Distributed Systems Course (fall 2017/2018)

Passing Rules

To pass the course, a student has to score at least 60 out of a total of 100 points and pass the lab (see below). The points can be scored for:

• lab assignments: up to 50 points
• a written exam at the end of the semester: up to 50 points

The final grade is calculated as follows:

Points	0-51	52-59	60-67	68-75	76-83	84-91	92-...
Grade	2 (fail)	2+ (fail)	3	3+	4	4.5	5

Lab Rules

The goals of the lab are twofold. First, the lab allows each student to build her own simple distributed system. The building process will consist of two assignments and one colloquium. Second, the lab creates an opportunity for the student to update other students with a piece of recent work in the area of distributed systems. This will have the form of an oral presentation.

To pass the lab, each student has to score a total of at least 30 points and a given number of points per each assignment. The detailed breakdown of the scores and deadlines is as follows:

What	When	How many points	Min. required points
Colloquium	October 11, 2017, 16:00 CEST	5	0
Assignment 1	November 22, 2017, 23:59 CET	15	8
Assignment 2	January 3, 2018, 23:59 CET	25	14
Oral Presentation	Individually set date (schedule)	15	8

At the beginning of the course, students may decide if they want to work on the assignments individually or in pairs. No larger groups will be allowed. The decision cannot be changed during the semester (after the colloquium). The lecturer will not regard any conflicts within pairs as circumstances affecting grades. In other words, if you work in a pair, choose your partner well.

Assignment solutions have to be handed in on time by submitting e-mails with topic “[DS2017] Solution X” (where X can be 1 or 2) to the tutor of your group (respectively, Konrad Iwanicki for group 1 and Inga Rüb for group 2). Since the tutors receive an excessive number of e-mails, e-mails with different topics may be ignored. Moreover, each day of delay in submitting a solution results in subtracting 2 points from the scores received for the solution. Normally, the delay must not be more than 7 days, after which an assignment is considered as failed (the student receives 0 points). However, each day a student participates in both a lecture and a lab gives the student one extra day of delay (for this day, the points are not subtracted). No future days during which the student intends to participate will be counted toward the reduction. For students working in pairs, the reduction will be counted as the average of the lectures attended by each of the participants (rounded down if necessary).

It is allowed to talk about your ideas on solving the assignments with your colleagues. It is NOT allowed to show, share, exchange code (in any form) without a prior permission from the lecturer.

A presentation is in turn prepared individually and normally given in English (unless your tutor agrees to a different language) with slides in English. However, if foregin students enroll for the course, all presentations will be required to be given in English. The strict time limit of a single talk is 60 minutes, in case of one presentation per class, or 45 minutes, if there are two presentations during a single class. The presenting student will be interrupted after this period. During the talk, other students are discouraged from asking questions. After the talk, there is a questions-and-answers session, during which the presenter answers question posed by the lecturer and other students. The objective of the questions could be, for instance, to clarify some aspects of the paper or to learn the presenter's opinion on a problem related to the paper.

During her presentation of a paper, a student is obliged to display slides for the paper. As a reminder, they have to be in English. The student has to prepare the slides on her own. If some slides for the paper already exist on the Internet, the concents of those slides can be re-used by the student preparing her own slides only if re-using the contents does not violate any copyrights, especially when the student's presentation is made available online. Moreover, the student has to acknowledge using somebody else's slides. Finally, note that conference slides are typically meant for 20-30 minutes, whereas a lab presentation is 45 or 60 minutes, depending on the available time, as explained above.

Tips:

• Read your paper well in advance to understand it and to later be able to answer other students' questions.
• Practice your talk to fit in the time limit.
• Try to briefly go over the related work cited in the paper as this can give you some valuable input on the problem the paper is solving.
• Try to find any follow-ups on the paper because this can be rewarding as well. Skimming through follow-up papers will help you better understand the topic.
• Ask the presenter questions that, rather than proving the presenter doesn't know something, lead to interesting discussions. You are not awarded points for mean or stupid questions.
• If you have read and understood the presented paper, and if you have practiced your talk, relax during your presentation: you will surely be able to answer all questions.

