From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yb1-xb33.google.com (mail-yb1-xb33.google.com [IPv6:2607:f8b0:4864:20::b33]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 9708E3CB38; Tue, 21 Mar 2023 13:22:14 -0400 (EDT) Received: by mail-yb1-xb33.google.com with SMTP id j7so18061162ybg.4; Tue, 21 Mar 2023 10:22:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1679419334; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=SZ+arvTPiAFnH4IzYPQzXPGKpPb3td+KPCttvQQCHMc=; b=ZRFIR6AtXxt9VRprksQI8JpirkYhkCn1s0cBPV+8nBRbMu8ClHiO+huo7q7G1/Y2r+ wqU3lJgXM96OKssGj+uzNPnFbyugn1gUzih7Vaog9SS4GD48qCiIp7UpIHgQTp1jVvJZ mcaLWihcCCxY/7BZ+CY3CHTKlmo+1cP7DGmwcC+8X9+iTQcz/bXpfGYHluihfJeQQBoL PQDdgLw+OcfP29n+KxHOvtFdfk5wJGAGziqgekw2skaGXLl9uY8lRQZ5jEhxNkwCJurI EMsNIRFO/bweIra2TMv2weifql4e5yOELkAMrsxUh9862rZyKQUCuYyp8VoEhka1qvPi 0VTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679419334; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=SZ+arvTPiAFnH4IzYPQzXPGKpPb3td+KPCttvQQCHMc=; b=Tj1K+7pJcU5wc7rFjwyu0DH3EFB4E9NfjyQ6QlZcuXz2qNZFgYxJc0eM4HaMXf2+xy 4+E9t5Tx4BQjkIjlXoUByd9p7pFA2eGTUdNm0+eQzRLtCwbOd2VZYQmQfbDWd86s3LL2 8jpkgpe+iSoVvIncqVnu3LK82y4bUrY0s5mthAGflOJVUKTg6Kw099hB9I98k3Z1lorv gm51ZkW5h9rVylXolYyH7YpC2NQ3juZ+qnPsfNQaSAndmbA6g+P9bV8Q7zvwnYwV0lFT IHgx/OgaAIiS73Cp/CfwpBYPFyd+6wIg4Y2BIVPTtY6SRFv1C3JBzxQdXclb3YotMCvh g5yw== X-Gm-Message-State: AAQBX9fzv0W6k1bLIpdMXDSVRdLjapd6Gbik3s4f2iLk90uhIlU5FLnM TASN1bH09B2cnEls73tyC0fc922Py41ySq7lmrg= X-Google-Smtp-Source: AKy350Z7WWvmfoSvIHW4/aX9V1cWjaHjl7p/2C4nFHPoLMeVUfjSqAGyksa8ERL8ApQuS5QiybuqmfOOlS5zszI9020= X-Received: by 2002:a05:6902:1023:b0:b6b:841a:aae4 with SMTP id x3-20020a056902102300b00b6b841aaae4mr1613817ybt.12.1679419333851; Tue, 21 Mar 2023 10:22:13 -0700 (PDT) MIME-Version: 1.0 References: <20230321001019.GA4531@sunf68.rd.bbc.co.uk> <46A0D5B3-FFAA-40A3-B94C-6D01C99D92EB@gmail.com> In-Reply-To: From: dan Date: Tue, 21 Mar 2023 11:22:03 -0600 Message-ID: To: Sebastian Moeller Cc: Rich Brown , Frantisek Borsik , bloat , libreqos Content-Type: multipart/alternative; boundary="000000000000d2c18105f76c48cf" Subject: Re: [Bloat] [Starlink] Annoyed at 5/1 Mbps... X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 21 Mar 2023 17:22:14 -0000 --000000000000d2c18105f76c48cf Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable GPON is TDMA so the latency is going to be at a minimum the RTT * connected ONUs, vs DSL which is a fixed ratio/scheduler. Standard GPON deployments are typically well over 1 second to the OLT. Not that it's bad or anything, but in comparison GPON has very 'wireless' like best case latency but without the wireless variances. On Tue, Mar 21, 2023 at 6:31=E2=80=AFAM Sebastian Moeller = wrote: > I have to push back gently on this... > > XG(S)-PON is gross 10Gbps (after FEC you are left with around 8,6 Gbps), > Noki's proprietary (aka not ITU) @% Gbps PON seems to be abbreviated > 25GS-PON. > > Now XGS-PON allows maximally 128 end-nodes in the tree, so: > 8600/128 =3D 67.18 Mbps/subscriber > > unless the ISPs royally screwed up the configuration there should be a CI= R > per subscriber of around 60 Mbps. So setting your