For most home computer users, to assign IP addresses across your home computer network is not usually an important concern. If you need to assign an IP to a single or a range of computers this can sound daunting; having to access your computer router and altering the settings risks changing something that will need you to perform a factory reset; but we will show you the generic settings you need. 

Some computer users will do this to secure their home computer network, others will do it to assign Network Attached Storage (NAS) drives and others will do it because they can. There are a few things that you need in order to assign an IP address on your home computer network; but be aware that this is not a method to assign a static Internet IP address with your Internet Service Provider, this must be done from your ISP and may incur a cost to whoever pays your Internet bill. 

What We Need to Assign an IP Address:

  • A Computer – connected to your router using a wired (Ethernet) connection
  • Access to Your Router – the IP address of the router, username and password will be in your manual if you have never changed this
  • The MAC address of the device or computer you want to assign an IP to

Finding Your MAC Address

Every network adapter that will have interaction on a computer network will have a MAC address and is unique to that network port. Most consumer devices will either have the MAC address printed on them or somewhere in the packaging for the product, but most computers will not and you will have to find this out by asking the computer itself. A MAC address will consist of a string of 6 pairs of digits in the format xx:xx:xx:xx:xx:xx (note that the colon : may sometimes be represented by a dash as shown on the images below ) 

Finding Your MAC on a Windows Computer

 The first thing to do is make sure that your computer is connected to a network. The reason why we do this is to make sure that the physical adapter that we retrieve an address for is the one that we actually want. If we look at the example of the laptop that I am using right now, I can find 4 different physical MAC addresses that are equally valid dependent on how I connect to the internet. If you are always using the same connection, then you will always use the same adapter, so will have the same MAC address. 

The piece of Microsoft software we are going to use is cmd.exe; so you need to go into your start menu and run the program cmd and you will find a pop up window called the Command Prompt.

Command Prompt

If your cmd has loaded like the Windows 7 version in this image then it is ready to accept your command: ipconfig /all and press return giving the information we need along with much more which we do not need to worry about. If you are going to be using the wired connection then you scroll through the information looking for something like this:

An IPconfig report on the command prompt

Here the MAC address of my Ethernet adapter is called the Physical Address and is the string of digits starting with 00-26; this is the string of digits that we need to make a note of, to assign an IP on your network.

Finding Your MAC on an OSX

If you are n Apple OSX operating system user then a similar method can be used by launching Terminal and entering the command  networksetup –listallhardwareports and the reply in Terminal will list in the format of:

  • Hardware Port: Ethernet
  • Device: en0
  • Ethernet Address: aa:bb:cc:dd:ee:ff

Finding Your MAC on Linux

Finding your MAC on a Linux machine is more difficult because the open source nature of the software means that you have many variants available. The most important thing is that you need access to a command shell. If you are using Ubuntu then this is called Xterm but depending on the Linux build it could be called Terminal or Command Prompt or any other variant on the theme.

Once inside your chosen “terminal” program you should ask input the command su –c “/sbin/ifconfig”  and if prompted enter your root user password. Like the Windows and OSX examples, the output in your terminal client will be laid out in a way that you can find the adapter you need. Ethernet (wired) connections generally use the prefix eth for their hardware.

Setting a Static IP on Your Router       

Once you have your MAC address you can use this to give a static IP on your router software. Your routers manual will usually tell you how to reach the support software inside, but when you start a web browser you need to input an IP address to get access to the router; some of the common ones are:

  • : 3Com, ASUS, D-Link, Dell, Linksys, Telnet
  • : Ambit
  • : D-Link, Linksys, Netgear

You will be asked for the username and password. If you have never changed these before then they will be in your manual, or a quick online search of your routers make and model will tell you. If you have never changed your default access for your router do it, do it now, do it, do it. Think about it this way; if you leave your network access on default passwords, people can let themselves into your computer network and Internet connection and download anything legal or otherwise.

The most important thing to look for is a reference to setting static local IPs. This can often be found within the settings menu for DHCP (Dynamic Host Configuration Protocol) but will need you to look for it as every router can be different. In this example we are going to be using a TP-Link TL-WR1043ND Ultimate Wireless N Gigabit Router - if anyone is looking for a budget Gigabit router I recommend it more than a Belkin!

DHCP Basics on the TP-Link

DHCP Settings on a TP Link RouterI have already logged in on this router and have gone to the DHCP Settings menu. The image to the right is the screen that appears as default and shows (from the top down):

  • Option to turn off on on the DHCP settings - You must have a DHCP Server switched on in your network, or you must assign all the local IP addresses manually
  • The address range which is available for use - the defaults are usually enough
  • The IP address lease time - Not relevant to the task in hand (unless you have in excess of 100 devices accessing your router)
  • Default Gateway - The IP address of the router (what you usually use to reach your router settings page)
  • Default Domain / Primary DNS / Secondary DNS - Not relevant to the task in hand

Can You See Your Device?

DHCP Client ListSome routers come with an option to check what devices are actively connected to the router and their IP addresses. The router we are using offers this so we can see that there are 4 devices connected.

This is useful if you want to double check your MAC address, not all routers will offer easy to remember names like this one which is why I have not recommended this method of finding it in the first place.

Reserving An IP Address

Address ReservationTo reserve your IP address you usually need your MAC address and a chosen IP address.  Plug both into the address reservation screen and save the amendment.

This will usually not actually occur until you next reboot your router and then your computer; in that order. 


Your IP Address is now Static

The benefits of making devices static on your local home network could now be obvious. Use VNC clients to control computers? Have a DIY electronic surveillance system? Thinking of ways to re-use your old computer? Many new projects are made easier with computers that are have static local IP addresses; now yours does too.