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Staff
Instructor
Fabián E. Bustamante
Seely Mudd 3509
Email: fabianb@cs...
Location and Time
- Lectures: Tue/Thu 11:00–12:20 — TBD
- Professor Office Hours: By appointment
Note: Session dates will be confirmed once the Fall 2026 Northwestern academic calendar is published. The paper list is final.
About This Course
CS 440 asks: what are the hard design problems in networking, and what does the research frontier look like? The lens is systems design — protocols, architectures, tradeoffs, and implementation choices that make real networks work at scale. Papers are drawn from SIGCOMM, NSDI, CoNEXT, and NINeS. The project asks you to reproduce a published systems result and write a structured critique of the original paper’s claims.
CS 440 pairs with CS 445 (Internet-Scale Experimentation), which focuses on measurement methodology. CS 440 asks what we should build; CS 445 asks what is actually out there. You can take them in either order after CS 340.
A note on NINeS. This edition includes papers from the inaugural NINeS (New Ideas in Networked Systems, 2026), a new highly selective conference that favors bold new ideas and fundamental open questions. All accepted paper talks are freely available online.
Course Prerequisites
The course assumes a basic understanding of topics in networking, such as packet-switching, routing, socket programming, and congestion control, as covered in CS 340 “Introduction to Computer Networking”.
If you have taken a similar course somewhere else, please contact me.
Topics
- Network design principles and architecture
- Internet routing and BGP
- Software-defined networks and programmable infrastructure
- Traffic engineering and WAN design
- Congestion control — theory, signals, and practice
- Transport protocols (TCP, QUIC, RDMA)
- Datacenter networking and topology
- ML training networks
- Naming and DNS infrastructure
- LEO satellites and new access infrastructure
- Video QoE and real-time communication
- Mobile and wireless systems design
- Anonymity and privacy infrastructure
- BGP security and routing integrity
- CDN architecture and Internet infrastructure
Course Organization
Most class meetings are centered on one research topic. Each session pairs a background paper — usually a foundational or classic work — with a recent research paper. Every student is responsible for one to two conference-style presentations during the quarter. You must submit a reading blog post on the research paper before each class.
Grading
| Component | Weight |
|---|---|
| Reading blog | 15% |
| In-class participation | 15% |
| Paper presentation | 20% |
| Reproduction project | 50% |
Academic Integrity
All work submitted must be your own. Blog posts may not be written collaboratively. For the reproduction project, teams may discuss ideas with other teams, but all writing and implementation must be the team’s own work. Any use of AI writing tools must be disclosed.
Accessibility
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 Services for Students with Disabilities (SSD) at +1 847 467-5530 or ssd@northwestern.edu. SSD is located in the basement of Scott Hall. Additionally, I am available to discuss disability-related needs during office hours or by appointment.