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dstick

I saw these Starlink speed test results 2 weeks ago: https://tweakers.net/i/xDBb34kfMAju3YPPMsC3iOc2gXc=/656x/fil...

Seems like pretty solid latency :)

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30-100ms is better than I feared, and should be generally reasonable for most uses.

30 is really good actually. At least for what I’m used to.

On my home fiber, pretty much all sites I visit are like 80 ms away, Starlink would be an upgrade for me, latency-wise

anything above 100 ms is starting to get into unusable territory for quite a few applications

Count yourself lucky you don't live in either South America, Africa or Asia, where +100ms latency is more common than not. Fortunately I can count on one hand the applications that don't work with +100ms latency (not counting gaming). Usually it's the fault of the application developers (or rather the infrastructure team) where they put too low timeouts for requests rather than letting the requests go for a bit longer.

Sub 100ms for satellite internet is incredible, hopefully it'll be cheap enough for people to actually get, compared to the current satellite internet we have.

Can't wait for humanity to become a multi-planet species, as then application developers would have to start taking multi-minute latencies into account, and hopefully that'll help me as someone with ~500ms latency to most services.

> Fortunately I can count on one hand the applications that don't work with +100ms latency (not counting gaming).

Pardon my ignorance, but what are some exampes of applications that wouldn’t work with +100 latency?

Depends on where on the +100ms range we're on. Once you start hitting 1s latency, lots of applications (or rather, their servers) have a hard limit on 1s for every request. So when loading data from the backend, you have to continue to retry the request until it gets below 1s and then you will finally get the data.

I think Adobe been one of the worst companies I've dealt with personally, as many of the endpoints have ridiculously low timeouts (for someone with really shitty latency).

Voice chat is obnoxious with more than a few tens of ms latency.

Around about 100ms things stop appearing instantaneous, beyond the scope that everything starts to suck if you're not a patient person.

Gaming and video conferencing come to mind. Videoconferences need bandwidth for obvious reasons but it's also nice if you don't have any delays in when you says something and when the other side hears it. I've been in some calls lately with very noticable delays. Especially people joining from mobile phones tend to be affected (shit latency, variable bandwidth).

Anything that requires real-time interaction between a client and a server and other clients, e.g., gaming, stadia/geforce now, videoconferencing, ...

< 100ms is usually the "minimum", > 150ms is often "unusable", and for a smooth experience you might need < 30ms depending on the application (e.g. depending on the game you might need < 90ms or <60ms or <30ms).

Videoconferencing does not need imperceptible latency.

The other two things on your list are both gaming.

Depends how much you care about people talking over one another. If your call is a presentation/lecture/class with few switches between speakers, latency's no problem.

But if your calls normally have lively discussion where someone different jumps in any time there's a pause, the higher the latency the more likely people will say "meeting in person is much better"

Likewise, with things like remote desktop, 100ms of latency isn't a dealbreaker but it'll certainly leave some of your users saying "things that run locally just feel snappier"

For mobile phone networks, >20ms latency in audio is "unacceptable" from the point-of-view of standards conformance and a client "accepting" the hardware of some vendor.

Up to 100ms is kind of ok-ish barely-sluggish, but over 100ms latency, it becomes extremely annoying to maintain a conversation.

Video conferencing often makes this worse, because it is what people use for meetings, etc. and that involves more than 2 people maintaining a conversation, so latency becomes even more important there.

Otherwise 3-4 people start talking over each other, and none of them notices until they receive what the others are saying. Which is extremely annoying.

> Can't wait for humanity to become a multi-planet species, as then application developers would have to start taking multi-minute latencies into account, and hopefully that'll help me as someone with ~500ms latency to most services.

Stuff that requires realtime (or near realtime) communication simply won't be possible.

What remains is bulk data transfer, here I guess the only viable way is:

1) on both ends in both directions, massive buffers (at least bandwidth x 4)

2) massive FEC (of course it will reduce the net bandwidth, but there's no real other way to avoid lots of retransmissions)

3) sender station transmits the data in blocks, with each object of data having a specified number of blocks

3) receiver station checks all the data blocks for integrity, places it in buffers, and transmits back a list of broken blocks and a list of successfully received blocks

4) sender station receives the list of broken/successful blocks, deletes successful blocks from its buffer and retransmits those marked as broken

5) receiver station waits until all the blocks for an object of data have been successfully transmitted, and delivers the message to the recipient system

Yeah, in short: content-addressable systems are needed if we're ever to send data between planets on a larger scale. Systems like IPFS and alike solves this problem nicely, at least in my tests with high-latency scenarios.

We already have a protocol spec for stuff like this

https://tools.ietf.org/html/rfc5050

https://tools.ietf.org/html/draft-ietf-dtn-bpbis-26

Consistent 30ms would be pretty excellent, and make it useful for many things. Consistent 50ms, similarly. It starts to get a bit more of an issue at 80ms or 100ms, but my worry is more that jitter may be huge, and 30-100ms is a huge jitter window that could limit usefuless not just for games, but also many other things such as voice calls.

