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Though the transactional latency is important especially for achieving consensus, most of the latency is computational that is much greater than the communications latency. Possibly PingER RTT could be included in a measure of BlockChain health and status. Bebo sent a reference (https://mastanbtc.github.io/blockchainnotes/consensustypes/) pointing out milliseconds may make a difference to miners to get rewards whichis is important for BlockChain cash
Saqib sent email of an analysis of the impact of various RTTs, see https://ethereum.stackexchange.com/questions/18201/does-network-latency-significantly-affect-mining-rewards.
PingER at SLAC (Updated 6/7/2018)
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