We haven't heard much about the starlink ISL links lately. Any sign they are working anywhere yet?
On Sun, Mar 19, 2023 at 7:33 AM Christian von der Ropp via Starlink <[email protected]> wrote: > > All-optical switching could greatly reduce complexity and power > consumption on the satellites at the cost of flexibility. Up to 44 > satellites in an orbital plane would use individual wavelengths which > would be passed on transparently down the daisy chain and only > satellites in range of gateways would convert the optical signals back > into electrical ones, and send them down to earth while they pass a > gateway. This would result in relatively short duty cycles, hence less > power draw per orbit and less heat dissipation issues. > > Actually I've been suspecting that the SDA targets all-optical switching > for the Transport Layer constellation as I don't seen any other > immediate reason for the requirement of their OISL standard to require > wavelength switching within the ITU channel grid for LCTs (see p. 18 of > the OISL 3.0: > https://www.sda.mil/wp-content/uploads/2022/04/SDA-OCT-Standard-v3.0.pdf) > > As a matter of fact tuneable wavelenghts were already required in the > draft version of the OISL standard published in April 2020: > https://twitter.com/Megaconstellati/status/1310336728595562499 > > -Christian > > Am 19.03.2023 um 16:16 schrieb Brandon Butterworth via Starlink: > > On Sat Mar 18, 2023 at 03:19:49PM -0700, Dave Taht via Starlink wrote: > >> Today, this about google's mems switching tech hit, > > They've been talking about it since last year, seems to have got > > a hype bump recently. > > > > Who expected circuit switching to make a comeback? > > > >> I keep wondering where else it could be applied. > > They've been used for a long time, eg almost 20 years ago - > > https://archive.nanog.org/meetings/nanog32/presentations/zwart.pdf > > > > There is a goal of optical packet switching, until then you're > > limited to where there are limited flows of long enough duration > > to make the change from packet to circuit switching viable. So mostly > > automated testing. > > > > I've dabbled with the idea in an archive use case where very few of > > a large set of storage nodes need to connect to a moderate number > > of servers. For some cases we could have zero switches. The goal was > > a mostly dark infrastructure and many 1000s of storage nodes, > > removing the switches saves a lot of power. > > > > Commercial optical switches are expensive so I was looking at > > making an optical strowger as I wanted a high fan out not > > large n^2. > > > > In the mobile world they are looking at doing flexible bandwidth > > per node with coherent optics over gpon fibre plant, allocating > > variable amounts of spectrum to each, which could be adapted to a > > similar circuit model. It'd be no use to google as they want the > > full bandwidth between each node but as dwdm coherent optic costs > > come down you could imagine doing the same with a full channel > > between each pair, so like a conventional WSS but cheaper. If it > > wasn't for the optics cost I suspect they'd have done that reducing > > switching time to a channel change. > > > > brandon > > _______________________________________________ > > Starlink mailing list > > [email protected] > > https://lists.bufferbloat.net/listinfo/starlink > > _______________________________________________ > Starlink mailing list > [email protected] > https://lists.bufferbloat.net/listinfo/starlink -- Come Heckle Mar 6-9 at: https://www.understandinglatency.com/ Dave Täht CEO, TekLibre, LLC _______________________________________________ Starlink mailing list [email protected] https://lists.bufferbloat.net/listinfo/starlink
