Hello! Welcome to the first lesson of our course on the history and workings of the internet.
Our goal is to journey from the initial concepts that sparked the internet's creation to the complex, global network we use every day. We'll balance historical context with the technical details, connecting the "book knowledge" to what's happening on your screen and in the wires around you.
This first module, "The Birth of the Internet," sets the stage. In this lesson, we will focus on understanding the world before the internet. Specifically, you will learn to describe the problem of long-distance computer communication in the 1960s. We'll explore the technological, logistical, and geopolitical challenges of that era which created the necessity for a new kind of network.
Let's begin by looking at how computing worked back then.
The Problem of a Single, Busy Computer
In the 1950s and 1960s, computers were not personal devices. They were enormous, room-sized machines called mainframes that cost a fortune to build and operate. Because of their expense, organizations needed to use them as efficiently as possible. This led to a workflow called batch processing.
Imagine you wrote a program on punch cards. You would hand your stack of cards to a computer operator, who would add it to a "batch" of other programs. Hours later, the entire batch would be run, and you would receive a printout of your results. If you had a single typo, you'd only find out after this long wait and have to start the whole process over. There was no direct, real-time interaction with the computer.
This was a major bottleneck. To understand this problem and the first major step toward solving it, please watch the following clips from a fascinating 1963 program about a new concept called "time-sharing."
1963 Timesharing: A Solution to Computer Bottlenecks
This video from the Computer History Museum features MIT's Dr. Fernando Corbató explaining the frustrations of batch processing and introducing the revolutionary concept of time-sharing.
Please watch the following three segments: The Inefficiency of Batch Processing (2:02 - 4:43): Pay attention to how Dr. Corbató describes the poor 'man-machine interaction' and the long delays involved. Introducing Time-Sharing (4:43 - 5:46): Note the proposed solution: connecting multiple remote consoles to a central computer. How Time-Sharing Works (12:56 - 14:55): Focus on the 'Chessmaster' analogy, which is a brilliant explanation of how a single computer can serve many users by rapidly switching between them.
As you saw, time-sharing was a groundbreaking idea. By allowing multiple users to connect to a single mainframe from remote terminals (often modified typewriters), it created the illusion that each person had the computer's full attention. This move from batch processing to interactive computing was a crucial first step.
However, time-sharing only solved the problem of many people accessing one computer. A bigger problem loomed: how to get different, incompatible computers to talk to each other across long distances.
The Problems of a Divided, Distant World
In the 1960s, two major forces converged to make the problem of connecting computers a top priority: geopolitical tension and the needs of the research community.
1. The Cold War and the Need for a Resilient Network
The space race and the Cold War between the United States and the Soviet Union created a powerful incentive for technological advancement. The U.S. government, worried about its ability to communicate after a potential nuclear attack, needed a communication network that was decentralized and could withstand the loss of several nodes.
To understand this context, let's watch a short video that explains the founding of the agency that would ultimately build the internet's forerunner.
This video explains the geopolitical climate of the late 1950s and 60s, which led to the creation of the Defense Advanced Research Projects Agency (DARPA).
Watch from 3:25 to 5:25. Focus on why the launch of Sputnik prompted the creation of DARPA and how this led to the need for research centers to be in constant contact.
This strategic military requirement for a survivable, decentralized network was a primary driver. But it was combined with a very practical, and frustrating, problem faced by the very researchers DARPA was funding.
2. Incompatible Systems and Inefficient Connections
DARPA sponsored computer science research at universities and institutions across the country. Each of these locations had its own unique, time-sharing mainframe computer, often from different manufacturers like IBM, DEC, and GE. These systems were completely incompatible; they couldn't run the same software or exchange data directly.
To get a clearer picture of these challenges, please read the following material from the Computer History Museum and Encyclopedia Britannica.
Internet History of 1960s & ARPANET
These readings detail the technical and logistical problems that researchers faced in the 1960s. They introduce key figures and the specific issues they were trying to solve.
From the Computer History Museum's "Internet History of 1960s" article, please read the sections for the years 1962 through 1966. Focus on two key points: The 1965 experiment connecting two computers via a telephone line, which proved that this method was 'inefficient, wasteful of bandwidth, and expensive.' Bob Taylor's predicament in 1966 with three separate terminals in his office to connect to three different, incompatible computers.
ARPANET | Definition, Map, Cold War, First Message, & History
This second reading reinforces the military context and clearly articulates the problem of incompatible systems that Bob Taylor observed.
In the Britannica article on ARPANET, please read the introduction (the first two paragraphs) and the section titled 'Ivan Sutherland succeeded Licklider...'. Focus on how it describes the initial purpose of ARPANET and re-tells the story of Bob Taylor's frustration with his three separate terminals.
Summary of the Problem
Let's pull these threads together. By the mid-1960s, the world of computing faced a multi-faceted problem that prevented the creation of a large-scale network:
- The Interoperability Problem: Researchers at different sites had no way to collaborate. A researcher at MIT couldn't easily log into a computer at UCLA to run a program or access a file because the systems were fundamentally incompatible.
- The Inefficiency Problem: The only existing way to connect computers over long distances was to use the telephone network. This required leasing a dedicated, point-to-point phone line for the entire duration of the connection, which was incredibly expensive and wasted most of the line's capacity (bandwidth).
- The Strategic Problem: The U.S. military required a communication network without a central point of failure that could continue functioning even if parts of it were destroyed. The existing telephone network, with its centralized switching centers, was too vulnerable.
These challenges created a clear need. The solution couldn't just be more telephone lines. It had to be a completely new way for computers to communicate—one that was efficient, flexible, and robust.
Conclusion
In this lesson, we've established the critical problems that set the stage for the invention of the internet.
Key Takeaways:
- Early mainframe computers were isolated and inefficiently used via batch processing.
- Time-sharing introduced interactive computing and remote access, but only for a single, centralized computer.
- The Cold War created a military demand for a decentralized and damage-resistant communication network.
- Computer researchers were isolated by incompatible systems and the high cost and inefficiency of using dedicated telephone lines for data transfer.
These combined pressures created the perfect environment for a radical new idea.
Preview of the Next Lesson:
In our next lesson, we will explore the elegant and revolutionary solution to these problems: packet switching. We'll examine how this concept differs from the circuit-switching of the telephone network and why it became the fundamental principle upon which the internet is built.