Read "The Design Philosophy of the DARPA Internet Protocols" by Dave Clark. Although the copy of the paper that we're using is from 2013, and includes in-line commentary from Dave Clark, the original paper was written in 1988, before the Internet was commercialized. (Prior to commercialization, the NSF controlled most of the Internet the primary routes that make up the Internet. In the early nineties, they sold their assets, which allowed private corporations to gain control. As a result—of this, and of a few other things—it became easier to do business on the Internet.)

The paper starts by introducing the goals of the Internet's architecture (Sections 1-3). It then dives into the details of some of these goals (Sections 4-7) before discussing implementation details and concluding.

As you read, you should think about:

  • Why did the Internet architects decide to divide TCP and IP into two separate protocols?
  • How do datagrams help the Internet achieve two of its goals: to connect existing networks and to survive transient failures?
  • If you could start from scratch, how would you redesign the Internet today? Would you keep the same principles but change their order? Would you use new principles?

Question for Recitation

Before you come to this recitation, you'll turn in a brief answer to the following questions (really—we don't need more than a sentence or so for each question). Your TA will be in touch about exactly how to turn that in.

Your answers to these questions should be in your own words, not direct quotations from the paper.

  • What were three of the most important goals of the early Internet?
  • How was it designed to meet those goals?
  • If you could go back in time and redesign the Internet, what goals would you prioritze? Why?
As always, there are multiple correct answers for each of these questions.


Supplemental notes for this recitation. These, along with our Sunday office hours are intended to help students who had to miss a recitation due to isolation, but they're also a useful resource for preparing for exams. [an error occurred while processing this directive]