1. Tussle in cyberspace: Defining tomorrow’s internet D.Clark, J.Wroclawski, K.Sollins, R.Braden Presenter: Baoning Wu

2. Why? Different Internet holders have interests that may be adverse to each other, and they vie to favor their particular interests. This is called TUSSLE. Accommodating this tussle is crucial to the evolution of the network’s technical architecture.

3. Structure of this paper Difference between the mechanisms and society. Outline some proposed design principles Discussion of some tussle space

4. Natures of engineering and society Engineers: solve the problems by designing mechanisms with predictable consequences. Society: dynamic management of evolving and conflicting interests.

5. Internet landscape Users Commercial ISPs Private sector network providers Governments Intellectual property rights holders Providers of content and higher level services

6. Principles Highest-level: design for variation in outcome Two specific principles: –Modularize the design along tussle boundaries –Design for choice

7. Implications from principles Choice often requires open interfaces Tussles often happen across interfaces It matters if the consequence of choice is visible Tussles have different flavors Tussles evolve over time No such thing as value-neutral design Don’t assume that you design the answer

8. Tussle spaces (1) Economics –Providers tussles as they compete and consumers tussle with providers to get the service they want at a low price –Our principle of design of choice into mechanism is the building block of competition

9. Examples Provider lock-in from IP addressing –To incorporate mechanisms that make it easy for a host to change address Value pricing –No value-neutral design: tunneling is good for consumers

10. Examples (continue) Residential broadband access –Municipal deployment of fiber as a platform for competitors Competitive wide area access –Support source routing with a recognition of the need for payment

11. Tussle spaces (2) Trust –Many users do not trust each other. –Do not trust many of the parties they actually want to talk to –Less and less trust the software they have to run –So “design for choice” here

12. Tussle space (3) Openness –The openness to innovation that permits a new application to be deployed –Separate the tussle of vertical integration from the desire to sustain innovation

13. Old principles End to end arguments –Still valid, but need a more complex articulation Separation of policy and mechanism –No pure separation of policy from mechanism, –But is kind of isolation

14. conclusion Do not deny the reality of the tussle, but recognize our power to shape it.

15. Questions?