[cassandravoiton]

You, sorry to say, utterly incorrect. The Paxos algorithm offers a clever way to making the choise of a single transactional arbitrator dynamic. For each transaction, it might be different, but for a single transcation, Paxos is only stable if the transactional co-ordinator is stable. if the network fails then an unknow state can be achieved and the entire system will have to restabalize to the values held in the single co-ordinator for the broken transaction.

[cx01]

Did you even read the Paxos Commit paper? There is no single arbitrator. And what is 'unknown state' intended to mean? The system will obviously always be in a known state. It will just block as long as there is no network connectivity.

[cassandravoiton]

Yes, I did read it... "

In practice, it is not di±cult to construct an algorithm that, except dur- ing rare periods of network instability, selects a suitable unique leader among a majority of nonfaulty acceptors. Transient failure of the leader-selection algorithm is harmless, violating neither safety nor eventual progress. One algorithm for leader selection is presented by Aguilera et al. [1] "

" The algorithm satisfies Stability because once an RM receives a decision from a leader, it never changes its view of what value has been chosen "

Fundamentally, the idea is that the leader is the transactional arbitrator using the RM as the recorder of that transaction.