Crowd computing as a cooperation problem: an evolutionary approach

Cooperation is one of the socio-economic issues that has received more attention from the physics community. The problem has been mostly considered by studying games such as the Prisoner's Dilemma or the Public Goods Game. Here, we take a step forward by studying cooperation in the context of crowd computing. We introduce a model loosely based on Principal-agent theory in which people (workers) contribute to the solution of a distributed problem by computing answers and reporting to the problem proposer (master). To go beyond classical approaches involving the concept of Nash equilibrium, we work on an evolutionary framework in which both the master and the workers update their behavior through reinforcement learning. Using a Markov chain approach, we show theoretically that under certain----not very restrictive-conditions, the master can ensure the reliability of the answer resulting of the process. Then, we study the model by numerical simulations, finding that convergence, meaning that the system reaches a point in which it always produces reliable answers, may in general be much faster than the upper bounds given by the theoretical calculation. We also discuss the effects of the master's level of tolerance to defectors, about which the theory does not provide information. The discussion shows that the system works even with very large tolerances. We conclude with a discussion of our results and possible directions to carry this research further.This work is supported by the Cyprus Research Promotion Foundation grant TE/HPO/0609(BE)/05, the National Science Foundation (CCF-0937829, CCF-1114930), Comunidad de Madrid grant S2009TIC-1692 and MODELICO-CM, Spanish MOSAICO, PRODIEVO and RESINEE grants and MICINN grant TEC2011-29688-C02-01, and National Natural Science Foundation of China grant 61020106002.Publicad

Trustless grid computing in ConCert

Abstract. We believe that fundamental to the establishment of a grid computing framework where all (not just large organizations) are able to effectively tap into the resources available on the global network is the establishment of trust between grid application developers and resource donors. Resource donors must be able to trust that their security, safety, and privacy policies will be respected by programs that use their systems. In this paper, we present a novel solution based on the notion of certified code that upholds safety, security, and privacy policies by examining intrinsic properties of code. Certified code complements authentication and provides a foundation for a safe, secure, and efficient framework that executes native code. We describe the implementation of such a framework known as the ConCert software. 1 Introduction In recent years, numerous organizations have been vying for donated resources for their grid applications. Potential resource donors are inundated with worthwhile grid projects such as discovering a cure for AIDS, finding large prime numbers, and searching for extraterrestrial intelligence. Part of the difficulty in obtaining resources is establishing trust between the grid application developer and the resource donors. Because resource donors often receive little or no direct reward for their contributions, they demand assurances of safety, security, and privacy to protect themselves from malicious as well as simply unreliable software. In an ideal grid framework, as proposed in Legion [18], users are provided the abstraction of a single virtual machine that automatically distributes work and gathers results. In such a framework, this issue is even more salient because the exchange of code happens automatically