The irtt command, run with normal, light usage: https://drive.google.com/file/d/1SiVCiUYnx7nDTxIVOY5w-z20S2O059rA/view?usp=share_link Jonathan Bennett Hackaday.com On Fri, Jan 13, 2023 at 11:26 AM Dave Taht wrote: > packet caps would be nice... all this is very exciting news. > > I'd so love for one or more of y'all reporting such great uplink > results nowadays to duplicate and re-plot the original irtt tests we > did: > > irtt client -i3ms -d300s myclosestservertoyou.starlink.taht.net -o > whatever.json > > They MUST have changed their scheduling to get such amazing uplink > results, in addition to better queue management. > > (for the record, my servers are de, london, fremont, sydney, dallas, > newark, atlanta, singapore, mumbai) > > There's an R and gnuplot script for plotting that output around here > somewhere (I have largely personally put down the starlink project, > loaning out mine) - that went by on this list... I should have written > a blog entry so I can find that stuff again. > > On Fri, Jan 13, 2023 at 9:02 AM Jonathan Bennett via Starlink > wrote: > > > > > > On Fri, Jan 13, 2023 at 6:28 AM Ulrich Speidel via Starlink < > starlink@lists.bufferbloat.net> wrote: > >> > >> On 13/01/2023 6:13 pm, Ulrich Speidel wrote: > >> > > >> > From Auckland, New Zealand, using a roaming subscription, it puts me > >> > in touch with a server 2000 km away. OK then: > >> > > >> > > >> > IP address: nix six. > >> > > >> > My thoughts shall follow later. > >> > >> OK, so here we go. > >> > >> I'm always a bit skeptical when it comes to speed tests - they're really > >> laden with so many caveats that it's not funny. I took our new work > >> Starlink kit home in December to give it a try and the other day finally > >> got around to set it up. It's on a roaming subscription because our > >> badly built-up campus really isn't ideal in terms of a clear view of the > >> sky. Oh - and did I mention that I used the Starlink Ethernet adapter, > >> not the WiFi? > >> > >> Caveat 1: Location, location. I live in a place where the best Starlink > >> promises is about 1/3 in terms of data rate you can actually get from > >> fibre to the home at under half of Starlink's price. Read: There are few > >> Starlink users around. I might be the only one in my suburb. > >> > >> Caveat 2: Auckland has three Starlink gateways close by: Clevedon (which > >> is at a stretch daytrip cycling distance from here), Te Hana and Puwera, > >> the most distant of the three and about 130 km away from me as the crow > >> flies. Read: My dishy can use any satellite that any of these three can > >> see, and then depending on where I put it and how much of the southern > >> sky it can see, maybe also the one in Hinds, 840 km away, although that > >> is obviously stretching it a bit. Either way, that's plenty of options > >> for my bits to travel without needing a lot of handovers. Why? Easy: If > >> your nearest teleport is close by, then the set of satellites that the > >> teleport can see and the set that you can see is almost the same, so you > >> can essentially stick with the same satellite while it's in view for you > >> because it'll also be in view for the teleport. Pretty much any bird > >> above you will do. > >> > >> And because I don't get a lot of competition from other users in my area > >> vying for one of the few available satellites that can see both us and > >> the teleport, this is about as good as it gets at 37S latitude. If I'd > >> want it any better, I'd have to move a lot further south. > >> > >> It'd be interesting to hear from Jonathan what the availability of home > >> broadband is like in the Dallas area. I note that it's at a lower > >> latitude (33N) than Auckland, but the difference isn't huge. I notice > >> two teleports each about 160 km away, which is also not too bad. I also > >> note Starlink availability in the area is restricted at the moment - > >> oversubscribed? But if Jonathan gets good data rates, then that means > >> that competition for bird capacity can't be too bad - for whatever > reason. > > > > I'm in Southwest Oklahoma, but Dallas is the nearby Starlink gateway. In > cities, like Dallas, and Lawton where I live, there are good broadband > options. But there are also many people that live outside cities, and the > options are much