On Fri, Jan 14, 2022 at 5:12 AM Jonas Mårtensson <martensson.jo...@gmail.com> wrote: > > > Sure, but given that you probably need a few splices along the way and > > preferably pluggable connectors at both ends the loss budget is not that > > large (assuming an ISP does not want to push its luck and allows for stuff > > like end-users not cleaning the plug diligently before each plugging). > > GPON loss budget is 28 dB and typical insertion losses for 1:32 and 1:64 > splitters are 17 dB and 21 dB. This leaves 11 dB or 7 dB for splices, > connectors and fiber losses. I don't think it's common to have end-users > cleaning and plugging in the fiber, this is done by the ISP technician at > installation. > > > Dslreports has no cue what a link is actually using, all it reports wich > > test profile a user selected, and some users like me ignore the names and > > simply use/recommend the profile with the desired number of flows. Plus > > quite a number of dedidedly metallic access technology are marketed with > > fiber somewhere in the name, potentially confusing users into selecting the > > "wrong" profile (think Fiber to the Cabinet for copper DSL or even > > Hybrid-Fiber-Coax for docsis cable)... in short the abels are nice, but I > > would not read too much inside those. > > I agree with all these points. It may be better to look at ISPs that are > known to only use PON, such as Google Fiber. Here are some recent tests that > all show similar and interesting bufferbloat behaviour on the uplink: > > https://www.dslreports.com/speedtest/70320015
This is gfiber. We didn't so far as I remember get fq_codel going on the uplink there (just the wifi) I don't know anybody anymore over there. > https://www.dslreports.com/speedtest/70346586 > https://www.dslreports.com/speedtest/70346578 > > /Jonas > > On Fri, Jan 14, 2022 at 12:55 PM Sebastian Moeller <moell...@gmx.de> wrote: >> >> Hi Jonas, >> >> >> > On Jan 14, 2022, at 11:44, Jonas Mårtensson <martensson.jo...@gmail.com> >> > wrote: >> > >> > Hi, >> > >> > > getting gpon more right has increasingly been on my mind >> > >> > I think more right is to not turn the fiber into a shared medium in the >> > first place but since gpon is so popular, improving it seems like a nice >> > goal. >> > >> > > Nobody in their right mind is going to hook up 128 terminalt to one OLT >> > > port, I hope... >> > >> > Well, sharing one OLT port between many terminals is kind of the (only) >> > advantage of PON, although split ratios of 32 or 64 are more typical. But >> > often it's the loss budget that limits the ratio. >> >> Sure, but given that you probably need a few splices along the way >> and preferably pluggable connectors at both ends the loss budget is not that >> large (assuming an ISP does not want to push its luck and allows for stuff >> like end-users not cleaning the plug diligently before each plugging). >> >> >> > >> > > Fist question might to be "how broken is GPON/XGPON" to start with, no? >> > >> > Looking at dslreports bufferbloat results for fiber, there are many >> > samples with >250ms latency on the uplink. Unfortunately, this graph >> > doesn't show results for 500Mbit/s or 1Gbit/s services but it's still >> > interesting to look at: >> > >> > https://www.dslreports.com/speedtest/results/bufferbloat?up=1 >> >> Dslreports has no cue what a link is actually using, all it reports >> wich test profile a user selected, and some users like me ignore the names >> and simply use/recommend the profile with the desired number of flows. Plus >> quite a number of dedidedly metallic access technology are marketed with >> fiber somewhere in the name, potentially confusing users into selecting the >> "wrong" profile (think Fiber to the Cabinet for copper DSL or even >> Hybrid-Fiber-Coax for docsis cable)... in short the abels are nice, but I >> would not read too much inside those. >> >> >> > >> > > this thread >> > > https://www.computerbase.de/forum/threads/eigenes-modem-an-ftth-anschluss-via-sfp-gpon-modul.2061989/ >> > > (in German) has some instructions how to get root on one type of SFP >> > > ONU... >> > >> > Thanks, that's an interesting thread. "Hacking" SFP ONUs seems like a >> > popular hobby. Here are some other resources I found: >> > >> > https://github.com/zry98/SFP-GPON-ONU >> > https://github.com/hwti/G-010S-A >> > https://forum.mikrotik.com/viewtopic.php?t=116364&start=300#p771961 >> >> Thanks for the links! >> >> Regards >> Sebastian >> >> >> >> >> >> > >> > > so pulling a testbed together of some sort would be cool, and for that >> > > matter, having a SFP that could go right into a SFP enabled home router >> > > rather than a separate unit seems like a good idea, also >> > >> > Yes, but ideally I guess you would also need some control of the OLT side. >> > You may want to look into the VOLTHA project run by ONF: >> > >> > https://wiki.opennetworking.org/display/COM/VOLTHA >> > >> > /Jonas >> > >> > On Thu, Jan 13, 2022 at 5:29 PM Sebastian Moeller <moell...@gmx.de> wrote: >> > Hi Dave, >> > >> > >> > >> > > On Jan 13, 2022, at 16:59, Dave Taht <dave.t...@gmail.com> wrote: >> > > >> > > On Thu, Jan 13, 2022 at 7:57 AM Sebastian Moeller <moell...@gmx.de> >> > > wrote: >> > >> >> > >> Hi Dave, >> > >> >> > >> >> > >> this thread >> > >> https://www.computerbase.de/forum/threads/eigenes-modem-an-ftth-anschluss-via-sfp-gpon-modul.2061989/ >> > >> (in German) has some instructions how to get root on one type of SFP >> > >> ONU... (I was monitoring that thread for general interest, turns out >> > >> the intel falcon plattform seems somehow based on an ancient OpenWrt) >> > >> >> > >> Regards >> > >> Sebastian >> > > >> > > It's really remarkable how many places are running an ancient openwrt. >> > > Starlink's use was not an abomination, but a persistent reality. Given >> > > how much >> > > chaos calmer I've found, I sometimes wish we'd somehow started the >> > > cerowrt project 2 years earlier. >> > >> > Yes and no. >> > >> > > Then we'd be done by now. >> > >> > Hopefully, but then I would not have noticed the whole thing and >> > would probably not have participated... ;) >> > >> > Regards >> > Sebastian >> > >> > >> > >> > > >> > >> >> > >>> On Jan 13, 2022, at 15:38, Dave Taht <dave.t...@gmail.com> wrote: >> > >>> >> > >>> And a gpon onu >> > >>> >> > >>> https://www.fs.com/products/133619.html >> > >>> >> > >>> On Thu, Jan 13, 2022 at 6:23 AM Sebastian Moeller <moell...@gmx.de> >> > >>> wrote: >> > >>>> >> > >>>> That is similar to what happens in some GPON-ONT SFPs, some run a >> > >>>> full small Linux distribution like OpenWrt inside.... though for >> > >>>> ethernet that is unexpected. >> > >>>> This is also similar to SFP VDSL "modems" which likely run their own >> > >>>> embedded OS as well inside the SFP package (at a time there was even >> > >>>> a PCI VDSL2 "modem" that was actually running its own embedded system >> > >>>> on the PCI board, IIRC, it pretended to the main computer to be an >> > >>>> ethernet NIC). >> > >>>> >> > >>>> Regards >> > >>>> Sebastian >> > >>>> >> > >>>> >> > >>>> >> > >>>>> On Jan 13, 2022, at 15:18, Dave Taht <dave.t...@gmail.com> wrote: >> > >>>>> >> > >>>>> running linux, of course. >> > >>>>> >> > >>>>> https://blog.benjojo.co.uk/post/smart-sfp-linux-inside >> > >>>>> >> > >>>>> -- >> > >>>>> I tried to build a better future, a few times: >> > >>>>> https://wayforward.archive.org/?site=https%3A%2F%2Fwww.icei.org >> > >>>>> >> > >>>>> Dave Täht CEO, TekLibre, LLC >> > >>>>> _______________________________________________ >> > >>>>> Cerowrt-devel mailing list >> > >>>>> Cerowrt-devel@lists.bufferbloat.net >> > >>>>> https://lists.bufferbloat.net/listinfo/cerowrt-devel >> > >>>> >> > >>> >> > >>> >> > >>> -- >> > >>> I tried to build a better future, a few times: >> > >>> https://wayforward.archive.org/?site=https%3A%2F%2Fwww.icei.org >> > >>> >> > >>> Dave Täht CEO, TekLibre, LLC >> > >> >> > > >> > > >> > > -- >> > > I tried to build a better future, a few times: >> > > https://wayforward.archive.org/?site=https%3A%2F%2Fwww.icei.org >> > > >> > > Dave Täht CEO, TekLibre, LLC >> > >> > _______________________________________________ >> > Cerowrt-devel mailing list >> > Cerowrt-devel@lists.bufferbloat.net >> > https://lists.bufferbloat.net/listinfo/cerowrt-devel >> -- I tried to build a better future, a few times: https://wayforward.archive.org/?site=https%3A%2F%2Fwww.icei.org Dave Täht CEO, TekLibre, LLC _______________________________________________ Cerowrt-devel mailing list Cerowrt-devel@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/cerowrt-devel
