Internet Protocol facts for kids

The Internet Protocol (or IP) is a super important set of rules that helps computers talk to each other on the internet. It's like the main language the internet uses to send information around the world. IP works closely with another set of rules called the Transmission Control Protocol (or TCP). Because they work so well together, they are often called TCP/IP.

Imagine you want to send a letter to a friend. You write the letter, put it in an envelope, and write your friend's address on it. Then you drop it in a mailbox. You don't have a direct string connecting your house to your friend's house. Instead, the postal service takes your letter and sends it through many different places until it reaches your friend.

IP is a lot like the postal service for the internet. It makes sure that small pieces of data, called packets, know where to go. TCP then makes sure that all these packets arrive safely and in the right order, checking for any mistakes along the way.

How IP Works

The Internet Protocol helps send information from one computer to another. It breaks down the information into small pieces called packets. Think of these packets as tiny digital envelopes.

There are two main versions of IP used today: IPv4 and IPv6. IPv4 is the older and most common one, but IPv6 is becoming more popular. IP also gives every computer connected to the internet a special number called an IP address. This is like a unique street address for your computer.

IP's main job is to deliver these packets from a starting computer to a receiving computer. It does this by adding address information (like a label) to each packet. This process is called encapsulation.

Just like a package might be split into several boxes for shipping, information on the internet is often split into many packets. Each packet has the address of the computer it needs to reach. These packets might even travel different paths to get to the same place, but IP helps them all arrive at their destination.

IP Packets

Each IP packet has two main parts:

• The header is like the label on an envelope. It contains important information, such as the IP addresses of the sender and the receiver.
• The payload is like the letter inside the envelope. This is the actual data or information being sent.

Adding the header to the data is called encapsulation.

Routing Packets

When you send information online, it doesn't go directly from your computer to another. Instead, it travels through many other computers called routers. These routers are like traffic cops for the internet. They read the header of each packet to see its destination IP address. Then, they figure out the best path to send the packet to the next router on its way to the final destination. This process is called routing.

Routers use special rules, called routing protocols, to decide where to send packets. This all happens incredibly fast, almost at the speed of light, so your messages and videos arrive quickly!

Staying Connected

The internet was designed to be very strong and reliable. Even if some parts of the network stop working, the rest of the internet can still keep sending information. This is because there isn't one central control point. Instead, the "smart" parts of the network are at the very ends, on your computer and the computer you're talking to. This idea is called the end-to-end principle.

IP itself sends packets without promising they will arrive safely. This is called best-effort delivery. It means packets might get lost, mixed up, or arrive out of order. But don't worry! Higher-level rules like TCP are there to make sure everything arrives correctly. IP is also connectionless, meaning it doesn't keep a continuous connection open between two computers. It just sends packets one by one.

Older versions of IP, like IPv4, use a special code called a checksum to check for errors in the packet's header. If a router gets a packet and the checksum doesn't match, it knows something went wrong and throws the packet away. Newer versions, like IPv6, don't use this checksum because other rules (like TCP) already check for errors, which helps make things even faster.

History of IP

The idea for the Internet Protocol started in 1974. Researchers wanted to find a way for different computers to talk to each other using packet switching. They first thought of a big "Transmission Control Program." But this program was too big, so they split it into two main parts: TCP and IP. This is why we often talk about the TCP/IP Model today.

The very first experimental versions of IP were used between 1977 and 1979.

One challenge with IPv4 is that it has a limited number of unique IP addresses. With so many devices connecting to the internet, we are starting to run out of IPv4 addresses. To solve this, a new version called IPv6 was created. While IPv4 has about 4.3 billion addresses, IPv6 has a huge number – 340 undecillion addresses! That's a 340 followed by 36 zeros, so we won't run out of IPv6 addresses anytime soon.

Images for kids

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  First Internet demonstration, linking the ARPANET, PRNET, and SATNET on November 22, 1977

See also

In Spanish: Protocolo de internet para niños