cake shaper to 50 Mbps > shpuld give you: > a) 10 times the throughput of the 5/1 Mbps DSL (ignoring overhead > compensation for a change, which likely will be in favor of PON) > b) decent low latency, round robin delay for full MTU packets between 128 > active nodes would be: > packet/sec: ((8.6 * 1000^3)/(1500*8)) =3D 716666.666667 > millisec/packet: 1000 / ((8.6 * 1000^3)/(1500*8)) =3D > 0.00139534883721 > round-robin delay 128: 128 * 1000 / ((8.6 * 1000^3)/(1500*8)) =3D > 0.178604651163 milliseconds... > > DSL uses a 4KHz clock so 1000/4000 =3D 0.25 millisecond quantizat= ion > So XGS-PON has at least theoretical potential to deliver lower latency > than DSL, but the details depend on if/how packets are aggregated. HOWEVE= R > the 125=C2=B5sec GPON frames can be shared between different ONUs in upst= ream > and downstream direction... so these are not a hard quantisation but more > the interval between control information required for the access grant > cycle... > > c) robustness against RF noise sources and electricity/lightning > > So I am not su sure I would prefer the 5/1 (A)DSL over a PON... > > That however is orthogonal to me preferring a competent ISP that takes > care of keeping latency under load at bay. > > > > > On Mar 21, 2023, at 12:26, Rich Brown via Starlink < > starlink@lists.bufferbloat.net> wrote: > > > > > > > >> On Mar 21, 2023, at 1:21 AM, Frantisek Borsik via Rpm < > rpm@lists.bufferbloat.net> wrote: > >> > >> Now, I hope to really piss You off with the following statement :-P > but: > >> > >> even sub 5/1 Mbps =E2=80=9Cbroadband=E2=80=9D in Africa with bufferblo= at fixed on as > many hops along the internet journey from a data center to the customers > mobile device (or with just LibreQoS middle box in the ISP=E2=80=99s netw= ork) is > feeling way better than 25Gbps XG-PON. The only time the XG-PON guy could > really feel like a king of the world would be during his speedtest. > > > > Nope. Sorry - this doesn't piss me off :-) It's just true. > > > > - 7mbps/768kbps DSL with an IQrouter works fine for two simultaneous > Zoom conferences. (Even though no one would think that it's fast.) > > - I recommend people on a budget drop their ISP speed so they can affor= d > a router that does SQM > https://forum.openwrt.org/t/so-you-have-500mbps-1gbps-fiber-and-need-a-ro= uter-read-this-first/90305/40 > > Even simpler, even on a 100Gbps link nobody stops you from settin= g > your shaper to 50/10 if that is all your router can deliver (and I agree = if > there are cheaper plans closer to the 50/10 it makes economic sense to > scale down the plan)... > > > > > > The people that get annoyed are those who just upgraded to 1Gbps servic= e > and still are getting fragged in their games. > > > > Rich > > _______________________________________________ > > Starlink mailing list > > Starlink@lists.bufferbloat.net > > https://lists.bufferbloat.net/listinfo/starlink > > --000000000000d2c18105f76c48cf Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
GPON is TDMA so the latency is going to be at a minimum th= e RTT * connected ONUs, vs DSL which is a fixed ratio/scheduler.=C2=A0=C2= =A0

