Keeping track of the latest gossip: Bounded time-stamps suffice
Consider a distributed system consisting of N independent communicating agents. Periodically, agents synchronize and exchange information, both about each other and about agents they have talked to earlier. As a result, an agent a t may receive indirect information about another agent a j which is more recent than the information exchanged in the last direct synchronization between a i and a j . The problem is to ensure that agents always come away from a synchronization with the latest possible information about all other agents. This requires that when a i and a j meet, they should decide which of them has more recent information about any other agent a k . We propose an algorithm to solve this problem which is finite-state and local. Formally, this means our algorithm can be implemented by an asynchronous automaton.
KeywordsDistributed algorithms synchronous communication bounded time-stamping asynchronous automata
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