Setting up a Static IP address

A typical user may want to host a local file storage server on their network. They set up FTP(S) and everything, look at their network interface for the IP address, and port forward it so that it may be accessible through the internet. One day, all of a sudden, the file server becomes inaccessible from the internet. That user starts troubleshooting; the first thing that comes to mind is “can it be accessed through the LAN?”. Apparently not, the user goes into the file server and checks his FTP settings. Everything looks good, so then what seems to be the problem? Is a static IP address needed?

The user then goes into his network adapter settings, and he notices that his LAN IP address is not the same as he originally wrote down. It had changed into something else, but why?

DHCP

DHCP stands for Dynamic Host Configuration Protocol. It has been around since the early days of computer networking. It allows for a computer to obtain an IP address and the router’s from a DHCP server. A DHCP client, which is your computer, sends a request for IP information throughout the network. A DHCP server replies and assigns you an IP address as well as a gateway to the network. In a typical home setup, the router also hosts a DHCP server. This makes it very easy to give computers an address to connect to the internet, and without any user interaction. There’s a catch: each DHCP client has a “lease time”.

When the lease time is up, that computer’s IP address is up for grabs by any new devices that enter your network. This puts any computer whose purpose is to host content for people to connect to at risk. There is a solution to this though.

Static IP address

A static IP address allows the user to define his own settings. This type of setting disables DHCP functionality of a networking adapter so that you are free to configure your network as need be. A static IP address will never be changed, and will never expire. Before configuring one, you will need to know how to access your router, and check your DHCP settings to make sure the IP address you are planning on using hasn’t already been assigned to another device on your local network.

Another solution for assigning a static ip is through “DHCP reservation”. This allows you to add a pre-defined IP address on specific devices through the use of a “MAC address” obtained from your computer’s network adapter settings. This can only be configured on a DHCP server, which is your router, and may not be available with every router on the market.

Let’s take a look at how we can configure one through our computer. On Windows, right-click on the Start Menu and go to “Network Connections”.

You will see a list of network adapters available. For this one I will be going with the “Wi-Fi” interface. Look for a adapter that is active and double-click on it to open up the status window.

Here, depending on what type of adapter you’re using, you will notice that it is successfully connected to the internet as indicated on top. The current speed of the adapter is also displayed here. On the bottom, you will see the amount of data being sent and received in the form of “Bytes”.

In order to see your IP Information, click on “Details…”

This is where you want to make a reference of your IP settings, especially the ones under “IPv4 Address” which identifies your computer on the network. “IPv4 Default Gateway” is typically your router’s IP address, you will want this as well. The “IPv4 DNS Server” setting is optional. As you can see as well, the “Physical Address” is your adapter’s MAC address and should be referenced in case you want to use DHCP reservation on your router. You can also see the “Lease Obtained” and “Lease Expires” in the middle which by default is 1 day duration.

Click “Close” and head back to the status window.

At the top is the name of your network adapter, and at the bottom are the currently enabled functions within. Nowadays, IPv4 is still most commonly used in the world. IPv6 is still catching up. In order to ensure stability, go ahead and click on the check mark right next to “Internet Protocol Version 6 (TCP/IPv6)” to disable it.

Double-click on “Internet Protocol Version 4 (TCP/IPv4)”.

You will now be configuring a static IP address. Right now it is currently set to “Obtain an IP address automatically(DHCP)” by default, click on “Use the following IP address:”. For “IP address:”, “Subnet mask”, and “Default gateway” type in the settings that you’ve noted earlier under “Network Connection Details”. Right below, we are going to select “Use the following DNS server addresses:” and type 8.8.8.8 for our “Preferred DNS server:” and 8.8.4.4 for our “Alternate DNS server:”. We will be using Google DNS servers for these to ensure better performance and quicker connections.

“Validate settings upon exit” is optional. Click “OK” and “OK” again. Your network adapter will disconnect and reconnect once more. If everything went as planned, you will see “Internet” again at the top. Your computer is now configured with a static IP address.