If your computer is connected directly to your ISP via a simple modem, then the IP address of your computer will be whatever your ISP assigns when you connect.
Most residential packages use dynamic assignment by default, which means that each time your modem connects you will be assigned a free IP address from a pool, and that will remain your IP address until the connection is broken for whatever reason. The address will almost certainly be different each time a connection is established, but will always be within one or more specific ranges of addresses which are used by your particular ISP.
You can request a static IP address, meaning that your IP address will always be the same, but it will still be whatever your ISP assigns to you from its own available pool of addresses (your ISP will also quite likely charge an additional fee for a static address). You can't choose any address you like, because your ISP can assign to you only addresses over which it has control itself.
If your computer is connected behind a router with NAT, then all of the foregoing applies equally to the address which the router will get from your ISP which is how your computer will appear to the outside world.
On your local area network, however, you can configure your router to use a specific IP address range, and assign static addresses to specific computers within that LAN. The three main classes of reserved addresses are:
10.0.0.0/8 (i.e. 10.0.0.0 - 10.255.255.255)
172.16.0.0/12 (i.e. 172.16.0.0 - 172.31.255.255)
192.168.0.0/16 (i.e. 192.168.0.0 - 192.168.255.255)
You can configure your router to use a subnet within any of those ranges, and then make a static assignment of an address within the chosen range to each computer if you wish.
It's possible to configure many routers to use any range you like for your LAN, but doing so will mean that those addresses in the outside world will then be inaccessible to you, because your router will treat them as LAN addresses and never send them outside your own side of the network. For example, if you configured your LAN to be on 87.112.79.0 with a subnet mask of 255.255.255.0 you could then set your computer to a static address anywhere within that range (87.112.79.0 - 87.112.79.255). But doing that would mean that the same range of addresses in the outside world would not be accessible. That's why there are reserved LAN address ranges.
Of course, if it's an entirely private network with no connection whatsoever to the outside world, you're free to assign the addresses however you wish, because there will be no clashes.
Most residential packages use dynamic assignment by default, which means that each time your modem connects you will be assigned a free IP address from a pool, and that will remain your IP address until the connection is broken for whatever reason. The address will almost certainly be different each time a connection is established, but will always be within one or more specific ranges of addresses which are used by your particular ISP.
You can request a static IP address, meaning that your IP address will always be the same, but it will still be whatever your ISP assigns to you from its own available pool of addresses (your ISP will also quite likely charge an additional fee for a static address). You can't choose any address you like, because your ISP can assign to you only addresses over which it has control itself.
If your computer is connected behind a router with NAT, then all of the foregoing applies equally to the address which the router will get from your ISP which is how your computer will appear to the outside world.
On your local area network, however, you can configure your router to use a specific IP address range, and assign static addresses to specific computers within that LAN. The three main classes of reserved addresses are:
10.0.0.0/8 (i.e. 10.0.0.0 - 10.255.255.255)
172.16.0.0/12 (i.e. 172.16.0.0 - 172.31.255.255)
192.168.0.0/16 (i.e. 192.168.0.0 - 192.168.255.255)
You can configure your router to use a subnet within any of those ranges, and then make a static assignment of an address within the chosen range to each computer if you wish.
It's possible to configure many routers to use any range you like for your LAN, but doing so will mean that those addresses in the outside world will then be inaccessible to you, because your router will treat them as LAN addresses and never send them outside your own side of the network. For example, if you configured your LAN to be on 87.112.79.0 with a subnet mask of 255.255.255.0 you could then set your computer to a static address anywhere within that range (87.112.79.0 - 87.112.79.255). But doing that would mean that the same range of addresses in the outside world would not be accessible. That's why there are reserved LAN address ranges.
Of course, if it's an entirely private network with no connection whatsoever to the outside world, you're free to assign the addresses however you wish, because there will be no clashes.