最早流传的数字是Google的Jeaf Dean的《构建大型分布式系统的设计,教训和建议》。 (Designs, Lessons and Advice from Building Large Distributed Systems by Jeaf Dean.)
http://www.cs.cornell.edu/projects/ladis2009/talks/dean-keynote-ladis2009.pdf
Latency Numbers Every Programmer Should Know · GitHub
硬件和计算机网络都在发展,前面的数据是2010年左右,下面这个会持续更新,最新是2020年左右的,出自伯克利大学:
Numbers Every Programmer Should Know By Year