Internet Protocol (IP) and Transmission Control Protocol (TCP) are the languages that computers use to communicate with each other, and they follow the rules of the Internet.
TCP/IP makes the Internet work a bit like a mailing system. There is an address book that contains the . contains identity of each device on the network, and a set of standard envelopes for packaging data. The envelopes must include the sender’s address, the recipient’s address, and details of the information packed inside.
The IP explains how the address system works while TCP explains how to package and send the data.
All computers get an IP address when they connect to the internet, according to: pc magazine, and they are all unique. You can find out yours by typing “what’s my IP” into Google. You will notice that it is not very people friendly. It contains either four numbers between 0 and 255, separated by periods, or eight sets of four digits, separated by colons.
You may also notice that your IP address does not stay the same. At home, you get your IP address from your ISP, but when you’re out and about, it could come from the Wi-Fi you connected to at a coffee shop, or from your corporate network, according to Business Insider†
How TCP/IP works
To load a website, your machine needs to know the IP address of the web server that holds the data. This is also a long string of letters and numbers, and it can also change unexpectedly.
Fortunately, there is a second address system that will help you direct your computer to the right place. Known as the Domain Name System, or DNS for short, it gives servers human-friendly names called domains cloudflare† Your web browser can look them up to find out which IP address to use.
Your computer can then connect to the server via a three-way handshake, according to the CISSP Study Guide† First, it sends a message to the server asking if it is ready to talk. It does this by sending a blank envelope with the word “sync?” written on the front.
When the server is ready, it writes “acknowledge” on a new envelope and returns it. Finally, your computer completes the connection by sending a third envelope that also says “confirm”.
Now you are ready to exchange data.
To do this, the server chops up the website’s content into small chunks and packs each into its own envelope. On the outside it writes its own IP address, your IP address and a tracking number, according to: cloudflare† That number tells your computer how to put the pieces back together.
When your computer receives one of the envelopes, it checks it and returns a message that reads: “confirm”. This means: “I have received the data and everything looks good.”
If the server does not receive an acknowledgment after a certain amount of time, it will assume that the envelope is lost or damaged and will resend it, according to IR technologies†
Once all the data is safe on your computer, all you need to do is disconnect. This includes another three-way handshake. One computer sends an envelope that says “complete”. The other sends back: “acknowledge”. The first replies with: “acknowledge”, and the connection is lost.
For more information on how the Internet functions, check out the many resources at the Internet Society and “Introduction to Networking: How the Internet Works” by DR. Charles R resigned.
- Eric Conrad, et al, “CISSP Study Guide (Second Edition)”, Syngress, 2012.
- IR Media, “What is Network Packet Loss?”, accessed April 2022.
- Cloudflare, “What is DNS? | How DNS Works,” accessed April 2022.
- Cloudflare, “What is TCP/IP?”, accessed April 2022.
- Dave Johnson, “How to Change Your IP Address to Troubleshoot Your Internet Connection or Protect Your Privacy” Business Insider, May 2021.