text: This paper investigates under which conditions information can be reliably shared and consensus can be solved in unknown and anonymous message-passing networks that suffer from crash-failures. We provide algorithms to emulate registers and solve consensus under different synchrony assumptions. For this, we introduce a novel pseudo leader-election approach which allows a leader-based consensus implementation without breaking symmetry.
  @cite_5: We present here two consensus algorithms in shared memory asynchronous systems with the eventual leader election failure detector *** . In both algorithms eventually only the leader given by failure detector *** will progress, and being eventually alone to make steps the leader will decide. The first algorithm uses an infinite number of multi-writer multi-reader atomic registers and works with an unbounded number of anonymous processes. The second uses only a finite number of single-writer multi-reader registers but assumes a finite number of processes with known unique identities.
  @cite_3: 
  @cite_7: We determine what information about failures is necessary and sufficient to solve Consensus in asynchronous distributed systems subject to crash failures. In Chandra and Toueg [1996], it is shown that W , a failure detector that provides surprisingly little information about which processes have crashed, is sufficient to solve Consensus in asynchronous systems with a majority of correct processes. In this paper, we prove that to solve Consensus, any failure detector has to provide at least as much information as W. Thus, W is indeed the weakest failure detector for solving Consensus in asynchronous systems with a majority of correct processes.
summary: There have been several approaches to solve fault-tolerant consensus in anonymous networks deterministically. In @cite_5 , fault-tolerant consensus is solved under the assumption that failure detector @math @cite_7 exists, i.e. exactly one correct process eventually knows forever that it is the leader. In @cite_3 , fault-tolerant and obstruction-free For obstruction-free consensus, termination is only guaranteed if a process can take enough steps without beeing interrupted by other processes. consensus is solved if registers are available.