Theoretical minimum round-trip-time for a packet to travel over/under the North Atlantic Sea?
I'm doing some performance tuning and capacity planning for a low-latency application and have the following question:
What is the theoretical minimum round-trip time for a packet sent开发者_运维技巧 between a host in London and one in New York connected via optical fiber?
I believe the index of refraction of fiber is around 1.5, and the internet reports it's around 5600 km from NY to London, so the theoretical minimum one-way is 5600 km / (c/1.5) =~ 28 ms
. Round-trip is double that, 56 ms.
Up to you to do the real work of estimating latency through your routers and all.
P.S. The cables might not be straight :p
Edit: A bit of the wikipedia article on optical fiber pretty much contains all this information.
Just ask Hibernia, they currently are at 72ms and presently looking at 60ms by mid-2012.
http://www.a-teamgroup.com/article/andrews-blog-laying-cable-and-the-low-latency-gauntlet/
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