When computers need to communicate with each other on a network, they use IP addresses to identify and locate the devices they want to connect with. An IP address is a unique numerical identifier assigned to each device on a network. It consists of four sets of numbers separated by dots, such as 192.168.0.1.
IP addresses are used to route data packets from the sender to the receiver on a network. When a computer wants to send data to another device on the network, it looks up the destination device’s IP address and includes it in the packet header. Routers on the network then use the IP address to forward the packet towards the destination.
In summary, computers use IP addresses to find and communicate with other devices on a network.
What is an IP address?
An IP address is a unique identifier assigned to a device or network that uses the Internet Protocol for communication over the internet. Internet protocols manage the process of assigning IP addresses to devices and also route internet traffic. IP addresses serve the same purpose as telephone numbers, by identifying devices and enabling communication over the internet.
There are two types of IP addresses: IPv4 and IPv6. IPv4 addresses consist of a series of four numbers separated by periods, while IPv6 addresses are represented as eight groups of four hexadecimal digits separated by colons.
To find your IP address, you can use a cheat sheet that shows how to locate your IP address on either Mac or Windows operating systems.
The parts of your IP address
An IP address consists of two parts: the network ID, which is made up of the first three numbers of the address, and a host ID, which is the fourth number in the address. For instance, in the IP address 192.168.1.1, 192.168.1 represents the network ID, while the final number is the host ID.
The network ID identifies the network to which the device is connected. The host ID refers to the specific device on that network. Typically, the router is assigned .1, while each subsequent device is given .2, .3, and so forth.
However, there may be times when you don’t want others to know which device and network you are using. In such cases, you can use a Virtual Private Network (VPN) to hide your IP address from the outside world. When you use a VPN, it prevents your network from revealing your address.
Where do IP addresses come from?
- IPv4 was created in the early 1980s when the internet was still a private network used by the military. It has a pool of 4.3 billion addresses, which used to be sufficient. However, with the increasing number of devices connecting to the internet, such as computers, smartphones, tablets, and IoT devices, we have run out of IPv4 addresses. Although some technical networking tricks have been implemented to work around the shortage, the depletion of IPv4 addresses began as early as the 1990s.
- To address this issue, the Internet Engineering Task Force (IETF), which designs internet technologies, created IPv6 about a decade ago. IPv6 has a potential pool of 340 undecillion addresses, which means we will never run out of addresses in theory. Although IPv6 is slowly replacing IPv4, both protocols coexist for now.
Public vs. local IP addresses
There are two types of IP addresses: external or public IP addresses and internal, also known as local or private addresses. Your internet service provider (ISP) provides you with your external address. When you access a website, the site needs to identify you for traffic-monitoring reasons. Your ISP uses your external IP address to introduce you to the website and establish a connection.
For internal purposes, such as identifying your devices within a home network or business office, you have a different IP address. The local or internal IP address is assigned to your computer by the router, which is the hardware that connects a local network to the internet. In most cases, this internal IP address is assigned automatically by the router or cable modem.
It is important to note that in most cases, you will have a different IP address internally than the one you have on the public internet. Your local IP address represents your device on its network, while your public IP address is the face of your network to the greater internet.
How do IP addresses work?
An IP address serves as a digital marker for the virtual location of a computer, website, network server, or other devices. Similar to how the post office uses physical addresses to route mail, IP addresses route internet traffic and direct emails to their destination. It’s an essential component of sending and receiving information over the internet.
It’s worth noting that every active device connected to the internet has an IP address, making it an integral part of how the internet functions.
- IP addresses are just one component of the internet’s infrastructure. Without a functioning post office to deliver mail, your physical address is irrelevant. In the same way, TCP/IP is the backbone of the internet, with IP being just one component.
- TCP/IP is a set of regulations and procedures used to link devices on the internet. It describes how data is transmitted between devices: information is divided into packets and passed through a series of routers from its origin to its destination. This is the foundation of all internet communication.
- TCP defines how applications interact across the network. It manages how messages are separated into smaller packets that can be sent over the internet and reassembled in the right order at the destination.
- The IP component of the protocol ensures that each packet reaches its intended destination. Each gateway computer on the network uses the IP address to determine the proper path for the message.