Summary
Highlights
The video opens by illustrating the complex process of a simple action like clicking a YouTube video, highlighting how messages travel across vast distances and are interpreted by computers. It sets the stage for exploring the history of this interconnected world.
The concept of making computers work together began during World War II. Richard Feynman's team devised a method to run multiple problems simultaneously on early, large computers. In the 1950s and 60s, a separation of computer terminals from the main computers emerged, an early form of 'cloud computing' that allowed more users to experiment with these machines.
The US Department of Defense's ARPA (Advanced Research Projects Agency) funded research into a computer network at the suggestion of Joseph Licklider. In 1969, ARPANET was launched, connecting four universities and laying the foundation for future internet technologies. Its engineers would continuously add features and solve problems that still shape online interactions today.
ARPANET's initial major innovation was packet switching, a departure from circuit switching used in traditional telephony. Unlike circuit switching, which requires a dedicated, uninterrupted connection, packet switching allows multiple computers to send messages (packets) along the same wires. Each packet has an address label, enabling it to be routed efficiently through various computers until it reaches its destination, making the internet scalable and practical.
Initially, packet switching worked well, but as ARPANET grew, maintaining an updated list of all computer addresses became problematic. In 1973, Stanford became the official record-keeper of addresses. ARPANET continued to expand globally, connecting computers in the US, Hawaii, England, and Norway throughout the 1970s.
By the mid-1970s, many other networks emerged, but their differing packet formats made interconnection difficult. The solution, implemented by the early 1980s, was TCP/IP (Transmission Control Protocol/Internet Protocol). TCP standardized packet formatting, and IP standardized addressing, making it significantly easier to connect diverse networks and forming the core of what became known as the Internet.
With the Internet's rapid growth, the centralized address-keeping system at Stanford became overloaded. Email, invented in 1971, also became cumbersome to send due to the need for users to manually map out packet paths. The Domain Name System (DNS) was developed to reorganize hosts into domains (like '.com' or '.edu'), significantly simplifying address management and email routing by creating a dedicated network for tracking addresses and connections. DNS still functions this way today.
By the late 1980s, ARPANET had far exceeded its initial goal of connecting a few reliable computers, fostering a global network. The Department of Defense decided to end the ARPANET project, posing new questions about who would manage this increasingly vast and crucial network and how it could become accessible to the general public. These questions will be addressed in the next episode of the series.