Exam Rules

The exam covers the lecture topics as well as the students' presentations. It consists of a series of questions. Each question has three subquestions with binary (TRUE/FALSE) answers. A students scores a point for a question only if the answers to all subquestions of the question are correct. Conversely, if an answer to any subquestion of the question is incorrect, no point is given for the entire question. Note that these scoring rules are really demanding (cf. the scores for 2016/2017).

Lecture Topics and Schedule

Since this is still a developing course, this year's lectures will be given mostly based on a book by my PhD adviser and the head of my former research group: Maarten van Steen and Andrew S. Tanenbaum, “Distributed Systems,” CreateSpace Independent Publishing Platform, 3.01 edition (February 1, 2017), 596 pages, ISBN 978-1543057386. Purchasing the book is not mandatory as the lecture slides will be available here. There will be a few lectures with an extra material, though.

Date	Topics	Slides
October 4, 2017	Introduction: definition of distributed system, properties of distributed systems, common types of distributed systems	lecture 01
October 11, 2017	Architectures: architectural styles, system architectures	lecture 02
October 18, 2017	Processes: threads, virtualization, clients & servers, server clusters, code migration	lecture 03
October 25, 2017	Communication: fundamentals, remote procedure call, message-oriented communication, stream-oriented communication, multicast communication	lectures 04-05 (part A and B)
November 8, 2017
November 15, 2017	Naming: basic terms and definitions, flat naming, structured naming, attribute-based naming	lecture 06 (part A and B)
November 22, 2017	Synchronization and Coordination: clock synchronization, logical clocks, total-ordered multicast, causal-ordered multicast, mutual exclusion, positioning of nodes, leader election	lectures 07-08 (part A and B)
November 29, 2017
December 6, 2017	Replication and Consistency (Part I): replica management, continuous consistency, data-centric consistency models, consistency protocols	lecture 09
December 13, 2017	Fault Tolerance (Part I): failure models, failure masking, failure detection, reliable client-server communication, atomic multicast, two-phase commit, three-phase commit, checkpointing, logging, recovery, agreement in faulty systems	lectures 10-11
December 20, 2017
January 10, 2018	Fault Tolerance (Part II): agreement in faulty systems (continued), Paxos	lecture 12
January 17, 2018	Replication and Consistency (Part II): CAP theorem, PACELC, eventual consistency, conflict-free replicated data types, client-centric consistency models	lecture 13
January 24, 2018	FINAL EXAM

Lab Topics and Schedule

The schedule of the lab classes with material relevant to building the distributed system is as follows:

Date	Materials
October 4, 2017	Scenario 01
October 11, 2017	Scenario 02
October 18, 2017	Scenario 03
October 25, 2017	Scenario 04
November 8, 2017	Individual work, assignment grading in spare time
November 15, 2017	Scenario 05
November 22, 2017	Scenario 06
November 29, 2017	Scenario 07
December 6, 2017	Scenario 08
December 13, 2017	Individual work, assignment grading in spare time
December 20, 2017
January 10, 2018
January 17, 2018	Entire lab dedicated to assignment grading
January 24, 2018

Student Presentation Topics and Schedule

The schedule of the students' presentations is as follows:

Group 1 (K. Iwanicki)

