CCTP 820: Leading by Design: Principles of Technical and Social Systems – Fall 2017
By Linda Bardha
“The Internet has always been, and always will be, a magic box”. Marc Andreessen
There is something about this quote that just doesn’t seem right. I will admit it, I used to think like Mr. Andreessen. The internet, “this thing” that we use every day, is such a strange concept, and because we cannot physically see how the internet actually works, we don’t think twice and use the word “magic” to justify the work that is done in the background. But, the internet is not just an isolated box, and certainly it isn’t a magical box. Internet isn’t just a thing. The internet is a system of distributed agencies and technical meditations, that has changes the world that we live in. The internet is a product of its social environments, it has shaped the characteristics of communication media and information technology.
Major historical events lead to the creation of new technologies and developments. The Internet was born as a historical accident and different agents played significant roles in creating what the internet is today. The question that we need to ask regarding the Internet, is not about inventions or inventors, since as we will see, there are certainly a group of people, organizations and technologies that shaped The Internet that we use today. The more correct question would be to ask about the design principles, combinations of different methods and technologies that lead to the architecture that we use today. First, let’s start by taking a look at the historical events that shaped the Internet.
The history of the internet timeline
As Janet Abbate explains in her book “Inventing the internet”, The Internet and its predecessor, the ARPANET, were created by the US Department of Defense’s Advanced Research Projects Agency (ARPA), a small agency that has been deeply involved in the development of computer science in the United States. In 1957, USSR launched Sputnik into space and with it, global communications. In 1958, The United States government created the Advanced Research Projects Agency (ARPA) in response to Sputnik launch. ARPANET was a single network that connected a few dozen sites, which computer scientist used to trade files and information. Joseph C. R. Licklider, was the first director of ARPA’s Information Processing Techniques Office (IPTO). Licklider’s influential 1960 paper “Man-Computer Symbiosis” became an important document for computer science and technology to serve the needs and aspirations of the human user, rather than forcing the user to adapt to the machine. Licklider (1960, pp. 4–5) wrote:
“The hope is that, in not too many years, human brains and computing
machines will be coupled together very tightly, and that the resulting partner-
ship will think as no human brain has ever thought and process data in a way
not approached by the information-handling machines we know today. . . .
Those years should be intellectually the most creative and exciting in the
history of mankind”.
Another important figure that needs to be mentioned is Robert Taylor, a system engineer in the aerospace industry. He believed that if ARPA’s computers could be linked together, hardware, software and data could be efficiently pooled among contractors rather than wastefully duplicated(Abbate,2000). In 1966 Taylor recruited Lawrence Roberts, a program manager at MIT’s Lincoln Laboratory to oversee the development of the ARPANET. A group of computer scientists were constantly working in system-building strategies that used effective design principles such as layering and modularization. These two principles that were characteristics of the ARPANET, were later on, successful models that were used for the architecture of the internet. In 1967, Lawrence Roberts lead Arpanet’s design discussions and published first ARPANET design paper: “Multiple Computer Networks and Intercomputer Communication”. Wesley Clark, suggested that the network is managed by interconnected ”Interface Message Processors” in front of the major computers. Called IMPs, they evolved into today’s routers.
One of the major problems that the engineers and computer scientist were trying to solve while working with ARPANET, was designing a network that could allow any kind of computer to exchange data over a common network with no single point of failure. The concept of switching small blocks of data was first explored independently by Paul Baran. He described a general architecture for a large-scale distributed network. The main focus of his idea was to use a decentralized network, where a message could be successfully delivered between any two points, while using multiple paths. This message would be divided into different blocks, and then reassembled in the end when it reached the destination. In 1961, Leonard Kleinrock introduced the packet-switching concept in his MIT doctoral thesis about queuing theory: “Information Flow in Large Communication Nets”. His Host computer became the first node of the Internet in September 1969, and it was the first message to pass over the internet.
First, the TCP protocol breaks data into packets or blocks. Then, the packets travel from router to router over the Internet using different paths, according to the IP protocol. Lastly, the TCP protocol reassembles the packets into the original whole, and that’s how the message is delivered.
