ISI: Internet Innovator for the Past 50 Years

| September 6, 2022

As we celebrate the 50th anniversary of USC’s Information Sciences Institute, we take a look back at its role in the development of the defining technology of our age: the internet.

Photo credit: Melpomenem/Getty Images

Photo credit: Melpomenem/Getty Images

From its founding in 1972, USC’s Information Sciences Institute (ISI) played a pivotal role in conceiving, designing and implementing the internet. It was home to many internet pioneers – Steve Crocker, Jon Postel, Danny Cohen, Paul Mockapetris, Dan Lynch, Bob Braden – these are names that go down in internet history, and up on the (virtual) walls of the Internet Hall of Fame. And they are just some of the ISIers who have made extraordinary contributions to the internet. From their offices in Marina del Rey in California, while overlooking the Pacific, they worked to make crazy concepts come to life and allow big ideas to flourish.

The Wild Idea of Networked Computers 

In the late 1960s, shortly before ISI was founded, the idea of networking different computers together was nothing more than that – an idea. The Advanced Research Projects Agency (ARPA, renamed DARPA in 1972) issued a request to see if it could be done and soon, ARPAnet was born. It was the first computer network to connect different organizations together using packet-switching. What’s packet-switching? A method of grouping data for transmission over a digital network – the now-universal technology that underlies all modern networking.

By 1969, the first message was delivered from one computer to another. And soon, previously incompatible computers across the country were networked via ARPAnet and being used in academia and research. Next thing you know, similar networks were created worldwide. The challenge of connecting those networks would be solved by Bob Kahn and Vint Cerf, who unified the networks, creating what we now call “the Internet.” They were joined by a dedicated team of innovators across research and academia, including (notably, for the purposes of this article) Steve Crocker and Jon Postel, both of whom would soon come to work at ISI.

And in 1972, just as the first ISIers were setting up shop in Marina del Rey, networked computers were becoming a thing. 

Who Is Going to Maintain this Thing

Keeping track of the different networks across the globe; maintaining addresses and names; recording protocols – the system of rules, syntax, and semantics of information transmission; these were now the challenges at hand. And ISI was all set up, and ready to take them on.

Rules of the Road: TCP/IP
Early network developers used different hardware and software specifications, making it impossible for networks to communicate with each other. In 1974, Cerf and Kahn proposed a solution: a standardized set of rules that allowed computers to communicate across networks. Those rules were the Internet Protocol (IP) and the Transmission Control Protocol (TCP). Essentially, IP delivers packet of data, and TCP ensures that it’s delivering them reliably. Over the years, these protocols were revised and refined into what are now the core specification documents of the internet; the element that makes global networking possible. Jon Postel and other ISIers were part of the team that refined TCP and IP. Postel was so involved, in fact, that the final TCP/IP documents published in 1981 were “prepared for DARPA by ISI” with Postel listed as the Editor.

TCP/IP is so crucial to how the internet functions, that the date of its deployment, January 1, 1983, is often considered the birth date of the internet. Researcher and developer Dan Lynch, who had helped develop TCP/IP and was now working at ISI, led the team that transitioned ARPAnet onto the new TCP/IP protocols. 

The Internet Operating Manual: Request for Comments
Every new innovation needs a set of instructions; for the internet, it’s the Request for Comments papers (RFCs). They are essentially the operating manual; the written record of the internet’s technical structure and how it operates.

After working on ARPAnet as a grad student at UCLA, Jon Postel joined ISI. Back at UCLA, he had been responsible for recording and editing the RFCs. Postel brought these early papers to ISI, quite literally – old paper files and black leather-bound log books that lived in his ISI office. For over 20 years, the ever-growing list of documents was hosted and maintained at ISI by Postel and the RFC-editor team. Those early RFCs shaped the internet’s inner workings at a time when they were just being established. Though no longer hosted at ISI, this series of documents has grown to over 9000 RFCs, and it has become the mainstay for both sharing technical designs and catalyzing innovation in the internet community

Bookkeeper of the Net: Internet Assigned Numbers Authority
In those early days of networking, in order to communicate with a computer, you needed its numeric address (think: At first, computer scientists and researchers kept their own lists of computer names and addresses. It’s been said that Bob Kahn carried a three-by-five index card in his shirt pocket to keep track of the addresses of all the networked computers. By 1974, index cards (and the like) were replaced by a centralized text file of all the host names and addresses, but as the number of internet hosts quickly went from dozens to hundreds to thousands, the question became: who will assign all of these addresses?

The answer (again) was Jon Postel. Years earlier, Postel had informally established the Internet Assigned Numbers Authority (IANA), referring to the various technical functions he did for ARPAnet. By 1988, IANA would codify into the official authority for assigning names and numbers for use on the internet.

Postel was the Director of IANA, which put him in charge of handing out blocks of IP addresses to the people who were running the various networks. Individual network operators would then assign addresses to specific machines in their network. The only way to get one of those address blocks was to contact Postel. You read that right: anyone who wanted to add a network to the internet had to go through Jon Postel at ISI.

This job became so important that, in 1997, The Economist magazine proclaimed, “If the Net does have a god, he is probably Jon Postel.” And the “god” of the internet was managing key parts of the internet infrastructure out of his ISI office until his death in 1998. As internet usage exploded, the responsibility for address allocation transitioned to ICANN – the Internet Corporation for Assigned Names and Numbers – an organization that was created in response to a U.S. government request to privatize certain internet systems.

