Determine asymmetric latencies in a network

Question

Imagine you have many clustered servers, across many hosts, in a heterogeneous network environment, such that the connections between servers may have wildly varying latenci

Answer 1

In absence of a synchronized clock, the asymmetry cannot be measured as proven in the 2011 paper "Fundamental limits on synchronizing clocks over networks".

https://www.researchgate.net/publication/224183858_Fundamental_Limits_on_Synchronizing_Clocks_Over_Networks