Working with this idea, were two other scientists Vint Cerf and Bob Kahn. According to Kahn, the origin of the word “the Internet”, is “inter-networking”. In the late, 1960s, he faced the problem of three communication networks that did not connect to each-other. He worked with Vint Cent to solve the problem. They invented an internetworking protocol to share information using packet-switching method. The Transmission Control Protocol (TCP) is the main protocol of the Internet Protocol (IP) suite. A lot of internet applications that share information over the internet, rely on TCP. So, the packet switching method for data protocols for any computer, provided the solution to the problem that I mentioned earlier. Now, any computer could exchange data over a common network, with no point of failure. This was a major invention that happened during the ARPANET research, and it is now one of the major main concepts of the networks that are connected today on the Internet.
In order for us to have a better idea of how the messages are sent from one point to the other, let us take a look at this video, where Spotify engineer, Lynn Root and Vint Cerf, an Internet pioneer, explain what keeps the internet running and how information is broken down into packets.
While the ARPANET was a single network that connected a few dozen sites, the Internet is a system of many interconnected networks, capable of indefinite expansions. At the start of 1980s, the internet was still under military control. (Abbate, 2000) But then, it shifted from military control to academic research. In 1983, the US Department of Defense split the ARPANET into MILNET which was a military site, and ARPANET which became a civilian research site. This division made possible for different scientists and organizations from around the world to do research and explore the possibilities of designing the internet’s architecture that we have today.
While the research was still going on, the idea to divide the internet space into smaller domains, was an invention by Paul Mockapetris. He invented the Domain Name System (DNS). Six large domain names were created to represent different types of network cites: edu (education), gov (government), mil (military), com (commercial), org (organization) and net (network). This division helped to categorize different types of networks and it made possible the idea to expand. Beneath the top level domains, were different categories, so under edu, each university would have it’s own domain and so on.
ARPA helped in funding the research that was done in creating a new generation of technologies for inter-networking, the concept of packet switching, the development of Transmission Control Protocol and Internet Protocol (TCP/IP), the concept of the “network of networks”.
So yes, the Department of Defense and the military programs that funded the research that was done, shaped the history of the internet that we use today. But, that is only one part of the big story. To make the global connections possible, different distributed agencies also known as the “Internet Ecosystem” help to develop the internet and make these connections possible. It is important to mention organizations such as the International Standard Organization (ISO), the Internet Engineering Task Force (IETF), the World Wide Web Consortium (W3C), the Internet Corporation for Assigned Names and Numbers (ICANN), Internet Assigned Numbers Authority (IANA), Internet Registries (RIR). There are policy and decision makers that provide regulations on cross-border communications, there are international agreements, there are vendors that provide network infrastructure, there are internet users and educators that use the Internet to communicate, teach and build new technologies. My point is that The Internet is not a thing, a company or a product. The internet is a global system of distributed agencies and technical mediation that make possible to link networking devices worldwide.
The Internet Architecture and the Design Principles
After knowing the history and the events that happened, it is important to also try and “de-blackbox” the design principles and the architecture of the Internet. As Irvine explains in his article “The Internet: Design Principles and Extensible Futures”, there are three main design principles that make it possible for us today to use the Internet in different ways: Extensibility, Scalability and Interoperability.
Extensibility has to do with the idea that an implementation can grow, and to extend a system, means to add new functionality and modify parts of the system, without changing the overall behavior of the system.
Scalability is the ability of a program or a system to run effectively, even when it is changed in size or volume.
Interoperability is the ability of a system to exchange/communicate information.
Irvine highlights the Internet as “the mother of all case studies”. The Internet is a modular system, it is a complex socio-technical system, it has cumulative combinatorial design principles, and it has an open architecture.
Modularity is a design principle where the components in a system are highly independent. (Schewick, 2010). This means that there are minimal dependencies among the components of a system. So, you can change certain parts of the modules, without affecting the whole system. This design principle reduces the complexity of a system.
As explained by Schewick, Layering is a special form of Modularity. In a layered system, modules are organized in layers that constrain dependencies between modules. The architecture of the Internet is based on a layering principle called relaxed layering with a portability layer. By basing design on increasing levels of abstraction, layering greatly reduces complexity.
As Irvine suggests, it is somewhat easier to manage the technical layers of how networks are connected, since it is a complex but manageable engineering problem, but, on the other hand, it is much harder to understand the international political-economical issues between different countries, conflicts in ownership of network infrastructure, agreements on standards and control of content. Exactly these issues, make the Internet a complex socio-technical system.
