1. Future Research Directions Jennifer Rexford Advanced Computer Networks http://www.cs.princeton.edu/courses/archive/fall08/cos561/ Tuesdays/Thursdays 1:30pm-2:50pm

2. Tussles in Cyberspace

3. Internet Design Based on Common Goals Original design of the Internet –“Hook all the computers in the world together so that as yet unknown applications could be invented to run there.” Today’s reality –“The Internet is not a single happy family of people dedicated to universal packet carriage. There is contention among the players.”

4. Stakeholders With Different Goals Users running applications Commercial providers making money Governments enforcing laws Intellectual property rights holders Malicious parties who want to do harm …

5. Contention (Tussle) Amongst the Parties Single IP address vs. use of NATs Property rights vs. P2P file sharing Government wiretapping vs. encryption Firewalls vs. tunneling, rerouting, port tricks Robust, efficient routes vs. ISP competition End-host congestion control vs. selfish users …

6. Design for Tussle Tussle in the Internet takes place at run time –Not primarily at design time (i.e., IETF) Yet the design affects how tussle plays out –What each component is capable of doing –The boundaries between different components Designing for tussle –Design for choice, for variation in outcome Open interfaces; separation of policy and mechanism –Modularize the system along tussle boundaries Bad: DNS names to name hosts and express trademark Good: ToS bits separate application from service quality

7. Discussion

8. Research Challenges

9. Improve system properties of the Internet –Reliability –Security –Managability –Scalability –Performance Provide new features in the Internet –Mobility and disconnected operation –Interactive applications –Energy efficiency –Innovation inside the network

10. Tension Between Goals Mobility vs. scalability –Location-independent addressing… –… vs. hierarchical addressing tied to routing Reliability vs. affordability –Redundancy and avoiding shared risks… –… vs. co-location of nodes and links Security vs. innovation –Limiting the power of the end system –… vs. programmability for new capabilities Security vs. privacy –Self-certifying identifiers and attribution –… vs. anonymous communication

11. Areas That Interest Me Network management –Protocols and monitoring for ease of management Programmability inside the network –Enabling (rapid) innovation and customization Network virtualization –Parallel virtual networks and new management apps Incremental deployability –Backwards compatibility and economic incentives Rigorous protocol design and analysis –Optimization theory as a way to “derive” protocols Energy efficiency –Green networks and reducing energy at end hosts

12. Areas That Interest You? What topics strike you as most important? What research approaches seem most appropriate? What are your thoughts on the collection of papers we read and discussed?

13. Conclusions Tons of scope for interesting research –Intellectually fascinating in its own right –… and many connections to other disciplines –Practically relevant, with chance for real impact Next and final class –Course project presentations (15 min each) –Thursday January 22 11:30am-1:30pm –Lunch provided!