This article explains the basics of network addressing, how it works, and aims to answer the following questions:

  1. What is an IP Address and how do i find my IP Address?
  2. What is a Subnet Mask?
  3. What is a Gateway?
  4. What is DNS?


What is an IP Address?

Every device on your local network and the internet has its own unique IP Address. Devices on your network use their IP Address for almost all of their communication. Some examples of this are when a device like your computer wants to share files to another computer on your network. Other examples include, sending a YouTube video from your Phone to your TV over AirPlay, Printing documents to a network printer and visiting websites on the internet. Computer A and Computer B's IP Addresses must be unique for them to be able to talk to each other. Although there are many different types of IP Address ranges you can find in home and office networking, the most commonly used IP Addresses in home and office networking are:

  • through to
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What is a Subnet Mask?

As you can see from the above IP Address ranges there is a common theme here - the first 3 sets of numbers are all the same (Each set of numbers separated by a '.' is also known as an Octet). This is defined by whats called a subnet mask. Most home networking devices use a subnet mask of The subnet mask is what defines the number of useable IP Addresses on your network. Without getting into too much detail the number "255" means that all the bits in that Octet are reserved for Networks and are unavailable for Hosts to use (Hosts also known as your client devices like computers, laptops, tvs, phones etc). If an Octet has a "0" it means that all the bits in this octet are reserved for hosts or devices to use. There are more complex subnet masks which you may see different numbers like for example, "248" indicates some bits are use for network and some bits are used for hosts. If you would like to read subnetting in more depth please checkout this link.


How can i determine my useable IP Address range?

All networks will typically start with a network address and a subnet mask. The Network Address and Subnet Mask define the useable address, along with the broadcast address. The most common network address found in home and office networks today is:

Network Address:
Broadcast Address:
Subnet Mask:
Useable IP Address Range: -

You can use this simple subnet calculator to calculate a subnet based on how many useable addresses you require.


What is a Gateway Address?

A gateway address can be any useable IP Address in the subnet range that is assigned to a border router on your network which routes traffic to other networks like the internet. In most home office environments you will typically have one gateway address which will most likely be the IP Address of your modem or internet router. Common gateway addresses on home and office networks are,,,, or


What is a DNS Address?

Domain Name System (DNS) is used to resolve hard to remember IP Addresses into easy to remember names. An example of this is when you visit in your web browser you don't have to remember our IP Address of our web server, instead you can just type our easy to remember DNS name and your DNS server will resolve this name to our IP Address of our Website. On your local network your devices can use a wide range of IP Addresses as their DNS Server IP Address. A common one is to use the IP Address of your internet modem/router as this will forward the requests on to its DNS server. Other examples are your ISP's DNS server who should have their DNS IP Addresses listed on their website, Cloudflare and Google DNS and