[Starlink] Starlink for Tonga?
Ulrich Speidel
u.speidel at auckland.ac.nz
Tue Apr 19 21:06:26 EDT 2022
FWIW, a few weeks ago I had a fit of creative rage after someone asked
whether it would even make sense for Tonga to rebuild the cables. It's
resulted in an APNIC blog, which has just been published, and which
argues that we've been approaching cable projects in the Pacific from
the wrong end as dead-end streets to islands, rather than aiming for a
resilient cable mesh that results in redundancy for everyone, including
the bigger economies around the place:
https://blog.apnic.net/2022/04/20/rethinking-submarine-fibre-cable-projects-south-pacific/
<https://blog.apnic.net/2022/04/20/rethinking-submarine-fibre-cable-projects-south-pacific>
On 20/04/2022 12:43 am, Ulrich Speidel wrote:
>
> I can probably comment on this.
>
> The international cable went back into service on the 22nd of
> February, one day before the official commencement of service to Tonga
> by Starlink. Now I should probably add here that you can't order
> Starlink in Tonga - they sent 50-odd terminals care of the Tongan
> government, and that's it. Since these were no longer needed in
> Tongatapu, they were meant to go to various of the other islands. The
> "Reliance" wasn't able to recover much of the domestic cable and for
> lack of spares wasn't able to fix this one. It subsequently left the
> cable grounds, unable to dock in Tonga due to Covid restrictions. New
> cable is on order in France but probably about another 8 months away,
> minimum.
>
> The biggest other islands, Vava'u and Ha'apai (more precisely, Lifuka
> - pronounced Li-Foo-Kah) already had other satellite links in service,
> and quite a bit of the GEO capacity directed at Tongatapu was shifted
> to them post Tongatapu's reconnection. So I'd expect most of the
> terminals to end up on some of the smaller islands - quite who gets to
> use them there I'm not privy to.
>
> I understand that the government technician trying one of the Dishys
> in Tongatapu got 300 Mb/s down out of it, probably not surprising
> given that there wouldn't have been any competing traffic. Alas, I
> understand that service is a bit discontinuous, which is to be
> expected. I've tried to ask them as to how frequent and long the gaps
> are, but haven't had a response.
>
> Tonga is still in Covid border closure mode, which means that few
> people are able to travel back and forth. One person that has been
> able to travel there is Shane Cronin, our volcanologist whom I was
> talking to, and he has been out of quarantine and is doing some
> interesting work up there - he even made the front page of the BBC
> World Service the other week:
> https://www.bbc.com/news/science-environment-61071293
>
> First reports we've had from him suggest that there was still quite a
> bit of action after the international cable was knocked out. He's
> quite familiar with Hunga and was able to pinpoint which earlier
> eruptions various of the bits that were left had come from. He's been
> trying to get a record of vessels in the area at the time to get ash
> reports from BigOceanData and they promised to help. Alas, this
> coincided with a sudden surge in demand for superyacht tracking, which
> presumably has kept them busy, so we've not seen this data set yet.
> What we do know is that tsunami run-up on Tongatapu's West Coast was
> about 15 metres - far bigger than the waves whose videos still made it
> across the cable. Shane has also been able to look at some of the
> tsunami deposits and this is likely to yield some further insights.
>
> Meanwhile, Emily Lane from NIWA has done some modelling around the
> pyroclastic density currents (turbidity currents of volcanic origin)
> that could have come off Hunga. The amount of material displacement
> involved in these simulations is in the several cubic kilometres!
> These show those flows actually reaching both cable grounds, the
> domestic one first. The domestic cable was essentially at the bottom
> of a trench straight downhill from Hunga and never stood a chance -
> not only do the simulations show the flow going across the trench
> eastbound, but then reflecting off the opposite side back into the
> trench before flowing out of the trench like water in a gutter. No
> wonder they couldn't find anything! The international cable grounds
> would have been reached later, first on the western side where they
> found the murky water weeks later, and then also on the eastern side,
> where the cable was pushed north. That said, according to the
> simulations, the first flow reaching the eastern side would have
> gotten there well before the outage, and doesn't quite explain the 5
> km displacement. That said, the simulation was only run until
> international cable outage time, and there's some question as to the
> validity of these results generally as nobody knows whether the
> bathymetry in the area was still anywhere near what it used to be.
> NIWA and others are sending ships up to get clarity as to how the
> seafloor topography has changed in the area. Hunga used to have a huge
> caldera, and at this point, nobody knows whether it's still there, has
> subsided, or got blasted away. Lots of interesting science happening
> there at the moment.