A 100ms ping is perfectly playable in everything except twitch-based shooters. In voice calls you will notice it, but it won't get in the way like say a 1-2s delay would (like you get if you phone from one end of the world to the other). It's really a very good result bearing in mind that this can work absolutely anywhere.

Fighting games, too. Most gamers know to avoid wifi, much less a wireless ISP.

I don't think that's still true with 802.11ac. My Wi-Fi adds only 1 or 2 ms latency. There is way more jitter, but it doesn't really matter if the total is always under 10ms.

wifi doesn't add any latency, inhernetly. nor in practice with actual equipment

The shared medium (frequency spectrum) is what can add latency. If a device wants to talk over Wifi but another device is transmitting it has to wait. This introduces (variable) latency, aka jitter.

Here's an anecdotal example for you, in practice with actual equipment:

1) Mac pro via ethernet to router:

    # ping -c 5 -S 192.168.1.88 192.168.1.1
    PING 192.168.1.1 (192.168.1.1) from 192.168.1.88: 56 data bytes
    64 bytes from 192.168.1.1: icmp_seq=0 ttl=64 time=0.413 ms
    64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=0.396 ms
    64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=0.417 ms
    64 bytes from 192.168.1.1: icmp_seq=3 ttl=64 time=0.553 ms
    64 bytes from 192.168.1.1: icmp_seq=4 ttl=64 time=0.514 ms

    5 packets transmitted, 5 packets received, 0.0% packet loss
    round-trip min/avg/max/stddev = 0.396/0.459/0.553/0.063 ms

2) Same machine via wifi over Unify AP to router:

    # ping -c 5 -S 192.168.1.72 192.168.1.1
    PING 192.168.1.1 (192.168.1.1) from 192.168.1.72: 56 data bytes
    64 bytes from 192.168.1.1: icmp_seq=0 ttl=64 time=2.992 ms
    64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=4.136 ms
    64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=1.873 ms
    64 bytes from 192.168.1.1: icmp_seq=3 ttl=64 time=2.293 ms
    64 bytes from 192.168.1.1: icmp_seq=4 ttl=64 time=2.552 ms

    5 packets transmitted, 5 packets received, 0.0% packet loss
    round-trip min/avg/max/stddev = 1.873/2.769/4.136/0.774 ms

That's an average of 2.3ms extra latency, or 6x higher.

I speak a lot with customers on satellite phones more or less every day. When they are calling from a BGAN terminal the latency can be a problem. Latency is around 1000-1500ms. But when speaking on a VSAT Ka-band terminal the latency is less of a problem. Data latency is around 600-800ms on VSAT. So I doubt latency of 100ms would be a problem at all. Most VOIP solutions have some mechanisms to reduce the perceived latency.

I'm struggling to imagine a network path that could induce a 1-2 second delay from one side of the world to the other. Even at just 50% of c-in-vacuum that's only a tenth of a second.

There's a lot of active gear introducing delays between those ends. Pinging www.govt.nz, which is about 17000km from me and as close to the antipode as I can find in a quick search, pings at around 300 to 400ms, so only at about 15 to 20% of c.

Huh. My nearest land antipode (from Boston, MA, USA) is Perth, and I get about 150ms ping to there. Regardless, even 400 ms is a far cry from 2000 ms.

A ping is a round trip, so you have to double the distance.

Even in an FPS unless you are trying to play at a pro level or something 100ms will be barely noticeable. Your reaction time is already probably over 300ms

One thing that may be a game changer: inter-satellite relaying. With the whole network, Starlink client to Starlink client latency might actually drop.

What sort of areas is low latency important in outside of video games?

Finance, stock trading. Theoretically Starlink should eventually have lower latency than the optical cables under the Atlantic.

I wonder when the first CDN's will be put into space when this will become broadly used.

This got me thinking... people _will_ start putting infra into space sooner or later, just for the better latency. Imagine the new availability zones in aws/gcp/azure :)

Could definitely lead to more investment into space, more money to SpaceX / Blue Origin / etc for their new-gen lift vehicles.

Would that not be impossible because of the lack of effective cooling in space? The only way to get rid of heat in space is by radiation, which is a very inefficient process. Assuming temperatures cannot rise above 100°C, every square meter of radiator fin emits at most a kilowatt. And because half the orbit is spent in direct sunlight, a significant part of the surface area will have to be reflective, making it useless for radiating heat.

Also, where'd you get the power? Solar panels will only yield a kilowatt per square meter at most, for half of the orbit. Beam it up from Earth?

That's actually better than what most 3rd world countries got, oh god.

It’s better than what most of the US has (by land not people)

I would guess the same for the UK - certainly for Scotland :-(

Edit: Surprisingly little of the UK is actually built up areas: https://www.sheffield.ac.uk/news/nr/land-cover-atlas-uk-1.74...

That really is surprising considering it’s just an island (or a few islands? I can never remember wether Ireland/isle of man is included.) It’s weird how expensive housing can get when there’s so much empty space.

Part of the island of Ireland, Northern Ireland, is part of the UK the rest being the Republic of Ireland (which everyone not in NI refers to as just Ireland).

The Isle of Man isn't part of the UK, though it is a Crown Dependency.

This is all just as confusing as it sounds...

is that real? how are they beating the speed of light?

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