How the World Got Wired · The Constitution

January 1, 1983

For ten years after Cerf and Kahn’s paper, TCP/IP was tested, revised, and improved by engineers all over the world. By the early 1980s, ARPA had decided to make it official. The old ARPANET, which had been using an older set of rules, would switch over to TCP/IP on a specific day.

That day was January 1, 1983.

The engineers called it flag day — the day everyone had to change. If your computer wasn’t speaking TCP/IP by the end of January 1, it would no longer be able to talk to the ARPANET. The instructions had been sent out for months. Universities and labs had been preparing. The switch flipped on New Year’s Day.

A lot of things broke. A lot of things had to be fixed in the first few weeks. But by February of 1983, the network was running on TCP/IP, and it has been running on TCP/IP ever since.

Most people who study the history of the internet consider January 1, 1983 to be the actual birthday of the internet. The ARPANET had existed since 1969. But the internet — the network of networks, all able to talk to each other through a common language — that started on New Year’s Day, 1983.

There were maybe a few hundred computers on it.

Today there are more than ten billion devices. Your phone is one of them. So is mine. So is the security camera near your door, the watch on your wrist, the thermostat on your wall, and a satellite that is, at this moment, somewhere over the Pacific Ocean. All of them are speaking the same language two men sketched out in a hotel room in 1973 and gave away for free.

The Network with No Boss

There is one last thing I want you to understand about TCP/IP before we move on.

The way Cerf and Kahn designed it, the internet has no boss.

No one is in charge of it. No company owns it. No country runs it. There is no central office that decides who is allowed to join, or what is allowed to travel through it, or what the rules will be next year. The rules — the protocols — are written and updated by groups of engineers from many countries, who meet, argue, write papers, and propose changes that anyone can read. When most engineers and companies agree a change is good, they adopt it. When they don’t, they don’t.

The network itself doesn’t know what’s inside the packets. It doesn’t know whether it’s carrying an email, a video of a grandmother, a picture of a cat, a bank transfer, a love letter, or instructions for a missile. It just moves packets from address to address, as fast as it can, with no opinion about what they say.

This design choice is one of the most consequential things any group of engineers has ever decided. It is the reason the internet has been used for so many beautiful things — connecting families across oceans, sharing knowledge that used to be locked in expensive libraries, letting people in distant countries talk to each other. It is also the reason the internet has been used for ugly things — for crime, for harassment, for spreading lies. A network with no boss has no one to stop bad people from using it. The protocols carry the worst messages and the best ones equally well, because the protocols cannot tell the difference.

When you are older, you will hear adults argue about whether this design choice was wise. Some think there should be more control over the internet. Others think any control is dangerous. There is no easy answer. But you should know that the no-boss design was not an accident. It was a choice. It was made, mostly, by two engineers sitting in a hotel room near the San Francisco airport in 1973, deciding that the network should belong to everyone who agreed to follow a few simple rules.

In the next chapter, someone else will make the same kind of decision — to give away, for free, a piece of software that will transform the world. His name is Tim Berners-Lee. He works at a physics laboratory in Switzerland. He is going to invent something he calls the World Wide Web.

It is what most people today mean when they say the internet, even though it is actually a different thing — a thing built on top of the internet, using the protocols Cerf and Kahn gave away.

That’s Chapter 6.

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