Thursday, September 10, 2009

How To Change Your IP Address

Question: How To Change Your IP Address

With some effort, its possible to change your IP address.

Answer: The procedure depends on whether the IP address is static or dynamic and whether it's public or private.

Changing Public IP Addresses

The IP addresses you use for Internet access are controlled by Internet Service Providers (ISPs). It is not easy to change these, especially if you want to do it quickly.

Some Internet services assign you static IP addresses. To change a static IP address, you will need to contact the ISP and work with their technical support to have them assign a new one.

Most Internet services, however, use dynamic IP addresses via DHCP. The policies of ISPs dictate how to change these. If your computer is directly connected to the Internet, you can attempt to release and renew the address using ipconfig or a similar utility. Consult your ISP technical support for details. Often, you will need to disconnect your modem from the Internet for a long period of time (many hours or a few days) before the ISP will assign a different dynamic IP address.

Changing Private IP Addresses

It is easier to change private IP addresses, the ones used internally on your local network. If using static addressing, you can directly set a new IP address on the device. If using dynamic addresses supplied via a network router, you have a few options:
  • release and renew the DHCP address on the client

  • set up the router (or other DHCP server) to use a different IP address range (and update addressing on the network's other devices accordingly)

  • change one or more devices on the network from dynamic to static addressing. You can mix static and dynamic clients on the same network as long as you avoid using static IP addresses within the numeric range where the DHCP server is likely to issue its addresses.

Why Change Your IP Address?

Some people change a public IP address to avoid online bans. Web site message boards and other services sometimes block individuals by their IP address. Note that some sites block people by their user names, and changing the IP address will have no effect in this case.

Additionally, an ISP may assign you an invalid address due to some technical glitch in their equipment. This is another (more legitimate) reason to change your public IP address.

Changing a private IP address does not at all help with Internet address issues. However, changing these makes sense in a few situations:

  • if you have accidentally configured an invalid address (such as a static IP address in the wrong numeric range)
  • if you are using a malfunctioning router that is providing bad addresses, such as one already being used by another computer on your network
  • if you are installing a new router and re-configuring your home network to use its default IP address range

The choice of IP address does not affect your network performance or network security in any meaningful way.