In a hybrid peer-to-peer environment, clients can either directly download data from their server, or share data with each other. In order to create incentives for clients to share data and decrease server load, an effective economy model is for the server to credit those provider clients who provide data to others and offer discounts to those recipient clients who download data from provider clients instead of the server. To realize this model, the proof of service between provider and recipient clients must be provided.

We design and investigate three different schemes and compare them in terms of scalability, effectiveness, and cost. We emphasize the issues of lessening the number of proofs which must be provided, avoiding a heavy load on the server, and ensuring the proof for every piece of data served. Our study shows our enhanced public-key-based scheme to be the most effective.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Jun Li
    • 1
  • Xun Kang
    • 1
  1. 1.Department of Computer and Information ScienceUniversity of Oregon 

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