Xavier Araújo Morgado Vilaça

N-Party BAR Transfer

Tese submetida para provas de mestrado em Engenharia Informática e de Computadores Instituto Superior Técnico, Universidade Técnica de Lisboa.


Peer-to-peer networks have emerged as a relevant architecture for executing scientific computations. However, this kind of networks poses several problems. This thesis addresses the problem of data storage in a peer-to-peer architecture. We consider several distinct behaviors of the participating nodes. To deal with this variety, we use the BAR model, that comprises Byzantine, Rational, and Altruist peers. In this report, we provide a survey on peer-to-peer storage solutions and on different approaches to deal with byzantine and rational peers. We also propose a new protocol (NBART) for reliably transferring data from a set of N producers to a set of N consumers, when up to f producers and/or f consumers are Byzantine, and when the remaining participants are either Rational or Altruist. This protocol serves as a building block for our storage subsystem, by preserving the data through successive transfers. We perform an analytical evaluation that aims at proving the correctness of the protocol and showing that it is on each Rational participant interest to follow the expected behavior.


N-Party BAR Transfer
Xavier Araújo Morgado Vilaça
MSc Thesis. Instituto Superior Técnico, Universidade Técnica de Lisboa.
October, 2011.
Available BibTeX, MSC Thesis, extended abstract of the thesis, and mid-term report.
N-party BAR Transfer.
X. Vilaça, J. Leitão, M. Correia and L. Rodrigues.
In Proceedings of the the 15th International Conference On Principles Of DIstributed Systems (OPODIS), Toulouse, France, December, 2011.
Available BibTeX, abstract (html) and report (pdf).
N-party BAR transfer: Motivation, Definition and Challenges.
X. Vilaça, J. Leitão, L. Rodrigues.
In proceedings of the 3rd Workshop on Theoretical Aspects of Dynamic Distributed Systems (in conjunction with DISC 2011), Rome, Italy, September 19, 2011.
Available BibTeX, abstract (html) and report (pdf).
Transferência de Dados entre Grupos de Processos no Modelo BAR.
X. Vilaça, J. Leitão, and L. Rodrigues.
Actas do terceiro Simpósio de Informática (Inforum), Coimbra, Portugal, Sep, 2011
Prémio melhor artigo de estudante INForum 2011.
Available BibTeX, extended report (pdf).

Luís Rodrigues