Date	Presenter	Topic
October 4, 2017	Konrad Iwanicki	Lab organization and rules. Assignment presentation.
October 11, 2017	Tomasz Knopik	Veselin Raychev, Madanlal Musuvathi, Todd Mytkowicz: “Parallelizing User-Defined Aggregations using Symbolic Execution”
October 18, 2017	Adrian Kral	Charlie Curtsinger, Emery D. Berger: “COZ: Finding Code that Counts with Causal Profiling”
October 25, 2017	Jan Kopanski	Kai-Yuan Hou, Kang G. Shin, Jan-Lung Sung: “Application-Assisted Live Migration of Virtual Machines with Java Applications”
November 8, 2017	Rafal Sadziak	Ki Suh Lee, Han Wang, Hakim Weatherspoon: “PHY Covert Channels: Can you see the Idles?”
	Jacek Lysiak	Aleksandar Dragojević, Dushyanth Narayanan, Orion Hodson, Miguel Castro: “FaRM: Fast Remote Memory”
November 15, 2017	Piotr Zalas	Shoumik Palkar, Chang Lan, Sangjin Han, Keon Jang, Aurojit Panda, Sylvia Ratnasamy, Luigi Rizzo, Scott Shenker: “E2: A Framework for NFV Applications”
November 22, 2017	Kasper Radek	Jelle van den Hooff, David Lazar, Matei Zaharia, Nickolai Zeldovich: “Vuvuzela: Scalable Private Messaging Resistant to Traffic Analysis”
November 29, 2017	Michal Pryt	Jonathan Mace, Ryan Roelke, Rodrigo Fonseca: “Pivot Tracing: Dynamic Causal Monitoring for Distributed Systems”
December 6, 2017	Dominik Murzynowski	Subramanian Muralidhar, Wyatt Lloyd, Sabyasachi Roy, Cory Hill, Ernest Lin, Weiwen Liu, Satadru Pan, Shiva Shankar, Viswanath Sivakumar, Linpeng Tang, Sanjeev Kumar: “f4: Facebook's Warm BLOB Storage System”
December 13, 2017	Adam Soltysik	Jake Wires, Stephen Ingram, Zachary Drudi, Nicholas J. A. Harvey, Andrew Warfield: “Characterizing Storage Workloads with Counter Stacks”
	Mateusz Sokolowski	Chunqiang Tang, Thawan Kooburat, Pradeep Venkatachalam, Akshay Chander, Zhe Wen, Aravind Narayanan, Patrick Dowell, Robert Karl: “Holistic Configuration Management at Facebook”
December 20, 2017	Piotr Ciolkosz	Hongyi Zeng, Shidong Zhang, Fei Ye, Vimalkumar Jeyakumar, Mickey Ju, Junda Liu, Nick McKeown, Amin Vahdat: “Libra: Divide and Conquer to Verify Forwarding Tables in Huge Networks”
	Rafal Koltun	Yang Wang, Manos Kapritsos, Zuocheng Ren, Prince Mahajan, Jeevitha Kirubanandam, Lorenzo Alvisi, Mike Dahlin: “Robustness in the Salus scalable block store”
January 10, 2018	Mikolaj Murasik	Heming Cui, Rui Gu, Cheng Liu, Tianyu Chen, Junfeng Yang: “Paxos Made Transparent”
	Filip Czaplicki	Abhishek Verma, Luis David Pedrosa, and Madhukar Korupolu, David Oppenheimer, Eric Tune, John Wilkes: “Large scale cluster management at Google with Borg”
January 17, 2018	Bartlomiej Bancerek	Haonan Lu, Kaushik Veeraraghavan, Philippe Ajoux, Jim Hunt, Yee Jiun Song, Wendy Tobagus, Sanjeev Kumar, Wyatt Lloyd: “Existential Consistency: Measuring and Understanding Consistency at Facebook”
		Chao Xie, Chunzhi Su, Manos Kapritsos, Yang Wang, Navid Yaghmazadeh, Lorenzo Alvisi, Prince Mahajan: “Salt: Combining ACID and BASE in a Distributed Database”
January 24, 2018	No presentations: grading Assignment 2

Group 2 (I. Rüb)