worse. The low density userbase in rural Oklahoma and > Texas is probably ideal conditions for Starlink. > >> > >> > >> Caveat 3: Backhaul. There isn't just one queue between me and whatever I > >> talk to in terms of my communications. Traceroute shows about 10 hops > >> between me and the University of Auckland via Starlink. That's 10 > >> queues, not one. Many of them will have cross traffic. So it's a bit > >> hard to tell where our packets really get to wait or where they get > >> dropped. The insidious bit here is that a lot of them will be between 1 > >> Gb/s and 10 Gb/s links, and with a bit of cross traffic, they can all > >> turn into bottlenecks. This isn't like a narrowband GEO link of a few > >> Mb/s where it's obvious where the dominant long latency bottleneck in > >> your TCP connection's path is. Read: It's pretty hard to tell whether a > >> drop in "speed" is due to a performance issue in the Starlink system or > >> somewhere between Starlink's systems and the target system. > >> > >> I see RTTs here between 20 ms and 250 ms, where the physical latency > >> should be under 15 ms. So there's clearly a bit of buffer here along the > >> chain that occasionally fills up. > >> > >> Caveat 4: Handovers. Handover between birds and teleports is inevitably > >> associated with a change in RTT and in most cases also available > >> bandwidth. Plus your packets now arrive at a new queue on a new > >> satellite while your TCP is still trying to respond to whatever it > >> thought the queue on the previous bird was doing. Read: Whatever your > >> cwnd is immediately after a handover, it's probably not what it should > be. > >> > >> I ran a somewhat hamstrung (sky view restricted) set of four Ookla > >> speedtest.net tests each to five local servers. Average upload rate was > >> 13 Mb/s, average down 75.5 Mb/s. Upload to the server of the ISP that > >> Starlink seems to be buying its local connectivity from (Vocus Group) > >> varied between 3.04 and 14.38 Mb/s, download between 23.33 and 52.22 > >> Mb/s, with RTTs between 37 and 56 ms not correlating well to rates > >> observed. In fact, they were the ISP with consistently the worst rates. > >> > >> Another ISP (MyRepublic) scored between 11.81 and 21.81 Mb/s up and > >> between 106.5 and 183.8 Mb/s down, again with RTTs badly correlating > >> with rates. Average RTT was the same as for Vocus. > >> > >> Note the variation though: More or less a factor of two between highest > >> and lowest rates for each ISP. Did MyRepublic just get lucky in my > >> tests? Or is there something systematic behind this? Way too few tests > >> to tell. > >> > >> What these tests do is establish a ballpark. > >> > >> I'm currently repeating tests with dish placed on a trestle closer to > >> the heavens. This seems to have translated into fewer outages / ping > >> losses (around 1/4 of what I had yesterday with dishy on the ground on > >> my deck). Still good enough for a lengthy video Skype call with my folks > >> in Germany, although they did comment about reduced video quality. But > >> maybe that was the lighting or the different background as I wasn't in > >> my usual spot with my laptop when I called them. > > > > Clear view of the sky is king for Starlink reliability. I've got my > dishy mounted on the back fence, looking up over an empty field, so it's > pretty much best-case scenario here. > >> > >> > >> -- > >> > >> **************************************************************** > >> Dr. Ulrich Speidel > >> > >> School of Computer Science > >> > >> Room 303S.594 (City Campus) > >> > >> The University of Auckland > >> u.speidel@auckland.ac.nz > >> http://www.cs.auckland.ac.nz/~ulrich/ > >> **************************************************************** > >> > >> > >> > >> _______________________________________________ > >> Starlink mailing list > >> Starlink@lists.bufferbloat.net > >> https://lists.bufferbloat.net/listinfo/starlink > > > > _______________________________________________ > > Starlink mailing list > > Starlink@lists.bufferbloat.net > > https://lists.bufferbloat.net/listinfo/starlink > > > > -- > This song goes out to all the folk that thought Stadia would work: > > https://www.linkedin.com/posts/dtaht_the-mushroom-song-activity-6981366665607352320-FXtz > Dave Täht CEO, TekLibre, LLC >