Standard GPON deployments are typically well over 1 second to th= e OLT.=C2=A0 Not that it's bad or anything, but in comparison GPON has = very 'wireless' like best case latency but without the wireless var= iances.

On Tue, Mar 21, 2023 at 6:31=E2=80=AFAM Sebastian Moeller <moeller0@gmx.de> wrote:
I have to push back gently on t= his...

XG(S)-PON is gross 10Gbps (after FEC you are left with around 8,6 Gbps), No= ki's proprietary (aka not ITU) @% Gbps PON seems to be abbreviated 25GS= -PON.

Now XGS-PON allows maximally 128 end-nodes in the tree, so:
8600/128 =3D 67.18 Mbps/subscriber

unless the ISPs royally screwed up the configuration there should be a CIR = per subscriber of around 60 Mbps. So setting your cake shaper to 50 Mbps sh= puld give you:
a) 10 times the throughput of the 5/1 Mbps DSL (ignoring overhead compensat= ion for a change, which likely will be in favor of PON)
b) decent low latency, round robin delay for full MTU packets between 128 a= ctive nodes would be:
=C2=A0 =C2=A0 =C2=A0 =C2=A0 packet/sec: ((8.6 * 1000^3)/(1500*8)) =3D 71666= 6.666667
=C2=A0 =C2=A0 =C2=A0 =C2=A0 millisec/packet: 1000 / ((8.6 * 1000^3)/(1500*8= )) =3D 0.00139534883721
=C2=A0 =C2=A0 =C2=A0 =C2=A0 round-robin delay 128: 128 * 1000 / ((8.6 * 100= 0^3)/(1500*8)) =3D 0.178604651163 milliseconds...

=C2=A0 =C2=A0 =C2=A0 =C2=A0 DSL uses a 4KHz clock so 1000/4000 =3D 0.25 mil= lisecond quantization
So XGS-PON has at least theoretical potential to deliver lower latency than= DSL, but the details depend on if/how packets are aggregated. HOWEVER the = 125=C2=B5sec GPON frames can be shared between different ONUs in upstream a= nd downstream direction... so these are not a hard quantisation but more th= e interval between control information required for the access grant cycle.= ..

c) robustness against RF noise sources and electricity/lightning

So I am not su sure I would prefer the 5/1 (A)DSL over a PON...

That however is orthogonal to me preferring a competent ISP that takes care= of keeping latency under load at bay.



> On Mar 21, 2023, at 12:26, Rich Brown via Starlink <starlink@lists.bufferb= loat.net> wrote:
>
>
>
>> On Mar 21, 2023, at 1:21 AM, Frantisek Borsik via Rpm <rpm@lists.bufferblo= at.net> wrote:
>>
>> Now, I hope to really piss You off with the following statement=C2= =A0 :-P but:
>>
>> even sub 5/1 Mbps =E2=80=9Cbroadband=E2=80=9D in Africa with buffe= rbloat fixed on as many hops along the internet journey from a data center = to the customers mobile device (or with just LibreQoS middle box in the ISP= =E2=80=99s network) is feeling way better than 25Gbps XG-PON. The only time= the XG-PON guy could really feel like a king of the world would be during = his speedtest.
>
> Nope. Sorry - this doesn't piss me off :-) It's just true. >
> - 7mbps/768kbps DSL with an IQrouter works fine for two simultaneous Z= oom conferences. (Even though no one would think that it's fast.)
> - I recommend people on a budget drop their ISP speed so they can affo= rd a router that does SQM https://forum.openwrt.org/t/so-you-have-500mbps= -1gbps-fiber-and-need-a-router-read-this-first/90305/40

=C2=A0 =C2=A0 =C2=A0 =C2=A0 Even simpler, even on a 100Gbps link nobody sto= ps you from setting your shaper to 50/10 if that is all your router can del= iver (and I agree if there are cheaper plans closer to the 50/10 it makes e= conomic sense to scale down the plan)...


>
> The people that get annoyed are those who just upgraded to 1Gbps servi= ce and still are getting fragged in their games.
>
> Rich
> _______________________________________________
> Starlink mailing list
> St= arlink@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/starlink<= /a>

--000000000000d2c18105f76c48cf--