What Is ARPANET? The Evolution to the Modern Internet

We rely on the modern Internet for communication, sharing, learning, and so much more. But most people don't know how the the Internet came to be. Though the modern Internet originated in the 1990s, the predecessor to the Internet - known as ARPANET - existed years prior. In this article, take a closer look at the history of ARPANET and learn about its influence on the development of the Internet as we know it today.

What is ARPANET?

ARPANET (Advanced Research Projects Agency Network) is the first operational packet switching network that allowed for the sharing of information and resources between different institutions. It was designed to connect research institutions, government agencies, and military installations.

The network was built to be redundant, and messages could be routed through multiple paths to reach their destination. It was a major breakthrough in computer networking technology because it paved the way for the development of the Internet.

ARPANET allowed researchers to share information across different institutions, which was an important development at a time when computers were still limited in their overall capabilities. It also had a significant impact on the development of network protocols. The network used the NCP protocol, which later evolved into the TCP/IP protocol suite that powers the Internet today. TCP/IP is a set of protocols used for transmitting data over the Internet and is essential for the functioning of the World Wide Web.

Another important aspect of ARPANET was its culture of openness. By design, the network facilitated collaboration between different organizations. The spirit of collaboration and sharing has continued to be a defining feature of the Internet.

Development of ARPANET

ARPANET was developed by the United States Department of Defense in the 1960s. It was a time of heightened tension during the Cold War, and the U.S. government recognized the need for a decentralized network that could continue to function even after the destruction of certain parts.

Its formulation was not the outcome of a single individual or organization. Instead, it was the product of collaborative efforts involving many people over several years. In the 1960s, computers existed as large mainframe systems owned by major entities like companies, universities, and governments. Users then interacted with these systems through dedicated terminals.

Dedicated links established the connections between computers, creating highly fault-prone systems. In the early 1960s, Paul Baran's work on packet switching provided a critical foundation for reliable data transmission over shared network resources.

Then, in 1962, J. C. R. Licklider became the first head of the Information Processing Techniques Office (IPTO) at ARPA. It was later in this role that Licklider proposed the idea of a "galactic network" that would allow researchers to share information across the globe. This, eventually, became the Internet.

Key milestones in ARPANET's development

ARPANET achieved several key milestones during its development.

First ARPANET connection

The first message sent over ARPANET was on October 29, 1969, between the Network Measurement Center at UCLA and the Stanford Research Institute. Charley Kline, a graduate student at UCLA, attempted to send the message "login" to the Stanford computer. However, the system crashed after he sent the first letter. Subsequently, the first successful message sent over ARPANET was "LO," transmitted over UCLA's computer to the Stanford Research Institute's computer.

Packet switching

ARPANET pioneered the use of packet switching, a method of transmitting data in small packets. This laid the foundation for modern Internet communication.

Development of email

In 1971, Ray Tomlinson developed the first email program. It allowed users to send messages across the network between different hosts. He established the use of the '@' symbol in email messaging, making it simple for users to send messages digitally across the ARPANET.

TCP/IP protocol

In the 1970s, the Transmission Control Protocol/Internet Protocol was developed, providing a standardized method for data transmission and enabling the growth of the Internet. This protocol is still the standard for the Internet today.

The role of learning institutions in intranet development

Universities and research institutions were at the forefront of technological advancements throughout the entire process. They provided the necessary expertise and resources to push the boundaries of networking. The research institutions actively collaborated with each other and with government agencies to design the infrastructure required for ARPANET.

One notable example is the University of California, Los Angeles (UCLA). UCLA's Network Measurement Center, led by Leonard Kleinrock, was responsible for developing the first host-to-host connection on ARPANET in 1969. This achievement marked a major milestone in the history of computer networking.

Another important institution involved in ARPANET's development was Stanford Research Institute (SRI). SRI's Network Information Center (NIC) played a crucial role in managing the network and providing support to the growing number of connected hosts. The NIC was responsible for assigning unique network addresses.

ARPANET evolves into the Internet

In the first half of the 1980s, the Defense Advanced Research Projects Agency (DARPA) started developing a new protocol suite called TCP/IP, designed to replace the Network Control Program (NCP) used in ARPANET. TCP/IP was essentially a networking protocol that allowed different networks to communicate with each other. It was this development that helped pave the way for the transformation of ARPANET into what we now call the Internet.

The Internet continued to grow rapidly in the United States. By the late 1980s, it was clear that the Internet had become an essential communication tool. The emergence of email, file sharing, and bulletin board systems all provided further impetus for the expanding Internet.

The Internet's transformation from ARPANET into the current global network occured thanks to several key factors, including:

• Better technologies. Advanced protocols like TCP/IP allowed different networks to communicate that led to the development of the Internet.
• Increased collaboration. The networking community worked hand-in-hand across institutions and organizations to bring the Internet to life.
• Increased funding. The US government provided increased funding for network research and development, which helped accelerate the growth of the Internet.
• Rapid technological advancements. Advancements in computer hardware and software, including personal computers, led to increased demand for networking capabilities.

The impact of ARPANET

The transformation of ARPANET into the Internet has been instrumental in shaping modern society. The development of the Internet has revolutionized the way people communicate and share information.

It has created a new era of instant communication where people from all corners of the world can connect in real time. The Internet has brought about a significant shift from traditional communication methods to digital communication through social media, messaging apps, video conferencing, and email.

The Internet has vastly improved access to information. With just a few clicks, anyone can access a wealth of knowledge on any subject imaginable. Educational resources, research papers, news articles, and online libraries are accessible from anywhere. This has led to a democratization of information where knowledge is no longer restricted to the private few.

The Internet has also transformed the way business operates. Companies can reach new customers and equally expand their market reach through online platforms. E-commerce has made it possible for businesses to sell their products to customers across the globe.

Frequently asked questions

What were ARPANET's early challenges?

ARPANET faced limitations such as early technical constraints, scalability challenges, and evolving communication protocols. Initial infrastructure hurdles and adapting to varying computer systems presented obstacles. But the researchers learned from these challenges to develop more robust network technologies.

How did ARPANET impact communication and technology?

Throughout the ARPANET history, the program revolutionized communication and technology. It introduced concepts like packet switching, email, and remote access, which are now fundamental to our digital lives.

What was the purpose of ARPANET?

ARPANET aimed at developing a reliable communication network that could withstand a nuclear attack. It sought to facilitate the exchange of information and resources between geographically dispersed computers.

What was the significance of the first ARPANET message?

The successful transmission of the first message paved the way for further advancements in computer networking technology, eventually leading to the creation of the Internet.

What is the ARPANET definition?

ARPANET is defined as the first functional packet-switching network, allowing companies, universities, and businesses to communicate and share data across distances.

When was ARPANET created?

ARPANET was created in the 1960s and was first used in 1969.

What is ARPANET's legacy?

ARPANET's legacy lies in transforming communication, fostering collaborative research, and influencing the development of the global, interconnected Internet.