When to Use a Static IP Address

A static IP address, or fixed IP address, is an IP address that never changes. Not everyone needs a static IP address, but knowing how they differ from dynamic IP addresses can help you understand whether you should use a static IP address.

Static IP Address Uses

Here are some example situations for when you might need a static IP address:

• Setting up a home file server.
• Adding a second router to a network.
• Enabling access to a computer when away from home or work.
• Forwarding ports to certain devices.
• Sharing a printer over a network.
• Connecting to an IP camera when away from home.

Static & Dynamic: What They Mean

The terms static and dynamic are simple to understand. At the core, the only real change you'll notice between static versus dynamic IP addresses is that the former never changes, while the latter does.

Most people don't care if their IP address changes. If you never know what your IP address is and never have a reason to keep it the same, then dynamic addresses are fine for you.

However, if your network or computer is set up in a specific way where some devices would work easier and set up would be smoother for you as the admin if an IP address always stayed the same, then static addressing is what you want.

Static IP addresses are assigned manually by an administrator. In other words, the device receiving the static IP is given a specific address (such as 192.168.1.2), and from then on, the address never changes.

Dynamic IP addresses are not assigned manually. They are assigned automatically by DHCP (Dynamic Host Configuration Protocol).

When Static IP Addresses Are Used

Static IP addresses are necessary for devices that need constant access.

For example, a static IP address is necessary if your computer is configured as a server, such as an FTP server or web server. If you want to ensure that people can always access your computer to download files, force the computer to use a static, never-changing IP address.

If the server was assigned a dynamic IP address, it would change occasionally, preventing your router from knowing which computer on the network is the server.

If you want to access your home computer while you're on a trip or your work computer when you're at home, setting up the computer to use a static IP address lets you reach that computer at any time without fearing that the address will change and block your access to it.

A shared printer is another example of when to use a static IP address. If you have a printer that everyone in your house or office needs to share, give it an IP address that won't change no matter what. That way, when every computer is set up to connect to that printer, those connections remain indefinitely because the address never changes.

Here are some other reasons to use static IPs:

• They provide slightly better protection against network security problems than DHCP address assignment provides.
• Some network devices don't support DHCP.
• They help avoid potential IP address conflicts where DHCP might supply an address already assigned elsewhere.
• They provide geolocation that's more accurate than a dynamic IP address.

When Not to Use a Static IP Address

Because a static IP address is assigned manually, it's less efficient for a network admin to give it out, especially in mobile situations. Someone must visit the device in person to give it an IP address instead of letting DHCP assign the address automatically.

For example, you wouldn't set a static IP address on a smartphone because the moment it reaches another Wi-Fi network, the address might not be supported on that network, meaning that it won't be able to access the internet.

Dynamic addressing is more convenient in this situation because it's easy for administrators to set up. DHCP works automatically with minimal intervention needed, allowing mobile devices to move between different networks seamlessly.

Static IP Address Assignment on Home Networks

Businesses are more likely to use static IP addresses than home networks. Implementing static IP addresses isn't easy and frequently requires a knowledgeable technician.

However, you can have a static IP address for your home network. When making static IP assignments for local devices on home and other private networks, the address numbers should be chosen from the private IP address ranges defined by the Internet Protocol standard:

• 10.0.0.0–10.255.255.255
• 172.16.0.0–172.31.255.255
• 192.168.0.0–192.168.255.255

These ranges support thousands of IP addresses. It's common for people to assume they can choose any number in the range and that the specific choice doesn't matter much. This is untrue.

To choose and set specific static IP addresses suitable for your network, follow these guidelines:

• Do not choose any addresses that end with .0 or .255. These addresses are usually reserved for use by network protocols.
• Do not choose the addresses at the beginning of a private range. Addresses like 10.0.0.1, 192.168.0.1, and 192.168.0.100 are commonly used by network routers and other consumer devices. These are the first addresses hackers attack when trying to break into a private computer network.
• Don't choose an IP address that falls outside the range of your local network. For example, to support all addresses in the 10.x.x.x private range, the subnet mask on all devices must be set to 255.0.0.0. If they aren't, some static IP addresses in this range don't work.

How to Get a Static Public IP Address

Internet service providers (ISP) traditionally assign all their IP addresses to customers dynamically, due to historical shortages of available IP numbers.

Contact your service provider if you prefer a static IP address. You can't get a static public IP address without requesting it from your ISP. Customers can sometimes obtain a static IP by subscribing to a special service plan and paying extra fees.