Open Root Server Confederation (ORSC) S. Higgs draft-higgs-dns-game-theory-00.txt Higgs Communications, LLC Category: Informational March 2002 Applying Game Theory To The Domain Name Root System 1. Status of this Memo This document is an Internet-Draft and is subject to all provisions of Section 10 of RFC2026 except that the right to produce derivative works is not granted. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html 2. Abstract This paper applies Game Theory and the Nash Equilibrium to the Domain Name Root System. 3. Concepts & Definitions 3.1. Nash Equilibrium The Nash Equilibrium is a set of mixed strategies for finite, noncooperative games of two or more players in which no player can improve his payoff by unilaterally changing strategy. 3.2. Zero-Sum Game A Zero-Sum Game is a game in which players make payments only to each other. One player's loss is the other player's gain, so the total amount of "money" available remains constant. 3.3. Dominant Strategy Let an individual player in a game evaluate separately each of the strategy combinations he may face, and, for each combination, choose from his own strategies the one that gives the best payoff. If the same strategy is chosen for each of the different combinations of strategies the player might face, that strategy is called a "dominant strategy" for that player in that game. 3.4. Dominant Strategy Equilibrium If, in a game, each player has a dominant strategy, and each player plays the dominant strategy, then that combination of (dominant) strategies and the corresponding payoffs are said to constitute the dominant strategy equilibrium for that game. 3.5. The Commons The "commons" is any resource which is shared by a group of people. 4. Overview In Game Theory, a game consists of a set of rules governing a competitive situation in which from two to "n" individuals or groups of individuals choose strategies designed to maximize their own winnings or to minimize their opponent's winnings. The rules specify the possible actions for each player, the amount of information received by each as play progresses, and the amounts won or lost in various situations. Early game theory restricted attention to zero-sum games, that is, to games in which no player can gain except at another's expense. This restriction was overcome by the work of John F. Nash during the early 1950s. Nash mathematically clarified the distinction between cooperative and noncooperative games. In noncooperative games, unlike cooperative ones, no outside authority assures that players stick to the same predetermined rules, and binding agreements are not feasible. Further, he recognized that in noncooperative games there exist sets of optimal strategies (so-called Nash Equilibrium) used by the players in a game such that no player can benefit by unilaterally changing his or her strategy if the strategies of the other players remain unchanged. Because noncooperative games are common in the real world, the discovery revolutionized game theory. Nash also recognized that such an equilibrium solution would also be optimal in cooperative games. He suggested approaching the study of cooperative games via their reduction to noncooperative form and proposed a methodology, called the Nash program, for doing so. Nash also introduced the concept of bargaining, in which two or more players collude to produce a situation where failure to collude would make each of them worse off. 5. The Tragedy of the Commons The DNS Root is an example of an instance of "the tragedy of the commons." The logic of the commons breaks down when resources decline and/or population grows too large. The DNS Root is a common resource available to all domain name holders. Within the DNS Root, .COM users make more intensive use of the common resource that other TLD users, causing the resource to be degraded (in this instance, a lack of available names). Yet the .COM users gain a private advantage by choosing more intensive use of the common resource, at least while the resource is relatively un-degraded. Another example of the private advantage is the automatic appendage of the .COM suffix by the popular web browsers in unresolved domain name searches. The tragedy is that this intensive use leads to the degradation of the resource to the point that all are worse off. This degradation is also identified by the number of domain name disputes and by demands from multiple trademark holders for exclusive use of the same domain name. In general, "the tragedy of the commons" is that all common property resources tend to be overexploited and thus degraded, unless their intensive use is restrained by legal, traditional, or (perhaps) philanthropic institutions. The classical instance is common pastures, on which, according to the theory, each farmer will increase his herds until the pasture is overgrazed and all are impoverished. Thus, we have cases of deliberate destruction of the commons to not only get the wealth out of it before someone else does, but also to leave nothing for others. Often, this has involved the ruin of other commons resources along with the ones sought after. 