This exam is worth 20% of your course grade. Since the exam is take-home, late exams will not be
accepted. All exams must be turned in on Blackboard before the due date.
From the list of topics, pick three (3). For each, produce a well-written, single-spaced, short essay.
In order to receive any credit for the topic, it must be no shorter than seven (7) paragraphs, each
consisting (at a minimum) of five (5) sentences.

For each, write the essay as if you are writing a small sub-section of the textbook based on the
topic. I will be grading your essay not just on the aforementioned quantity, but also on the quality
of your writing (rubric below). In any field, it’s important to be able to produce well-written papers.
It should not have to be said that any form of plagiarism will result in a zero. You are to
work alone on these essays, and you are required to provide a list of the references. The “type” of
citation (e.g., IEEE, MLA) is not important to me, just make sure that there is no confusion as
to what (citation) and where (source) you’re taking things from. If you use Wikipedia as a source,
make sure that it’s not your only source, and that you fact-check it carefully.
Please combine your essays into a single document (text, Word or PDF), with a section header at
the beginning of each short essay. You may combine all of your references into a single section at
the end.

Each of the essays will be graded according to the following rubric:
Meets appropriate length guidelines 20%
Organizational structure (introduction, supporting points, conclusion) 25%
Content is relevant, accurate, and well-written 50%
Proper citation is provided 5%

Topics:
1. Explain the motivation behind a VFS (Virtual File System). Be sure and speak on what they
are, why they exist, and what problems they solve (introduce?). Don’t forget to pay mention
as to where, as far as layers go, the VFS abstraction falls. Pick your favorite operating system
and discuss whether or not it implements a VFS.

2. Discuss the concepts and motivation behind performing system backups. In particular, be sure
and explain the similarities and differences between physical versus logical backups (blockversus
file-level). Moreover, research and explain a few techniques for ensuring the accuracy
and consistency of both types of backups.

3. Summarize the following RAID levels (0, 1, 5, 6, 5+0, 6+0). The last two will potentially
require a little bit of outside research. Be sure and touch on the performance and resilience
(e.g., how many drives can be lost at any given point in time) of each level. Lastly, it is
generally held that RAID isn’t a backup strategy, explain why.

4. Explain, at a high-level, the architecture of VDI (Virtual Desktop Infrastructure). Be sure a
give mention to each of the main components and their roles. Give mention to at least three
(3) pros and cons of VDI versus non-VDI desktop infrastructures. This topic may require a
fair amount of external research (hint: “dumb terminals” and thin clients).

5. Pick any two (2) hypervisors. Examples include: vSphere, Xen, KVM, Hyper-V. For each
hypervisor, briefly explain its history and architecture (i.e., is it Type-1 or Type-2, or something
else). Be sure and research which operating systems it supports (from a hypervisor- as
well as guest-perspective). Lastly, briefly explain whether or not the hypervisors which you
picked support checkpointing and migration.

6. One of the trends, as of late, is the return to “containers” (e.g., Docker). Explain how
containers differ from their counterparts (virtual machines) from an architectural point of
view. Provide information on some of the container technologies supported by the “big
three” operating system (Mac, Windows and *NIX).

7. From the perspective of an operating systems architect, speak on the design issues RDMA
(Remote Device Memory Access) imposes on the operating system. Touch on the motivation
for doing RDMA, i.e., which class of problems does it address? Research at least one
technology which supports RDMA and speak briefly on it.

Note: Make sure you follow instructions and also make sure every essay contains paragraphs. Also, make sure that you follow the rubric criteria given above as they are very important. DO NOT PUT THEM ALL IN ONE PAPER, they have to be separate. Time is very important so the papers have to be delivered on time and i am giving one whole week to have them done. A PDF textbook is attached. Thanks.