The Internet was built and designed in an open environment, where different communities, researchers from all over the world designed and worked on the prototype. This was made possible because the architecture of the Internet has come to be called “open architecture“. Ronda Hauben, in her paper “Encyclopedia of Computers and Computer History” explains the definition of what an open-architecture means:
“Open architecture…describes the structure of the Internet, which is built on standard
interfaces, protocols, a basic data format, and a uniform identifier or addressing
mechanism. All the information needed regarding the interconnection aspects is publicly
available.In the case of networks, the challenge in designing an open architecture system is
to provide local autonomy, the possibility of interconnecting heterogeneous systems, and
communication across uniform interfaces. Providing a basic format for data and a
common addressing mechanism makes possible data transmission across the boundaries
of dissimilar networks.”
After having an idea about the design principles and the architecture of the Internet, we need to try and understand how different agents are connected and work together in transmitting information. The Internet is a system that includes everything from the cables that carry information, to routers, modem servers, cell phone towers, satellites all interconnected, transmitting information using the Internet Protocols.
When you send e message from your computer to a friend, using the Internet as the mean of this communication, that message is divided into packets/blocks as we saw earlier, it finds different paths from the modem, to the router, finds the Domain Name Server and then the appropriate Web Server using the Internet Protocols, and at this point the message is than reassembled into the packets from the original whole, and that’s how your friend receives that message. There is a trade of complexity and performance that happens while using these design principles, but the end goal of this architecture is to effectively have the flow of information, the transmission of the data packets from one end of the server to the other.
The Internet and the Web
When we use the terms “the Internet”, and “the Web”, we usually refer to the same thing. There is a distinguishment between these two terms, and it is important to know the difference. As explained earlier, the Internet is a a system of interconnected computer networks that use TCP/IP to link networking devices worldwide. On the other hand, the Web is a system of web pages and sites that use the Internet to share their information. It was Tim Berners-Lee that invented the Web in 1989. Tim Berners-Lee, in his paper “Weaving the Web: The Original Design and Ultimative Destiny of the World Wide Web” explains that when he thought of the Web, he envisioned ”a space in which anything could be linked to anything”. He wanted this to be a single,global information space. He explains the idea behind this “space” by saying that every information would be labeled, have an address, and then, by being able to reference this information, the computer could represent association between things, and all this could be an open space for everyone to use and share. Similarly to the Internet, the Web is a protocol layer that works over the architecture of the Internet. The Web is based on different standards and protocols including data standards, network services, HTTP protocols. There are different layers that make up the web architecture.
The Internet that we use today was born as a historical accident and different agents (government research, private research, university research) played significant roles in designing the Internet architecture. ARPA helped in funding the research that was done in creating a new generation of technologies for inter-networking, the concept of packet switching, the development of Transmission Control Protocol and Internet Protocol (TCP/IP), the concept of the “network of networks”. Packet-switching method for data protocols for any computer, provided the solution to one of the main challenges that researchers were trying to solve, and that was designing a network that could allow any kind of computer to exchange data over a common network with no single point of failure. Internet development converged with the PC industry. In the beginning, computers were seen as single artefacts that could perform calculations in a short amount of time. Now, their purpose has changed and evolved, and data network chips are standard equipment in every PC, so they can connect to the network. There were two main dimensions that made the Internet successful. Firstly, its design principles, modular architecture based on open standard and secondly, computer networks are mediators of the larger network of social, political and economical factors. The Internet is a complex socio-technical system, with a cumulative combinatorial design, an open-architecture that uses the design of TCP/IP. To make the global connections possible, there is a whole “Internet ecosystem”that helps in regulating international agreements and standards, so the architecture of the Internet is open and because of that it’s not owned or controlled by a specific group that has dominant powers over the others. There are a lot of debates recently concerning “the future of the internet”, and we are hearing a lot about net neutrality, the issue among corporations who own network infrastructure and those who own access to content and media services. By understanding the design principles and the architecture of the Internet, we can be part of these discussions and we can find ways for all the combinations of different technologies, so the principles of Extensibility, Scalability and Interoperability can help us to be globally connected, in an open environment. That’s why it it important to not think about the Internet as just “a thing” or “magic”. Rather, it is a complex system that we all are part of, and the more we know and understand the history, the design principles, and the architecture, the more we can help to develop and design the future of the Internet.
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