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Posted Jul 27, 2009 12:31 UTC (Mon) by khim (subscriber, #9252)
Parent article: Google releases Neatx NX server

A proxying solution like NX can perhaps help to tackle the problem with less effort than optimizing the X client side, serving as a stopgap until everybody's latency is so low that no one cares anymore.

Latency will never go away. That's just fact of life. Speed of light is 300'000km/sec and Earth 40'000km thus minimum possible worst-case latency is 130ms. In reality it can be somewhat reduced by using few datacenters (like Google does), but it can not be reduced to make remote usage of X server "in the cloud" possible...

Posted Jul 27, 2009 23:16 UTC (Mon) by marcH (subscriber, #57642) [Link]

> Speed of light is 300'000km/sec...

... in vacuum. In fiber or electrical cables, it is typical 200,000. That's 5 milliseconds per 1000km. Multiply by two to get the round trip time, and multiply once again by (typically) two to account for buffering in processing in active network nodes.

Posted Jul 31, 2009 23:24 UTC (Fri) by sbergman27 (guest, #10767) [Link]

Why run a 40,000km cable when you could just run a 3 foot cable the opposite direction?

Posted Aug 1, 2009 9:59 UTC (Sat) by modernjazz (guest, #4185) [Link]

Well, those of us who live on Neptune don't think that solution will work
for us.

Posted Aug 2, 2009 4:40 UTC (Sun) by khim (subscriber, #9252) [Link]

Why run a 40,000km cable when you could just run a 3 foot cable the opposite direction?

If you'll use 3 feet cable you'll be 20'000km from destination. You get 40'000km when two points are antipodes: it does not matter which way you'll go it's 20'000km one way and then 20'000km another way - direction is irrelevant. The only way to reduce distance is to burrow a hole and the depeest hole known to a man (less then 15km) does not shrink the distance all that much...

Posted Aug 6, 2009 16:32 UTC (Thu) by phanser (guest, #60087) [Link]

40000 km is earth circumference,
see http://en.wikipedia.org/wiki/Earth

Exactly!

Posted Aug 9, 2009 12:12 UTC (Sun) by khim (subscriber, #9252) [Link]

The device capable of burrowing straigh through Earth? I know few guys who'll pay BIG BUCKS for such thing - where are selleing it?

And if you are not selling then the only way to go to the antipode is along the Earth surface - so yes, 40'000km (give or take) is shortest path available...

Exactly!

Posted Aug 13, 2009 19:46 UTC (Thu) by hummassa (subscriber, #307) [Link]

Come, on, you are being thick. 40000km is the CIRCUMFERENCE of the earth, ie, the distance you walk if you wanna make a FULL circunavigation.

The distance between antipodes is half that - 20000km ALONG THE EARTH SURFACE. It would be ~12000km thru the center of the Earth.

Exactly!

Posted Aug 13, 2009 19:58 UTC (Thu) by johill (subscriber, #25196) [Link]

And if your two machines are at antipodes, then your latency is the round trip, which will be ~40Mm.