Distributed Algorithms Chapter 4' Distributed Consensus

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Distributed Algorithms Chapter 4. Distributed
Consensus
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the problem

• given a network
• each site is pending or agreed.
• to be guaranteed
• if all sites are agreed, they remain agreed
  forever
• the difficulty
• all sites are agreed is a distributed property.
• the idea
• messages request to agree

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the algorithm
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to be shown
if agreed sites U then initiated requests ?
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to be shown if B.U then D.?
5. r(A) r(B) M by 1. and 4. 6. r(B) D lt
M by 2. 5. 3. 7. claim follows from 4. and
6.

• A B U invariant
• C D M invariant
• r(A) C gt r(U) trap
• 4. r(U) M by construction

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End ofDistributed Algorithms Chapter 4.
Distributed Consensus
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4 th Advanced Course on Petri Nets End
of Distributed Algorithms
further readingW. Reisig Elements of
Distributed Algorithms Springer Verlag 1998