How to Disable DHCP and Use Static IP Addresses

Protect your wireless network from unwelcome devices

Burglar fishing for information from a businessman on a laptop

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One of the great things about home routers — wired and wireless alike — is that they generally automatically assign IP addresses to devices that try to connect to the network. Since most users don't know anything about IP addresses, subnet masks, and other details, it is both efficient and convenient to let the router take care of those details.

Potential Risks

The downside to this convenience, though, is that the router shows no discretion about which devices to assign addresses to. A wireless device that gets within range of your wireless network equipment may be able to acquire an IP address from your router. Once added to the network, the connected device can access any open network resources, including unsecured media streamers and poorly secured local files.

An Ounce of Prevention

For small networks like a home network, you can add some extra protection by turning off the DHCP, or automatic IP addressing, feature of the router and manually assigning static IP addresses.

Refer to your wireless network router or access point owner's manual for details about how to access the administration and configuration screen and disable the DHCP functionality. After you do that, you will need to configure each one of your wireless network devices with a static IP address rather than for automatically acquiring IP address information using DHCP.

To find out what your current IP address information is, you can follow these steps:

  1. Click Start followed by Run.
  2. Type command followed by Enter.
  3. Type ipconfig /all in the command prompt console and press Enter.
  4. The results displayed will tell you the device's current IP address, subnet mask, and default gateway as well as the current DNS Servers.

To reconfigure the IP address settings of a device in Windows, follow these steps:

  1. Click Start followed by Control Panel.
  2. Click Network Connections.
  3. Locate the device you want to configure.
  4. Right-click it and select Properties.
  5. Under the This connection uses the following items window, scroll to the Internet Protocol (TCP/IP) entry and click the Properties button
  6. Select the radio button next to Use the following IP address and enter the IP address, subnet mask and default gateway of your choosing (use the information extracted above as a reference)
  7. Select the radio button next to Use the following DNS server addresses and enter the DNS server IP addresses from the information extracted above

Secure the Router

Establish a strong administrator password on your wireless router. Take advantage of its built-in firewall capabilities as well. Keeping its firmware up to date is also an important factor in your overall network's security posture.

If you're still using the vulnerable WEP-based encryption and your router doesn't support the newer Wi-Fi Protected Access 2 standard, then it may be time to buy yourself a new router.