1. Networking Research Nick Feamster CS 7001

2. Nick Feamster Ph.D. from MIT, Post-doc at Princeton this fall Arriving January 2006 –Here off-and-on until then. Email works well. Likely teaching CS 7260 in Spring 2005 Research Interest: Networked Systems feamster@cc.gatech.edu feamster@cc.gatech.edu http://www.cc.gatech.edu/~feamster/

3. Design of Large, Networked Systems Distributed systems with independent, competing entities driven by self-interest Must cooperate to provide service Internet routing, peer-to-peer systems, federated computing infrastructures,…

4. Why work in networking? A chance to apply many different tools –Theoretical foundations –Statistics, machine learning, signal processing, data mining, etc. A chance to build cool systems –Real, working systems that people want and need –Solving real problems (network management, anti-censorship, fighting spam, etc.) A chance to measure and explore –Internet measurement puts the science in computer science Its a lot of fun!

5. Areas of Focus Network Security –How to guarantee where traffic will or wont go? –How to counter Web censorship and surveillance? –What techniques are spammers using? Network Management and Troubleshooting –How can operators tell when theyve made mistakes? –How to mine large datasets (e.g., traffic, routes, etc.) Networking and Economics –How do selfish users affect traffic patterns? –How to improve connectivity at the network edge?

6. Why Interesting? The Internet is increasingly becoming part of the mission-critical Infrastructure (think public utilities). Big problem: Very poor understanding of how to manage it.

7. Why Difficult? Large-scale: Thousands of autonomous systems Self-interest: Independent economic and performance objectives Comcast Abilene AT&T Level3 Georgia Tech The Internet

8. Today: Reactive Operation Problems cause downtime Problems often not immediately apparent What happens if I tweak this policy…? ConfigureObserve Wait for Next Problem Desired Effect? Revert No Yes

9. Catastrophic Configuration Faults …a glitch at a small ISP… triggered a major outage in Internet access across the country. The problem started when MAI Network Services...passed bad router information from one of its customers onto Sprint. -- news.com, April 25, 1997 Microsoft's websites were offline for up to 23 hours...because of a [router] misconfiguration…it took nearly a day to determine what was wrong and undo the changes. -- wired.com, January 25, 2001 WorldCom Inc…suffered a widespread outage on its Internet backbone that affected roughly 20 percent of its U.S. customer base. The network problems…affected millions of computer users worldwide. A spokeswoman attributed the outage to "a route table issue." -- cnn.com, October 3, 2002 "A number of Covad customers went out from 5pm today due to, supposedly, a DDOS (distributed denial of service attack) on a key Level3 data center, which later was described as a route leak (misconfiguration). -- dslreports.com, February 23, 2004

10. Theory: Correctness Specification Path Visibility Every destination with a usable path has a route advertisement Route Validity Every route advertisement corresponds to a usable path Safety The protocol converges to a stable path assignment for every possible initial state and message ordering Example violation: Network partition Example violation: Routing loop If there exists a path, then there exists a route If there exists a route, then there exists a path The protocol does not oscillate

11. Used by operators of many ASes http://nms.csail.mit.edu/rcc/ Practice: rcc PreprocessorParser Verifier Distributed router configurations Relational Database (mySQL) Constraints Faults (Cisco, Avici, Juniper, Procket, etc.) Feamster & Balakrishnan, Detecting BGP Configuration Faults with Static Analysis, NSDI 2005

12. Design: Routing Control Platform iBGP RCP After: RCP gets best iBGP routes (and IGP topology) iBGP eBGP Before: conventional iBGP Feamster et al., The Case for Separating Routing from Routers, SIGCOMM FDNA, 2004 Caesar et al., Design and Implementation of a Routing Control Platform, NSDI, 2005

13. What is it like to work with me? Measure Model Design and Implement Bottom-up, with an eye towards deriving principles that are useful for work on top-down designs of systems. Systems with a strong theoretical foundation.

14. What might we work on together? Mini-projects Conference Papers –Internet measurement –Internet security (design and measurement) –Network management –Incentives and network economics Something coming from these general research interests of your own devising

15. Some High-Level Questions Security: How to protect a global system like the Internet from individual bad actors? Measurement: How to develop a platform for repeatable network experimentation? Design: How to implement, test, and deploy new routing protocols and architectures? Economics/Measurement: How to balance end-to-end performance requirements with autonomy of each network?