>
> On 20/04/2022 12:06 am, Dave Taht wrote:
>
>> On Tue, Apr 19, 2022 at 4:57 AM Mike Puchol <mike at starlink.sx> wrote:
>> >
>> > Apologies for resurrecting an old thread, but I had totally missed
>> this post:
>> >
>> >
>> http://www.fintel.com.fj/pages.cfm/company/news/spacex-starlink-gateway--fintel.html
>> <http://www.fintel.com.fj/pages.cfm/company/news/spacex-starlink-gateway--fintel.html>
>> >
>> > It seems the gateway was setup in Fintel’s existing earth station,
>> four antennas only, however, and the cables in surface ducts.
>>
>> No apologies needed, in fact, does anyone know how well tonga is
>> recovering?
>>
>> > Best,
>> >
>> > Mike
>> > On Feb 25, 2022, 20:12 +0300, Ulrich Speidel
>> <u.speidel at auckland.ac.nz>, wrote:
>> >
>> > I've heard nothing further about teleport establishment in Fiji,
>> but that doesn't mean that nothing has happened.
>> >
>> > Meanwhile, cable repair has progressed a good bit. The damage was
>> far greater than originally envisaged. On the international cable,
>> faults (complete cable ruptures and fibre damage) stretched over more
>> than 80 km. The cable ran entirely SOUTH of the Hunga Tonga Hunga
>> Ha'apai volcano (about 60 km away and shielded by a number of
>> submarine mounts for at least parts of the damaged section). Yet the
>> Reliance cable ship traced one disconnected cable piece end to about
>> 5 km NORTH of its nominal route, found various sections had
>> disappeared completely, and recovered sections of up to 9 km at a
>> time from the seabed.
>> >
>> > A bog standard cable break requires two holding drives (or drags),
>> HD for short, to pick up each of the cable endpoints from the
>> seafloor. It also requires either an ROV dive to check if the cable
>> has completely separated at the fault position, or a cut if the cable
>> is still held together by the steel. That cut can be done either by
>> ROV as well, or if visibility doesn't permit ROV use, by a cutting
>> drive (CD). Any HD or CD requires the cable ship to tow a seafloor
>> grapnel / cutter device transversally across the cable, so they're
>> easy to spot on position traces. The Reliance did no fewer than seven
>> HD's in its eastern operations area near Tongatapu, where it worked
>> first. Visibility there was good (so ROV could be used), but damage
>> substantial.
>> >
>> > The ship then proceeded to the western end of the fault zone where
>> reflectometer measurements from the Suva end had found a fault.
>> Because of bad visibility, they did a CD followed by 2 HD's there,
>> then noticed that there was fibre damage along the cable to Suva, so
>> reeled that in and cut the damaged bit out.
>> >
>> > They then proceeded to put a "mini-system" together. Let me
>> explain: Enroute to Tonga, the Reliance stopped at Subcom's depot in
>> Apia (Samoa) to load whatever cable they had in store there. This
>> included spares not only for the Fiji-Tonga cable but also for
>> various other cable systems in the wider region. Reliance left Apia
>> with about 80 km of cable in total. The amount of cable that will
>> need to be re-laid along the damaged international section is 90 km
>> (you need to allow for a bit of cable lengthening due to slack being
>> inserted when cable ends are being brought up from 2000 m (6000 ft)
>> or so below). This means that the Reliance is re-using some of the
>> cable recovered from the damaged section, and the whole "mini-system"
>> will be one long stitch job. The damaged section also included a
>> repeater worth US$230k, which they were trying to recover and which
>> was still missing as of this morning - I've yet to hear from my
>> contact as to whether they were successful on the last recovery
>> attempt today (they've left the area after three drives and are
>> heading West right now. The rest of the mini-system was going to be
>> laid after the repeater recovery attempt (the overall success doesn't
>> depend on the repeater being found, but the final repair bill does).
>> I thus expect the cable repair to be completed in the next few days.
>> >
>> > The domestic cable is another story altogether, unfortunately. This
>> has a blind stretch of 77 km at present, as measured by optical
>> reflectometer from Tongatapu and Ha'apai (there was meant to be a
>> measurement from Vava'u yesterday but I haven't heard yet what this
>> revealed, the cable from Tongatapu has two fibre pairs, one of which
>> heads to each destination from a branching unit west of Ha'apai. That
>> said, once the international cable has been fixed, the Reliance won't
>> have enough cable left to complete the domestic job, even if some
>> cable bits could be recovered there. The next available stock of
>> suitable cable is in Europe, around 35-40 days one-way shipping away.
