1. Tussle in cyberspace: Defining tomorrow ’ s internet D.Clark, J.Wroclawski, K.Sollins & R.Braden Presented by: Ao-Jan Su (Slides in courtesy of: Baoning Wu)

2. Introduction 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. Tussle Examples The different players –Music lovers vs. the rights holders –People who want to talk in private vs. the government that want to tap their conversation –ISPs must interconnect but are sometimes fierce competitors New requirements on the internet’s technical architecture –Motivate new design strategies to accommodate the growing tussle

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

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

6. Internet landscape Users Commercial ISPs Private sector network providers Governments Intellectual property rights holders Content providers and higher level services

7. Principles Highest-level: design for variation in outcome -- Be flexible Two specific principles: Modularize the design along tussle boundaries Use modularity to manage complexity Design for choice Users ’ choice of mail systems

8. Implications from principles Choice often requires open interfaces Allow competition among algorithms Tussles often happen across interfaces Example: BGP connects competitive ISPs It matters if the consequence of choice is visible Public vs. secret (routing arrangement among ISPs) Tussles have different flavors Different interests (sender & traffic carrier)  pricing problem

9. Implications from principles (Cont.) Tussles evolve over time It is a multi-round game No such thing as value-neutral design No perfect design decisions. Don ’ t assume that you design the answer You are designing a playing field, not the outcome.

10. 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 Customers must have the ability to choose (switch) providers freely.

11. Examples Provider lock-in from IP addressing Incorporate mechanisms that make it easy for a host to change address Change you cell phone carrier without changing your cell phone number Value pricing Divide customers based on their willingness to pay Pay higher rate to run a server at home

12. 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 Pay toll

13. Tussle spaces (2) Trust Users do not trust each other. Users don ’ t trust parties they actually want to talk to Less and less trust to their own software “ Not permitted is forbidden ” or “ Not forbidden is permitted ” Design for choice: privacy vs. security

14. Tussle space (3) Openness The openness to innovation that permits a new application to be deployed Vertical integration Are you willing to pay more for ISPs with QoS?

15. Old principles End to end arguments Still valid, but need a more complex articulation Network could provide more information (ECN, QoS) Separation of policy and mechanism Mechanism defines the range of “ policies ” No pure separation of policy from mechanism.

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

17. Questions?