4 ms·
That's mostly true, but there's still the latency benefits of physical proximity. For example, just for an electric signal to travel 6000km across the country,
by orijing 15y ago
That's mostly true, but there's still the latency benefits of physical proximity. For example, just for an electric signal to travel 6000km across the country, it will take t=6000km/v where v=c/n (c = speed of light, 3e8 m/s and n = refractive index of fiber, 1.62). So it'll take 32.4 ms just to send a packet across the states, and another 32.4 ms to receive one back. This doesn't even take into effect the latency from the routers in the way, and other things like that your message doesn't go in a completely straight path.
So latency is really important if you're doing something like playing a real time game. 32ms is basically a single frame if you're playing at 30 fps. Some people will notice if they're constantly a frame behind.
[1] http://en.wikipedia.org/wiki/Optical_fiber http://en.wikipedia.org/wiki/Optical_fiber
- Klinky 15y agoLatency exists with any medium. Latency isn't really comparable to bandwidth, though a lack of bandwidth can impair latency. Most people aren't connecting to a server that is 3000 miles away from them, they are connecting to a CDN that is strategically located within a few states from them. Even in latency sensitive applications like gaming or VoIP, usually 100ms or less is enough for satisfactory results. Then there are a whole host of things where latency really doesn't matter all that much like file backup or video streaming...
- nl 15y agoI'm well aware of latency. I chose the example I did specfically because high bandwidth trumps locality when emailing a picture across the room..
- orijing 15y agoI wasn't saying that high speed internet is not good, just wanted to be careful in declaring that it'll make everything feel as fast as LAN. Not to mention the fact that the other endpoint needs to be as fast if you want fast communication.