A New TransAtlantic Cable System

Sat Oct 2 18:28:02 UTC 2010

http://www.gcmap.com/mapui?P=lga-lhr

--
kris

On Oct 2, 2010, at 7:31 AM, Jon Meek wrote:

> One of the ways that I have tormented WAN vendors over the years is
> with a plot of RTT vs. great circle distance between the end points of
> a circuit. Most RTTs usually sit at some constant offset above that
> Physics limit straight line. Circuits taking a less than ideal have
> their RTT far above the Physics limit line and we have used that
> information to get routes fixed.
> 
> Using my great circle program that accounts for the non-spherical
> Earth for locations we have West of London and North of NYC, assuming
> a 1.5 index of refraction I get:
> 
> One way distance: 5520.6 km   Round Trip Delay: 55.2 ms
> 
> So Heath's estimate is right on, although depending on where he got
> the distance maybe it does account for the shape of the Earth.
> 
> Jon
> 
> On Sat, Oct 2, 2010 at 6:17 AM, Heath Jones <hj1980 at gmail.com> wrote:
>> On 2 October 2010 10:52, Rod Beck <Rod.Beck at hiberniaatlantic.com> wrote:
>>> Is that a straight line calculation or did you take into account that a
>>> straight line is not the shortest path on a curved surface?
>> 
>> Well that is pretty obvious to most, but no - I didn't go to the
>> effort of factoring in curvature of the earth - especially given that
>> 1.5 is very rough figure anyway for RI of glass. If anything, my
>> comment was compliment to your network being close to minimum possible
>> latency!
>> 
>> 
> 