Every device that connects to the internet – be it a computer, phone, or smart TV – needs a way to identify itself and communicate with other devices. This is where IP addresses come in.
What is an IP address?
An IP (Internet Protocol) address is a numerical label assigned to each device on a network. You can think of it as the digital equivalent of a street address. Just as your home address tells the post office where to deliver your mail, an IP address tells the internet where to send a packet of data. Without it, your device wouldn’t be able to request or receive any information online.
When you connect to the internet, your device is usually assigned an IP address automatically by your internet service provider or your home or office router. This address can be dynamic, meaning it changes over time, or static, meaning it stays the same. Most home users receive dynamic IP addresses, while businesses and servers often use static ones for consistency and reliability.
IP addresses can also be public or private. A public IP address is visible on the internet and is used to communicate with external networks. A private IP address is used within a local network, such as your home Wi-Fi, and is not directly accessible from the internet. Your router acts as a bridge between these two types, translating private addresses into public ones through a process called Network Address Translation (NAT).
What does an IP address look like?
IP addresses come in two versions: IPv4 and IPv6. IPv4 is the older and more widely used format that consists of four numbers separated by periods (192.168.0.1). Each of these numbers is a binary octet that can range from 0 to 255.
The IPv4 format can support around 4.3 billion unique addresses. While that’s certainly a large number, it became clear many years ago that as the internet continued to grow that number simply wouldn’t be enough. IPv6 was introduced to solve this problem; it uses a longer format with hexadecimal numbers separated by colons, allowing for a vastly larger number of unique addresses (one for every grain of sand on the planet!):
As the number of available IPv4 addresses steadily becomes exhausted, we can expect to see them replaced more and more by IPv6 going forward.
How do they work?
Think of IP addresses like home addresses in a giant digital city. Just as every house on a street needs a unique number so the mail carrier knows where to deliver letters, every device on the internet needs a unique IP address so data knows where to go. When you type a website name into your browser, it’s like writing a letter to that address. Behind the scenes, the internet looks up the exact IP address (the street number) of that site, and your computer then sends packets of information labeled with both your IP (the return address) and the destination’s IP (the recipient’s address). Routers act like postal workers, reading those labels and moving the packets along the fastest route until they arrive at the right “house.”
It’s no exaggeration to state that without IPs the internet simply couldn’t function. It would be like living in a city where no one had an address, and no one ever got any mail as a result. Understanding IP addresses isn’t just for IT professionals. It can help you troubleshoot network issues, set up devices more effectively, and gain a better appreciation for how the internet works behind the scenes.
Steve Shannon has spent his entire professional career working in tech. He is the IT Director and Lead Developer at PromoCorner, where he joined in 2018. He is, at various times, a programmer, a game designer, a digital artist, and a musician. His monthly blog "Bits & Bytes" explores the ever-evolving realm of technology as it applies to both the promotional products industry and the world at large. You can contact him with questions at steve@getmooresolutions.com.