6. Game Theory On Competing Roots In this scenario we have two actors, both of whom applied to the U.S. Department of Commerce for the role of DNS Root administrator in 1997. The Internet Corporation for Assigned Names and Numbers (ICANN) and the Open Root Server Confederation (ORSC) both started out with identical root zones, which were based upon the root zone of the prior DNS Root administrator, the Internet Assigned Numbers Authority (IANA). ORSC New ORSC TLD Root ----------------- New TLD | 20,20 | 0,10 | ICANN |-------|-------| ICANN Root | 10,0 | 5,5 | ----------------- Figure 1. Game Theory Applied To Root Systems In Figure 1, incentives for an identical non-expansive root are valued at 5 points. When a new TLD, such as a ccTLD, is added to both root systems, pressure is lifted from the DNS and this extension to the name space benefits both root systems, and therefore each receive 20 points. When a TLD is added to one root system and not another, pressure is reduced from one root zone only, and this is valued at 10 points. The ideal situation (20,20), where both organizations win, is for a unified root system in which both root systems cooperate. ORSC .FOO .BAR None ------------------------- .FOO | 20,20 | 10,10 | 10,0 | |-------|-------|-------| ICANN .BAR | 10,10 | 20,20 | 10,0 | |-------|-------|-------| None | 0,10 | 0,10 | 0,0 | ------------------------- Figure 2. Situations With Identical Top Level Domains In Figure 2, incentives for an identical non-expansive root are valued at 0 points (the degradation of the resource is valued at 0 points). When a new TLD, such as a ccTLD, is added to both root systems, pressure is lifted from the DNS and this extension to the name space benefits both root systems, and therefore each receive 20 points. When a TLD is added to one root system and not another, pressure is reduced from one root zone only, and this is valued at 10 points. Again, the ideal situation (20,20), where both organizations win, is for a unified root system in which both root systems cooperate. ORSC .FOO(1) .BAR(1) None ------------------------------- .FOO(2) | -10,-10 | 10,10 | 10,0 | |---------|---------|---------| ICANN .BAR(2) | 10,10 | -10,-10 | 10,0 | |---------|---------|---------| None | 0,10 | 0,10 | 0,0 | ------------------------------- Figure 3. Situations With Colliding Top Level Domains In Figure 3, incentives for an identical non-expansive root are valued at 0 points (the degradation of the resource is valued at 0 points). When a TLD is added to one root system and not another, pressure is reduced from one root zone only, and this is valued at 10 points. When identical, and conflicting TLDs are active in both root zones, because of the confusion and duplication of name space, the value is negative 10 points. In this case, the ideal situation (10,10), where both organizations win, is for each root to only introduce non-conflicting TLDs. 7. Conclusion By applying the Nash Equilibrium to the practical application of the hierarchy and distribution of the DNS, this paper concludes that the spirit of RFC1591 is mathematically valid. RFC1591 states: "The designated manager must be equitable to all groups in the domain that request domain names" and "the principles described here apply recursively to all delegations of the Internet DNS name space." This paper shows that the internet is enhanced by mutual co-ordinated co-operation. Individually rational actions result in both parties being made worse off in terms of their own self-interested purposes. Therefore ICANN cannot be expected to win a zero-sum game. 8. References Nash, J. F. (1950) , Equilibrium Points in N-Person Games, Proceedings of the National Academy of Sciences of the United States of America 36, 48-49. Nash, J. F. (1951), Non-Cooperative Games, Annals of Mathematics 54, 286-295. Nash, J. F. (1950), The Bargaining Problem, Econometrica 18, 155-162. Nash, J. F. (1953), Two Person Cooperative Games, Econometrica 21, 128-140. McCain, R. A. Game Theory: An Introductory Sketch Postel, J., RFC1591, Domain Name System Structure and Delegation 9. Author Simon Higgs Higgs Communications, LLC P.O. Box 4519 Sunland CA 91041-4519 simon@dns-root.org ###