Distributed Computing
ETH Zurich

Distributed Systems (HS 2021)

Course Catalogue

Note: This course is part of the course "Computer Systems" (252-0217-00L). Visit the page of the full course held together with Professor Roscoe here. The internal moodle link is here.

This course introduces the fundamentals of distributed systems. We study different protocols and algorithms that allow for fault-tolerant operation, and discuss practical systems that implement these techniques. The objective of the course is for students to understand the theoretical principles and practical considerations of distributed systems. This includes the main models of fault-tolerant distributed systems (crash failures, byzantine failures, and selfishness), and the most important algorithms, protocols and impossibility results. By the end of the course, students should be able to reason about various concepts such as consistency, durability, availability, fault tolerance, and replication.

Topics: client-server, serialization, two-phase protocols, three-phase protocols, paxos, two generals problem, crash failures, impossibility of consensus, byzantine failures, agreement, termination, validity, byzantine agreement, king algorithm, asynchronous byzantine agreement, authentication, signatures, reliable and atomic broadcast, eventual consistency, blockchain, cryptocurrencies such as bitcoin and ethereum, proof-of-work, proof-of-*, smart contracts, quorum systems, fault-tolerant protocols such as piChain or pbft, distributed storage, distributed hash tables, physical and logical clocks, causality, selfishness, game theoretic models, mechanism design.

Course pre-requisites: None.

Course language: English.

Lecture by Roger Wattenhofer, Monday or Friday 10.15-12.00 @ CAB G 61. Also on Zoom: Meeting ID: 672 0550 6948, Password: 018029

Videos Videos of the lectures can be found on the ETH Video Portal.

Exercises Friday 14.15-16.00 @ CAB G 57. Exercises only take place in the weeks with a lecture. Also on Zoom: Meeting ID: 649 0249 7237, Password: DustyWires . Recordings of the exercise sessions can be found here.

Bonus See here for description of the bonus task, deadline for submissions, etc.

Organization by Tejaswi Nadahalli and Lukas Bürgi (lukas.buergi@asvz.ch).

Corona information: We will follow Corona guidelines from the main ETH administration. Check here for more details.

Script 2021: You can find the script for 2021 here.

Word of advice from the professor: Instead of attending this course, you can also just read The Saddest Moment by James Mickens, the guy who continuously tried to convince me that having vodka shots at a local Denny's at 3am is how I should spend my nights. Just reading Mickens will not give you any credits though.


21.12.2021Chapter 26: Part 2. Cascade: Only the motivation (section 1) is relevant to the exam. The technical details of the paper are not exam material.
15.12.2021Chapter 24 (Advanced Blockchains): Section 24.2 is not exam material.
23.11.2021Chapter 19 (Consistency & Logical Time): Sections 19.3 and 19.5 are not exam material.

Lecture Material

Lecture material and exercise sheets will be uploaded here as the lecture progresses. Note that chapter numbers are aligned with the course "Computer Systems".

Title Lecture Notes Exercises Additional Material
Chapter 14
Date: 08-November-2021
PDF --- ---
Chapter 15
Fault Tolerance & Paxos
Date: 08-November-2021
PDF --- ---
Chapter 16
Date: 12-November-2021
PDF Exercises
Exercise Slides
Chapter 17
Byzantine Agreement
Date: 15-November-2021
PDF --- ---
Chapter 18
Broadcast & Shared Coins
Date: 19-November-2021
PDF Exercises
Exercise Slides
Chapter 19
Consistency & Logical Time
Date: 22-November-2021
PDF --- ---
Chapter 20
Time, Clocks & GPS
Date: 26-November-2021
PDF Exercises
Exercise Slides
Chapter 21
Quorum Systems
Date: 29-November-2021
PDF --- ---
Chapter 22
Distributed Storage
Date: 03-December-2021
PDF Exercises
Exercise Slides
Chapter 23
Eventual Consistency and Bitcoin
Date: 06-December-2021
PDF --- ---
Chapter 24
Advanced Blockchains
Date: 10-December-2021
PDF Exercises
Exercise Slides
Chapter 25
Game Theory
Date: 13-December-2021
PDF --- ---
Chapter 26
Authenticated Agreement
Date: 17-December-2021
PDF Exercises
Chapter 26: Part 2
Date: 17-December-2021
PDF --- ---
Chapter 27
Advanced Topics in Distributed Systems
Date: 20-December-2021
--- --- Dfinity Internet Computer
Fair Ordering

Exam Preparation

To get an idea for the style of questions in the exam, you may consult exams from previous years: HS09, HS10, HS11, HS12, HS13, HS14, HS15, HS16, HS18, HS19, HS20. Beware that the topics covered have shifted around a little over the years, so some older exams have questions about topics that are not in the lecture anymore. Some of the older exams are in German, but this year’s exam is in English.