EECS-345 Distributed Systems, Spring 2016


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Administrative Information


Fabián E. Bustamante
Technological Institute, L477
+1 847 491-2745
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Zach Bischof
Ford Design Building, 2-208
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Location and Time

Lectures: Mondays and Wednesdays 11:00-12:20PM
Tech. L150

Professor Office Hours: by appointment

TA Office Hours: Wednesdays 4-6 in office or adjacent lounge

Final Exam: Monday June 6, 3-5PM
(in the classroom)

Course Description

Distributed systems are collections of networked computers that coordinate their actions through message exchanges. Most computing systems you interact with everyday are indeed distributed (e.g. email, web, Google, Skype, Facebook ...) for a variety of reasons such as fault tolerance, performance, and the geographical nature of the requirements.

In this course, we will discuss some of the basic principles behind distributed systems as well as common approaches and techniques used to build them. We illustrate these ideas through case studies of widely used or seminal systems.

In compliance with Section 504 of the 1973 Rehabilitation Act and the Americans with Disabilities Act, Northwestern University is committed to providing equal access to all programming. Students with disabilities seeking accommodations are encouraged to contact the office of Services for Students with Disabilities (SSD) at +1 847 467-5530 or This email address is being protected from spambots. You need JavaScript enabled to view it. . SSD is located in the basement of Scott Hall. Additionally, I am available to discuss disability-related needs during office hours or by appointment.

Course Prerequisites

Communication Channels

There are a number of communication channels set up for this class:

  • We will use the course web site to post announcements related to the course. You should check this regularly for schedule changes, clarifications and corrections to assignments, and other course-related announcements.
  • We will use Piazza for class discussion. The system is highly catered to getting you help fast and efficiently from classmates, the TA, and myself. Rather than emailing questions to the teaching staff, I encourage you to post your questions on our Piazza for DS
  • There is always email for questions that would be inappropriate to post on the newsgroup/discussion-board. When using email to contact the staff please start your subject line with "eecs345: helpful-comment" to ensure a prompt response.

Course Organization

The course is organized as a series of lecture and paper discussions, four projects and a take home exam.

  • Lectures - A set of lectures on the core of the material. At the end of some key topics we will have one student lead presentation of a closely related, somewhat recent research.
  • Readings - Textbook and paper reading in preparation for (not substitution of) the lecture.
  • Homework assignments - A set of assignments meant as reader enforcers.
  • Projects - Four programming projects to give you a better understanding of the subject matter and experience with the Go programming language.
  • A final exam.


I use a criterion-referenced method to assign your grade; in other words, your grade will be based on how well you do relative to predetermined performance levels, instead of in comparison with the rest of the class. Thus, if a test has 100 possible points, anyone with a score of 90 or greater will get an A, those with scores of 80 or greater will get a B, those with scores of 70 or greater will get a C, and so on. Notice that this means that if everyone works hard and gets >90, everyone gets an A.

Total scores (between 0 and 100) will be determined, roughly, as follows:

  • Homework assignments 15% (+5% extra paper-related questions)
  • Class participation 10%
  • Projects 50%
  • Exam 25% (+5% extra on paper-relatex questions)


Late policy:

Unless otherwise indicated, homework assignments and projects are due by midnight on their due date. If you hand in an assignment late, we will take off 10% for each day (or portion thereof) it is late. Assignments that are three or more days late receive no credit.

Cheating vs. Collaboration:

Collaboration is a really good thing and we encourage it. On the other hand, cheating is considered a very serious offense. When in doubt, remember that it's OK to meet with colleagues, study for exams together, and discuss assignments with them. However, what you turn in must be your own (or for group projects, your group's own) work. Copying code, solution sets, etc. from other people or any other sources is strictly prohibited.


  • Introduction
  • Networking and Internetworking
  • Remote invocation and indirect communication
  • Overlay networks and P2P
  • Distributed file systems
  • Name services
  • Time and global state
  • Coordination and agreement
  • Consistency and replication
  • Mobile distributed systems

The following is our intended calendar with topics, slides (as they become available) and reference material. Note "CDKB5 #" refers to chapters of the class' textbook (Coulouris et al., Distributed Systems: Concepts and Design, 2012). Also, papers tagged as [Q] may be part of homework assignment/finals questions for extra credit.

Week Date Topic
1 3/29 Introduction [pdf]


3/30 Go, Go [pdf] [tutorial.tgz]


2 4/4 Networking and Internetworking I [pdf]


4/6 Networking and Internetworking II [pdf]


3 4/11 Communication I [pdf]


4/13 Communication II [pdf]


4 4/18 Overlay Networks [pdf]


4/19 Distributed File Systems [pdf]


5 4/25 Distributed File Systems [pdf]


4/27 No class; at the Greater Chicago Systems Area Research Workshop (GCASR)
(it's free, consider attending it too!)
6 5/2 Name Services [pdf]


5/4 Content distribution networks [pdf]


7 5/9 Time and Synchronization [pdf]


5/11 Coordination I [pdf]


8 5/16 Global State [pdf]


5/18 Coordination II [pdf]


9 5/23 Consensus [pdf]


5/25 Replication and Fault Tolerance [pdf]


10 5/30 Memorial Day
6/1 Mobile and Ubiquitous [pdf]


* 6/6 Final (3-5PM)


There are some basic homework assignments, mostly meant as reading eforcers, and warmup project and three team projects that build on each other.

In addition, groups of 4-5 students (assigned by the instructors) will work to do a presentation and prepare educational material around on one of the 7-8 papers assigned by the instructors. The material, to be shared with the rest of the class, will include a summary, presentation slides, and a homework assignment and/or demo.

1: Introduction - Overlays 04/15 04/22
2: Distributed file systems - Content distribution 05/03 05/10
3: Time, Coordination and Global Snapshot 05/26 06/02
4: Consensus - Replication 06/01 06/06


The first project for this course is a short, one-week long project meant to serve as a gentle introduction to Go and a quick way to check if you are ready to take on the rest. The following three projects are to be done in teams of 2-3 students (3 is the preferred number, 1 is not allowed), to implement a basic DHT (Distributed Hash Table) and build upon it in some interesting way.

All projects will be done in Go, a language that was originally created within Google, but is now a fully open-source project. Go is garbage-collected and has built-in coroutines (called goroutines) and channels, making it highly suited to building distributed systems. Its standard library is already pretty comprehensive. For example, take a look at the net and rpc packages.

Project 0: NU Chitter 03/31 04/07
Project 1: Kademlia DHT Part 1 04/15 04/25
Project 2: Kademlia DHT Part 2 05/06 05/17
Project 3: Vanish 05/20 06/02

Reading Papers

We will be reading two or more paper per week; you should have read the assigned paper before coming to lecture.

When reading papers it is useful to write down a summary of about a page. Your summary should include at least:

  1. Paper title and its author(s).
  2. Brief one-line summary.
  3. A paragraph of the most important ideas: perhaps a combination of their motivations, observations, interesting parts of the design, or clever parts of their implementation.
  4. A paragraph of the largest flaws; maybe an experiment was poorly designed or the main idea had a narrow scope or applicability. Being able to assess weaknesses as well as strengths is an important skill for this course and beyond.
  5. A last paragraph where you state the relevance of the ideas today, potential future research suggested by the article, etc.

You may find the following documents useful:



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