HW 3

due Oct. 11

Last modified 10/9/99--PR
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This assignment may be completed individually on in pairs (you pick your own partner). Obviously, the discussion is a group activity.


20.3, web supplement on web supplement on how digital communication works; web supplement on shared communication links

Recommended reading (one of the following sets; they cover a lot of the same ground; I prefer the Scientific American articles, but the Ziff-Davis articles have more info about particular products):

Written exercises

  1. Information Archaeology (2 points). As an archivist, you've been given the job of making some old computer records accessible to historians. The data is stored on an ancient (30-year-old) magnetic tape. Miraculously, you still have a tape reader available, the tape doesn't break, and you're able to transfer the files in question to a modern storage device (a hard disk). You know that the files in question contain text, in the English language, but apparently they were encoded in some representation other than ASCII. So, for now, each file is just a pile of bits. Describe what steps you would take to try to discover the representation scheme that was used, and thus recover the English text.
  2. Text E4.2 (1 point)
  3. Text E4.4 (2 points)

  4. [Notes and hints: keep in mind that, for part b, a computer program needs to be able to cause a circle to be displayed on the screen, using only the bits in the representation. What information about a circle would you need to represent in order to make it possible to regenerate it on a screen, with the right size, location, etc? Unlike the next one, this is a question that you *should* think hard about. There are some deep insights to be gained about how different representations make different operations easy or hard.]
  5. Text E4.5 (1 point)

  6. [Notes and hints: you may find table 4.1, from page 114, useful in defining some of these terms. This is a question you should *not* think too hard about. For a, you're identifying the functional components of a networked workstation, and for b you're identifying the hardware that supports each of those components.]

Your Honor... (2 points)

One of the major points of contention in the Microsoft anti-trust trial is whether Microsoft extended its market power in operating systems to try to gain control of the browser market. Microsoft claims that the browser functions of Internet Explorer are now part of the operating system in Windows98, rather than being a separate "application program". Here are some Wired News articles on the topic. Write a 1-2 page memo to the judge, acting as a "friend of the court." Strive to appear objective by summarizing the arguments for and against considering browser functions to be part of the operating system (who benefits from integration? who from separation?). Be sure to start with clear summary definitions of what a browser and an operating system are. Then give your opinion about whether the judge should consider the browser to be a legitimate part of the operating system, or whether he should order Microsoft to separate the functions.

You are encouraged to discuss this with your study group, but you should write up individual memos.

Explanation exercise (2 points)

(Find someone who is not taking this class, and who knows less about computers than you do. It could be a fellow SI student, or a roommate or a friend or relative). Explain how images and sounds are represented as bit strings in computers. As always, include a couple of sentences saying who you talked to, how you explained it, and how the explainee responded.