2023-2024 Sem I

This course introduces cloud infrastructure. Students should feel more comfortable with building cloud services after having done this course.

Course Information

  • Prerequisites: COL331 or equivalent.

    Note: The course includes programming assignments and thus expects proficiency with systems programming and debugging.

  • Credits: 3-0-2
  • Slot: AA, Mondays and Thursdays 2-3:15pm in LH521.
  • TAs:
    • Abhisek Panda: csz202445 AT cse.iitd.ac.in
    • Ravi Ranjan Singh: jcs222659 AT csia.iitd.ac.in
  • Reading material: There is no textbook for the course. Most lectures will link to more reading material. Lecture notes can be found here and here.
  • Acknowledgements: Thanks to Robert T. Morris, MIT and Mythilli Vutukuru, IITB; parts of this course have been inspired by courses made available by them.

Grading criteria

  • 30% labs (programming assignments)
  • 20% project
  • 10% quizzes
  • 20% minor exam
  • 20% major exam

Supporting systems

  • Labs are to be done on Baadal. You will need VPN access to IITD network!
  • Discussions should be done on Piazza.


  • Audit criteria: 40% or more marks in total. 40% or more marks in major+minor exams.
  • Ethics: Please re-read IITD honour code. Cheating will get an F in the course. Why should I not cheat?
  • Late policy: To help you cope with unexpected emergencies, you can hand in your Labs solutions late, but the total amount of lateness summed over all the lab deadlines must not exceed 72 hours. You can divide up your 72 hours among the labs however you like; you don’t have to ask or tell us. You can only use late hours only for Labs.
  • There will be no make up quizzes. We will count the scores from your best (n-1) quizzes where n is the total number of quizzes.

Tentative topics


  • Translate existing programs to distributed system. (Distributed shared memory)
  • Batch computation (MapReduce, Spark), streaming computation (Spark streaming, Flink, Google Dataflow), ML training (Tensorflow)
  • The problem of late data in streaming computation (Millwheel, Google dataflow): watermarks, triggers, windows.
  • Fault tolerance strategies: re-run deterministic idempotent functions (MapReduce, Spark), asynchronous consistent checkpoints (Flink), inconsistent checkpoints (TensorFlow).
  • Straggler mitigation, scalability, locality, etc.


  • PACELC theorem: If partitioned, choose between availability and consistency, else choose between latency and consistency.
  • CP systems:
    • Linearizability. Raft: quorums, leader election.
    • Serializability. Google Spanner: distributed transactions, TrueTime, hybrid logical clocks.
  • AP systems:
    • Amazon dynamo: eventual consistency, hashing, gossip protocols, dotted version vectors, conflict-free replicated data types (CRDTs)
  • Somewhere between CP and AP
    • Google file system
    • Zookeeper
    • RedBlue consistency

Hardware-assisted virtualization:

  • CPU virtualization: KVM, Popek-Goldberg theorem
  • Memory virtualization: 2-d page tables

Disclaimer: Actual course contents may differ slightly depending on student interest. Reach out to the instructor as soon as possible if there is a particular interest in a topic.

Tentative Schedule

Week Monday Thursday Sunday
1 24 Jul
LEC 1: Introduction.
27 Jul
LEC 2: Scalability, Task DAGs, FaaS.
Ch.5 of Introduction to Parallel Computing
2 31 Jul
LEC 3: Struggles with DSM.
3 Aug
LEC 4: MapReduce. Release Lab 1.
3 7 Aug
LEC 5: Spark: Resilient distributed datasets.
10 Aug
LEC 6: TensorFlow operational semantics.
12 Aug
Lab 1 due
4 14 Aug
LEC 7: TensorFlow.
17 Aug
LEC 8: CIEL. Release Lab 2.
5 21 Aug
LEC 9: CIEL. Quiz 1.
24 Aug
LEC 10: Spark streaming.
26 Aug
Lab 2 due
6 28 Aug
LEC 11: Virtual time and global states.
31 Aug
LEC 12: Flink. Quiz 2.
7 4 Sep
Mental health discussion. Release Lab 3.
7 Sep
8 11 Sep
LEC 13: Dataflow model
14 Sep
Mid-term exam
17 Sep
Lab 3 due
9 18 Sep
LEC 14: GFS. Discuss Lab 3
21 Sep
10 25 Sep
LEC 16: Raft. Release Lab 4
27 Sep
Wednesday in-lieu of holiday on 28th
LEC 17: Raft. Release project.
1 Oct
Lab 4 due
11 2 Oct
Semester break
5 Oct
Semester break
12 9 Oct
LEC 18: Zookeeper. Quiz 3.
12 Oct
LEC 19: CRAQ. Dynamo.
13 16 Oct
LEC 20: Dynamo. Release Lab 5.
19 Oct
LEC 21: Dotted version vectors.
14 23 Oct
No class day
26 Oct
29 Oct
Lab 5 due
15 30 Oct
LEC 23: Spanner.
2 Nov
LEC 24: Spanner. Why virtualization? Quiz 4.
15 6 Nov
Project presentations
9 Nov
Project presentations
15 13 Nov
Govardhan Puja
16 Nov
LEC 25: Hardware-assissted virtualization
17 Nov
Project due