However, if you had a bit of a kink in the hose then you might find the water comes out in spurts. This is similar to if you have an unstable Internet connection then the data could come through in spurts - that would impact the latency of a specific droplet of water (or packet of data).

Like your hose analogy - the last bit though sounds a lot like 'jitter'

The speed of light is still the constant - ADSL is still at the speed of light. The issue is that the bandwidth available for optical signals is much much wides than a copper pair. Far greater than is used. Metal pairs are limited by their ability to retain and carry higher frequencies. These are lost over distances and you need the bandwidth to carry the faster signalling speeds. Lose the higher carrier frequencies and you lose the bandwidth. In optical systems these losses don’t happen in the same way because the light is bouncing along a pipe that reflects the photons back from the edges with almost zero loss. Metal cannot do that. To retain the frequencies for longer in metal we switch to coax rather than twisted pairs. Physics is king here.

Sadly there’s no such thing (unless you go into wierd science and cryo-tech) that gives lossless copper/metal transmission lines.

Switching speeds through the network hardware will also impact latency. Every joint will have an impact, large or small.

In reply to a post by AndrewNi:

FTTP is almost always going to have a lower latency than ADSL because it uses light (rather than electricity) for a larger portion of the distance between you and the destination.

From what I've read, that isn't true. The speed of light in fibre is about 70% of the speed in a vacuum, which is about the same as the propagation speed of a typical electric signal.

In reply to a post by andynormancx:

In reply to a post by AndrewNi:

FTTP is almost always going to have a lower latency than ADSL because it uses light (rather than electricity) for a larger portion of the distance between you and the destination.

From what I've read, that isn't true. The speed of light in fibre is about 70% of the speed in a vacuum, which is about the same as the propagation speed of a typical electric signal.

Its the switching delays, including backhaul and trunk nets, layer 3 routing variability, that contribute mostly to latency "on-shore" though.

Undersea links because of the enormous distances, the speed of light in fibre, it becomes far more of a prevalent factor. Hence the moves towards state of the art hollow-core fibre and highly optimised undersea paths especially for traffic for electronic trading platforms where cost is not an issue but every ns of time saved very much is.

Starlink have promised direct laser links between their LEO birds that have the potential to be faster than terrestrial fibre routes. GEO sats fixed in position above the equator, are too high up to benefit from this technique - but LEO's orbiting at roughly 500 km above sea level are a contender.

Hi, first of all thanks for all the great replies!

I think I have a better understanding of it.

Two things however:

1. I have been told that this ADSL connection has interleaving enabled. I think that adds latency. Would it be worth considering disabling interleaving?
2. Someone told me about buffer bloat, and how that could increase one's latency. As a possible solution that someone suggested getting another router that can handle buffer bloat. Would this be worth considering in your opinion?

Interleaving does add latency but it increases stability. If you ask them to force it to turn off then you may end up with an unstable line.

If you want to learn about buffer bloat go and have a look here:

https://www.bufferbloat.net/projects/bloat/wiki/What...

But, unless you do lots of online gaming or you have problems with VOIP or video calls, just don't worry about it.

In reply to a post by andynormancx:

If you want to learn about buffer bloat go and have a look here:

https://www.bufferbloat.net/projects/bloat/wiki/What...

But, unless you do lots of online gaming or you have problems with VOIP or video calls, just don't worry about it.

Well I do lots of online gaming! So should I just follow the advice from that site?

And do you actually have any issues with unusually high latency ?

I like the analogy. Would you mind if I passed it on to colleagues at work ?