Distributed Systems

Short write-ups, intuitions mostly from studying/teaching the distributed systems course (CS 425) at UIUC.

• On Liveness

  Clarifying misconceptions about liveness in distributed systems.

• Chandy-Lamport Snapshots

  An intuitive bank-branch example explaining what the Chandy-Lamport Snapshot algorithm does, why local snapshots alone aren’t enough, and how “consistent cuts” capture the full system state.

• Flavours of Consensus: Sync, Async and Byzantine

  Consensus in synchronous, asynchronous and Byzantine settings.

• Power of the RPC Abstraction

  Why RPCs matter? Appreaciating the abstraction of RPCs.

• Design Thumbrules

  Common rules of thumb for distributed systems design

• AWS Outage of October 2025

  Thoughts on the major AWS DNS outage: the race condition, why the setup was fragile, and open design questions.