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Introduction to tussle analysis methodology
Costas Courcoubetis (AUEB)The interplay of economics and technology for the Future InternetSESERV WorkshopAthens, Greece, January 31, 2012
SESERVSocio-Economic Services for European Research Projectshttp://www.seserv.org
European Seventh Framework CSA FP7-2010-ICT-258138
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Internet Technology layer
Internet Socio-Economic layer
ISPsEnd-users ASPsRegulators
Socio-Economic layer is governed by laws of socio-economics, while technology layer by laws of physics
routerslinks switches
Internet protocols
Internet applications
Firewalls
middleboxes
3G towers
Out-of-network socio-economic interactions
Stakeholders with varying socio-economic interests
Technology choices (including investments, configurations)
Technology outputs (connectivity, QoS, mobility, security, etc.)
Technology components
…
servers
The Internet as a Platform for Stakeholders’ Interactions
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Stakeholders’ strategies / policies with respect to a specific technology (functionality)
Adopt technology
Dimension resources
Configure technology
Use technology
ISPLonger
Shorter
Adap
tatio
n tim
esca
le
The combination of actors’ strategies lead to a tussle outcome, characterized by stakeholders benefits.
Internet Socio-Economic layer
tussle outcome
Basic Socio-economic Technology Cycle
Feed
back
At each stage conflicts of interest (incentives) arise at the socio-economic layer.
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Tussle Evolution (1)
• If the tussle outcome is considered “unfair” by certain stakeholders, they can react, and:• leave the system• adopt another technology or reconfigure that used• ask the regulator to intervene
• … thus making the outcome unstable
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Tussle Evolution (2)
• Even a “fair” tussle outcome can destabilize other functionalities spillover effect• Case study: Bandwidth sharing:
• ISPs throttle bandwidth of p2p applications by using DPI• p2p applications perform traffic obfuscation• ISPs apply DPI techniques to affect quality of rival VoIP
services
• Analyzing the anticipated tussles can predict unstable periods • and help the long-term success of a technology
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Step 1: Identify all primary stakeholder roles and their characteristics for the functionality under investigation
Step 3: For each tussle assess the impact to each stakeholder and potential spillovers
Functionality I Functionality II
Step 2: Identify tussles among identified stakeholders
spillover new iteration
tussle tussle tussle tussle
A tussle analysis methodology
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Towards achieving stable outcomes• The “Design for choice” principle provides guidance
in designing protocols that allow for variation in outcome. Useful properties are: • “Exposure of list of choices” suggesting that the
stakeholders involved must be given the opportunity to express multiple alternative choices and which the other party should also consider.
• “Exchange of valuation” suggesting that the stakeholders involved should communicate their preferences in regard to the available set of choices (for instance by ranking them in descending order).
• “Exposure of choice’s impact” suggesting that the stakeholders involved should appreciate what the effects of their choices are on others
• “Visibility of choices made” suggesting that both the agent and the principal of an action must allow the inference of which of the available choices has been selected.
Clark, D. D., Wroclawski, J., Sollins, K. R., and Braden, R.: Tussle in Cyberspace: Defining Tomorrow’s Internet. IEEE/ ACM Trans. Networking 13, 3, pp. 462-475, June 2005
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Towards avoiding tussle spillovers to other functionalities
• The “Modularize the design along tussle boundaries” principle helps in identifying whether tussle spillovers can appear.
• A protocol designer can check the following two conditions:• “Stakeholder separation”, or whether the choices of one
stakeholder group have significant side effects on stakeholders of another functionality (another tussle space), for example creates economic externalities between stakeholders of different tussle spaces.
• “Functional separation”, or whether different stakeholders use some functionality of the given technology in an unforeseen way to achieve a different goal in some other tussle space, i.e., the functionality of technology A interferes (and possibly cancels) with functionality of technology B.
Clark, D. D., Wroclawski, J., Sollins, K. R., and Braden, R.: Tussle in Cyberspace: Defining Tomorrow’s Internet. IEEE/ ACM Trans. Networking 13, 3, pp. 462-475, June 2005
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