Date	Presenter	Topic
October 4, 2017	Inga Rüb	Lab organization and rules. Assignment presentation.
October 11, 2017	Stanisław Dobrowolski	Veselin Raychev, Madanlal Musuvathi, Todd Mytkowicz: “Parallelizing User-Defined Aggregations using Symbolic Execution”
October 18, 2017	Daniel Gutowski	Charlie Curtsinger, Emery D. Berger: “COZ: Finding Code that Counts with Causal Profiling”
October 25, 2017	Pauló Máté	Kai-Yuan Hou, Kang G. Shin, Jan-Lung Sung: “Application-Assisted Live Migration of Virtual Machines with Java Applications”
November 8, 2017	Mateusz Walkiewicz	Ki Suh Lee, Han Wang, Hakim Weatherspoon: “PHY Covert Channels: Can you see the Idles?”
	Piotr Wiśniewski	Aleksandar Dragojević, Dushyanth Narayanan, Orion Hodson, Miguel Castro: “FaRM: Fast Remote Memory”
November 15, 2017	Paruyr Muradyan	Shoumik Palkar, Chang Lan, Sangjin Han, Keon Jang, Aurojit Panda, Sylvia Ratnasamy, Luigi Rizzo, Scott Shenker: “E2: A Framework for NFV Applications”
November 22, 2017	-	Jelle van den Hooff, David Lazar, Matei Zaharia, Nickolai Zeldovich: “Vuvuzela: Scalable Private Messaging Resistant to Traffic Analysis”
November 29, 2017	-	Jonathan Mace, Ryan Roelke, Rodrigo Fonseca: “Pivot Tracing: Dynamic Causal Monitoring for Distributed Systems”
December 6, 2017	Paweł Goliński	Subramanian Muralidhar, Wyatt Lloyd, Sabyasachi Roy, Cory Hill, Ernest Lin, Weiwen Liu, Satadru Pan, Shiva Shankar, Viswanath Sivakumar, Linpeng Tang, Sanjeev Kumar: “f4: Facebook's Warm BLOB Storage System”
December 13, 2017	Jacek Maksymowicz	Jake Wires, Stephen Ingram, Zachary Drudi, Nicholas J. A. Harvey, Andrew Warfield: “Characterizing Storage Workloads with Counter Stacks”
	Michał Waszczuk	Chunqiang Tang, Thawan Kooburat, Pradeep Venkatachalam, Akshay Chander, Zhe Wen, Aravind Narayanan, Patrick Dowell, Robert Karl: “Holistic Configuration Management at Facebook”
December 20, 2017	Filip Stefaniuk	Hongyi Zeng, Shidong Zhang, Fei Ye, Vimalkumar Jeyakumar, Mickey Ju, Junda Liu, Nick McKeown, Amin Vahdat: “Libra: Divide and Conquer to Verify Forwarding Tables in Huge Networks”
	Stanisław Barzowski	Yang Wang, Manos Kapritsos, Zuocheng Ren, Prince Mahajan, Jeevitha Kirubanandam, Lorenzo Alvisi, Mike Dahlin: “Robustness in the Salus scalable block store”
January 10, 2018	-	Heming Cui, Rui Gu, Cheng Liu, Tianyu Chen, Junfeng Yang: “Paxos Made Transparent”
	Piotr Padlewski	Abhishek Verma, Luis David Pedrosa, and Madhukar Korupolu, David Oppenheimer, Eric Tune, John Wilkes: “Large scale cluster management at Google with Borg”
January 17, 2018	Michał Graczykowski	Haonan Lu, Kaushik Veeraraghavan, Philippe Ajoux, Jim Hunt, Yee Jiun Song, Wendy Tobagus, Sanjeev Kumar, Wyatt Lloyd: “Existential Consistency: Measuring and Understanding Consistency at Facebook”
	Stanisław Mączka	Chao Xie, Chunzhi Su, Manos Kapritsos, Yang Wang, Navid Yaghmazadeh, Lorenzo Alvisi, Prince Mahajan: “Salt: Combining ACID and BASE in a Distributed Database”
January 24, 2018	No presentations: grading Assignment 2

Past Exams

Below, you can find the questions from past exams:

Year	Exam Set	Participants			Points
		Course	Exam	%	Available	Min	Avg	Med	Max
2016/2017	Final (test)	20	15	75.0	25	7	13.13	13	20
2015/2016	Final (test)	16	13	81.3	25	4	10.08	10	22
2014/2015	Final (test)	17	17	100	25	5	12.76	13	20
2013/2014	Final (test)	16	16	100	25	11	14.69	13	21
2012/2013	Final (test)	34	34	100	25	3	10.33	10	22
2011/2012	Final	36	34	94.4	50	10	29.85	30.5	49
2010/2011	Part II	26	21	80.8	25	3.75	16.27	13.5	24.25
2010/2011	Late Part I	26	11	42.3	25	13.75	21.6	21.25	24.75
2010/2011	Early Part I	26	17	65.4	25	9.25	14.9	13.5	22