What Is an IP Address?
- An IP address uniquely identifies a device on a network. You’ve probably seen these addresses before; they look something like 192.168.1.34.
- Each IP address consists of four numbers, separated by dots (periods). Each number can range from 0 to 255.
- The full IP addressing range goes from 0.0.0.0 to 255.255.255.255.
Fun fact: Each of these numbers is actually an eight-digit binary number (sometimes called an octet). For example, the decimal number 255 in binary is 11111111.
Computers work with the binary format, but we humans find it much easier to work with the decimal format.
How Does It Work?
When you connect a device (like a computer, tablet, or phone) to a network (such as the Internet), it needs an IP address.
IP addresses allow data to be transmitted between devices. They contain location information and make devices accessible for communication.
For example, when you visit a website, your device uses its IP address to find the server where the website is hosted.
IP addresses are not random; they serve specific purposes.
Decimal vs. Binary
Remember that IP addresses are actually binary numbers.
The IP address 192.168.1.34 in binary looks like this: 11000000.10101000.00000001.00100010.
But we stick to the decimal format because it’s more human-friendly.
Why Should You Care?
Understanding IP addresses is essential for troubleshooting network issues.
If your network isn’t working correctly or a device isn’t connecting as expected, knowing about IP addressing helps.
Plus, it’s kind of fascinating!
Public IP Address:
A public IP address is an outward-facing address used to access the Internet.
It’s assigned by your Internet Service Provider (ISP) and is unique on the Internet.
Other machines and websites use your public IP to identify and communicate with devices connected to your local network.
Public IPs allow you to configure servers (like VPNs or FTP), provide remote access, and more.
However, additional security measures are needed when using a public IP to provide services online, such as using firewalls and separating public services from the LAN using a DMZ network segment1.
How to Find Your Public IP:
The easiest way is to ask Google. Navigate to www.google.com and search “what is my IP address.” Google’s first result will display your public IP.
Linux users can obtain their IP address using commands like hostname, ifconfig, or the ip command for extended capabilities1.
Public IP Ranges:
Public IP addresses belong to specific ranges, including:
1.0.0.0-9.255.255.255
11.0.0.0-100.63.255.255
100.128.0.0-126.255.255.255
Private IP Address:
Private (internal) IP addresses are not routed on the Internet.
They stay within your local network and never leave it.
No traffic can be exchanged using private IPs outside your local network.
Private IPs are assigned directly by your network router to devices within your home or office network12.
Remember, public IPs are used for online communication, while private IPs operate within local networks.
Private IP Ranges:
Class A Private IP Range:
10.0.0.0 to 10.255.255.255
These addresses are part of the class A range and are reserved for local communications within a private network
Class B Private IP Range:
172.16.0.0 to 172.31.255.255
These addresses are part of the class B range and are reserved for local communications within a private network
Class C Private IP Range:
172.16.0.0 to 172.31.255.255
These addresses are part of the class C range and are reserved for local communications within a private network
Types of Network Traffic
TCP/IP
This protocol is used for establishing and maintaining connections between AIM & Endpoints, as well as for non-video service traffic between endpoints.
UDP
This protocol is used to send streaming video and audio data between Infinity endpoints, once connections are established.
Types of Packet Delivery
Unicast
Unicast IP refers to data packets sent from a source to a single destination
Multicast
Multicast IP refers to data packets sent from a source to multiple desired destinations
Broadcast
Broadcast IP refers to data packets sent from a source to all destinations, desired or not
Network Address Translation
What is it?
NAT is a technique used to MAP multiple "Private IP Addresses" within a local network, to a "single public IP" before sending data on the internet.
Why do we need it?
In your home network you have several devices (computers, smartphones, tablets, smart TVs etc.) Each of these has a private IP address within your local network.
When the devices need to access the internet, they need to do so using a public IP address.
NAT bridges the gap by translating private IP addresses to a shared Public IP address before sending the traffic out to the internet.
How does it work?