>> They intend to bridge this time gap via satellite (and I'm sure would
>> welcome a Starlink delegation with a teleport to connect to the
>> international cable, too, especially now that the Australian Navy
>> gave them Omicron along with their aid deliveries).
>> >
>> > I've been in close contact with our volcanology / geophysics
>> community here in NZ, who know the area well. The story of damage to
>> the international cable is now shaping up to be a pretty complex one.
>> What we know thus far is that it was neither the volcano's initial
>> blast nor the subsequent tsunami that killed the cable - the outage
>> began only well after the tsunami had hit. In all probability, it's
>> been a combination of submarine landslides and turbidite waves from a
>> variety of sources that hit hours and possibly many days after the
>> eruption. Finding that a cable piece has moved 5 km TOWARDS the
>> volcano points at an event south of the cable route, and the mix of
>> seafloor visibilities encountered by the Reliance points at there
>> having multiple events from multiple sources. There have been plenty
>> of quakes upwards of M4 and even an M6.2 in the wider area that could
>> have triggered slopes, especially with an extra layer of ash on them.
>> Turbidite waves can travel up to 1000 km, aren't anywhere near as
>> fast as a tsunami, and have long been known to have damaged cables in
>> the past (see B.C. Heezen and M. Ewing, Turbidity currents and
>> submarine slumps, and the 1929 Grand Banks Earthquake, American
>> Journal of Science, v. 250, pp 849-873, December 1952. This quake
>> killed 12 submarine cables over more than 18 hours).
>> >
>> > Meanwhile, there's still limited satellite service in and out of
>> Tonga, but I can confirm that e-mails (even with attachments) make it
>> in and out OK.
>> >
>> > On 18/02/2022 8:27 pm, Mike Puchol wrote:
>> >
>> > Hi Daniel,
>> >
>> > I added it after there was a confirmation on Twitter that SpaceX
>> people were on the ground to set one up, and also, as two /27 blocks
>> (IPv4) have been assigned to Fiji’s capital, under the Sydney POP,
>> and they can be pinged.
>> >
>> > Wether it’s at the teleport or not, unsure, but for simulation, an
>> error of even a few km doesn’t really matter.
>> >
>> > Best,
>> >
>> > Mike
>> > On Feb 18, 2022, 06:04 +0100, Daniel AJ Sokolov <daniel at falco.ca>,
>> wrote:
>> >
>> > On 2022-02-07 at 15:29, Mike Puchol wrote:
>> >
>> > As far as placing a gateway in Fiji, it already has a teleport
>> > facility, which will have power and fibre (unless that one has been
>> > taken out too?). Checkhttps://goo.gl/maps/6BYXf4R17yys7zNe9
>> <Checkhttps://goo.gl/maps/6BYXf4R17yys7zNe9>
>> >
>> >
>> > Hey Mike, you put a "SUVA (Emergency)" ground station on starlink.sx.
>> >
>> > Is that for simulation, or has Starlink actually installed a ground
>> > station in Fidschi by now? Would you have positive confirmation?
>> >
>> > Thank you
>> > Daniel
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>> > --
>> > ****************************************************************
>> > Dr. Ulrich Speidel
>> >
>> > School of Computer Science
>> >
>> > Room 303S.594 (City Campus)
>> >
>> > The University of Auckland
>> > u.speidel at auckland.ac.nz
>> > http://www.cs.auckland.ac.nz/~ulrich/
>> <http://www.cs.auckland.ac.nz/~ulrich>
>> > ****************************************************************
>> >
>> >
>> >
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>>
>> --
>> I tried to build a better future, a few times:
>> https://wayforward.archive.org/?site=https%3A%2F%2Fwww.icei.org
>> <https://wayforward.archive.org/?site=https%3A%2F%2Fwww.icei.org>
>>
>> Dave Täht CEO, TekLibre, LLC
> --
> ****************************************************************
> Dr. Ulrich Speidel
>
> School of Computer Science
>
> Room 303S.594 (City Campus)
>
> The University of Auckland
> u.speidel at auckland.ac.nz
> http://www.cs.auckland.ac.nz/~ulrich/
> ****************************************************************
>
>
>
--
****************************************************************
Dr. Ulrich Speidel
School of Computer Science
Room 303S.594 (City Campus)
The University of Auckland
u.speidel at auckland.ac.nz
http://www.cs.auckland.ac.nz/~ulrich/
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