LWN.net Logo  TCP Fast Open: expediting web services  TCP Fast
Open: expediting web services  Posted Aug 2, 2012 15:57 UTC
(Thu) by gdt (guest, #6284) Parent article: TCP Fast Open:
expediting web services  "Router latencies" isn't really an
issue, as they are easily enough solved by increasing the
bandwidth (which reduces the time to receive and transmit a
packet). (And yeah, I'm avoiding the "bufferbloat"
overprovisioning of buffers at the network edge here, because
when that exists RTO is not much help -- saving one RTT when you
have multiple RTT in the queue ahead of you isn't a huge win.)
The speed of light in optical fiber is the major contributor to
latency. The speed of light in fiber is roughly 150Km per ms,
this is much slower than the speed of light in a vacuum. The
speed of light in a fiber can be improved, but at the cost of
narrowing bandwidth. This tradeoff isn't available to users, but
is determined during ITU standards-making. Moreover the tradeoff
isn't huge, in the order of 5% of latency.