[TML] A little tinkering with Lasers

[Timothy Little]

shadow at shadowgard.com wrote:
> Actually it's *not* essentially zero. Otherwise you wouldn't notice
> the lag time on a satellite link compared with a cable across the
> seafloor.

The usual consumer satellite links travel drastically further than
necessary, and the situation is made worse by the usual behaviour of
TCP to latency (interpreting it as congestion and slowing down).  Then
there's actual congestion on top of that.

The actual geosync light speed latency is less than 600 ms, and that's
for a relay in a *very* high orbit: about 6 times Earth's radius.  The
minimum round-trip time for a ping from Tasmania to a site in the UK
(via cables) is about 350 ms.  The difference would be noticeable, but
not huge.

One factor not previously mentioned: fibre optic cables have a fairly
high index of refraction, which means that light travels slower
through them than through space - typical about 2/3 of the speed.  A
satellite-routed connection could theoretically have *lower* latency
than very long distance cable links, if the relays were closer to
Earth.


In short, yes it is true that meson communicators would permit lower
latency communication between sites separated by planetary mass.  In
practice I don't think it would make a lot of difference.


- Tim