What’s In a Name?: Domain Name System
As the number of computers coming online increased, and IANA/Postel was doling out blocks of addresses, the need for a systematic and scalable approach to naming arose. In 1983, ISI’s Paul Mockapetris (working as a graduate student for Postel) created the Domain Name System (DNS). This innovation completely changed the trajectory of the internet by allowing it to grow by orders of magnitude.

Before DNS, the network was limited to managing tens or (maybe) hundreds of computer names and addresses due to technical and administrative constraints. But with the DNS, the job of looking up the mapping from a name to an address was split across a large network of servers – a distributed database of domain names and IP addresses – rather than one central server. This meant that as more domains were added, more servers could be added too. With this innovation, the DNS could match millions of human-friendly names with their corresponding IP addresses.

The DNS also supported the new “dot” system of naming (developed, in part, at ISI), which divided the internet into “.com,” “.org,” “.edu,” and more. This now meant that names had a hierarchy so that, for example, the owner of the domain could assign new names to machines in their own network and not worry that one of those names might be taken. This was a key idea behind a system that could now have millions of names rather than a few hundred.

To support the DNS, one of the first root servers – which play a critical role in the translation of the human-friendly host names to numeric IP addresses – was set up at ISI. That server, “B-root”, is one of 13 in the world and a key piece of Internet infrastructure that is still operated by ISI to this day.

What Else Can We Do With This Thing

From the First Conference Call to the Now Ubiquitous Zoom
Back when ARPAnet got up and running, suddenly anything seemed possible. While Postel and team were just getting started on TCP/IP, RFCs, IANA, and the DNS, another group of ISIers was on to something else. ISI researcher Danny Cohen was working on transmitting flight simulators over ARPAnet. In 1973, he was the first person to send voice and video over a network in real-time. The original webcast!

As Cohen’s team was working on that, DARPA was looking for a way to send voice over the network in a quick, secure and encrypted way – they wanted to send voice messages to spies! They approached Cohen, and in 1973 he and his ISI team demonstrated the first version of “voice over IP” (VoIP), or real-time online voice communications. By 1974, they created two-way communications over IP; and by 1978 they completed the first conference call. In 1980, using a satellite on ISI’s roof, Cohen and ISI researcher Stephen Casner were the first to use satellite to transmit video over a network; and in 1986, the duo held the first real-time multimedia teleconference using packet video over the internet, including text and graphics displayed at both ends of the meeting.

Casner continued to research video over the internet at ISI and, in 1992, he co-created multicast multimedia transmissions over the internet (Mbone). Two years later, on November 18, 1994, Mbone was used to broadcast a live entertainment event – a Rolling Stones concert – worldwide via the internet for the first time. All of this work paved the way for livestreaming, Skype, Zoom and more.

Show Me the Money
Around this time, ISI researchers were looking at what other possible services and applications would be needed in the burgeoning internet. In 1993, Clifford Neuman and his ISI team created two of the earliest electronic payment systems suitable for micropayments on the World Wide Web: NetCash and NetCheque. Originally developed to pay for information online, they enabled new types of services on the internet that were previously impractical because of the lack of secure and efficient payment methods. The next year, Danny Cohen created the FastXchange brokering system, a pioneering online business. 

How Do We Keep This Thing Safe? 

Prior to the 90s, much of the work being done in internet security could be seen as theoretical. But once electronic payments and e-commerce were developed, and there was money online, bad actors on the internet had motive and security came to the forefront of internet innovation.

One of the biggest early security problems for the internet was that it was difficult to know who was on the other end of a connection. Before coming to ISI, while he was at MIT, Neuman co-developed the Kerberos authentication system – which verifies user identities. Upon moving to ISI in the early 90s, he and his team (including Brian Tung and other ISIers) played a significant role in the design, extensions to, and standardization of the protocol. This is a system that is still used today and is integrated into all major operating system ecosystems.

In the 80s and 90s, the internet transformed from a place for researchers and academics, to a place for regular people. And along with regular people, come bad people. By the 2000s, the focus shifted to cyber-defense because it was clear that there were malicious actors on the internet.

In 2003, ISI collaborated with UC Berkeley to create the cyber-defense research facility DETER. DETER – which stands for cyber DEfense Technology Experimental Research – was set up to address the issue of increasing cyber-threats. The pace of those threats was accelerating, but the stream of new and effective cyber-defense technology was lagging. ISI researchers realized that those original internet protocols weren’t designed with security in mind, and if you have an open network like the internet, its resilience to malicious actors needs to be high. DETER became such an authority that, in 2013, DETER co-director Terry Benzel testified before the U.S. Congress about the need for new cybersecurity approaches and technologies. Today, ISI continues to lead the charge in keeping the internet safe with DETER. 

Where Do We Take This Thing From Here? 

From the conception of the internet, ISI has played a key role. From its design to its management; its implementation to its applications in the world, ISI has been pivotal. In finding ways to keep it secure, ISI continues to innovate. And the internet community is taking note of ISI’s contributions. Since the establishment of the IEEE Internet Award in 1999, six ISIers have been recipients – Steve Crocker, Paul Mockapetris, Deborah Estrin, Eve Schooler, Stephen Casner, Mark Handley, Ramesh Govindan and upcoming in 2023, Carl Kesselman – a testament to ISI’s continued work on the advancement of internet technology.

Today, ISI researchers are using the internet to conduct research in a whole host of areas that were previously impossible. Connecting liver researchers worldwide. Fighting for fairness in online job ads. Modeling climate change. Tracing the extinction of monkeys. Creating better soybeans. Improving the resilience of communities against flash floods, wildfires and earthquakes. Combating human trafficking. ISI researchers are pushing the limits of networking, the internet, data and more into the future. 

Published on September 6th, 2022

Last updated on May 16th, 2024

Share This Story