From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailout2.rbg.tum.de (mailout2.rbg.tum.de [IPv6:2a09:80c0::202]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id E342D3B2A4 for ; Thu, 14 Jul 2022 08:49:14 -0400 (EDT) Received: from mailrelay1.rbg.tum.de (mailrelay1.in.tum.de [IPv6:2a09:80c0:254::14]) by mailout2.rbg.tum.de (Postfix) with ESMTPS id EB44F4C02D6; Thu, 14 Jul 2022 14:49:11 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=in.tum.de; s=20220209; t=1657802951; bh=so/cusO2cXxXtDZ435oQJB7Ml/oYsgNRbg3NkMmBdF8=; h=Date:From:To:Cc:In-Reply-To:References:Subject:From; b=D3OET077gzMM3HAvat4X26FHD+kU+5PBGJ7sGqO0Rjzw30lU8rMFqWlIR+qjwBAyJ h6hUaJUQMQ7LG+AyvqWGMEsv37mLwr1zzOVsVVaF9+rsBKuR/SFnBVVoQxM2tiIZVP fLosANxbQNKKQKqB4CjwoH9b6Qi7/UlUoQzcZjwUrbCyIjO+qlf+1pOuIJCGt7N1p1 69yj/oPO46G6qrfU588lqja9Jy1kBY67d/H8yW+RUORZZWoU3lYgYITwx/EyPB6WzQ tgi6vJo7k6BGgDZHEM8pJZm27cQv/CVYcQGLVbYxuhTF4xY0KnPwXbi1iFIRuIKqHR nl1rVUjmzhIqg== Received: by mailrelay1.rbg.tum.de (Postfix, from userid 112) id E89CA5B5; Thu, 14 Jul 2022 14:49:11 +0200 (CEST) Received: from mailrelay1.rbg.tum.de (localhost [127.0.0.1]) by mailrelay1.rbg.tum.de (Postfix) with ESMTP id C14F5DCD; Thu, 14 Jul 2022 14:49:11 +0200 (CEST) Received: from mail.in.tum.de (mailproxy.in.tum.de [IPv6:2a09:80c0::78]) by mailrelay1.rbg.tum.de (Postfix) with ESMTPS id BE9A05B5; Thu, 14 Jul 2022 14:49:11 +0200 (CEST) Received: by mail.in.tum.de (Postfix, from userid 112) id BB9764A04E7; Thu, 14 Jul 2022 14:49:11 +0200 (CEST) Received: (Authenticated sender: mohan) by mail.in.tum.de (Postfix) with ESMTPSA id 4D8124A02BF; Thu, 14 Jul 2022 14:49:11 +0200 (CEST) (Extended-Queue-bit xtech_qn@fff.in.tum.de) Date: Thu, 14 Jul 2022 14:49:06 +0200 From: Nitinder Mohan To: Mike Puchol Cc: Dave Taht via Starlink Message-ID: In-Reply-To: <0C0F0D5F-7CF6-412A-AD1A-392323ADB2FB@gmx.de> References: <20220713173602.0582c9b3@spidey.rellim.com> <92n4s129-6r15-7q75-7293-qpo73q298srn@ynat.uz> <841ca6dc-d6d3-46ab-87c0-d6bcaa31533b@Spark> <42D3F3C5-C1B3-48EA-8C45-2540ACD787E4@gmx.de> <0C0F0D5F-7CF6-412A-AD1A-392323ADB2FB@gmx.de> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="62d010c7_4296fab6_2a3f" Subject: Re: [Starlink] starlink at sea X-BeenThere: starlink@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Starlink has bufferbloat. Bad." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 14 Jul 2022 12:49:15 -0000 --62d010c7_4296fab6_2a3f Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Hi Mike, Do you happen to have a tool that can extract the current uplink channel = of Starlink and (more importantly) which staellite it is connected to at = any given time=3F I wanted to track the handovers in Starlink and try to = find its impact on network performance but cannot seem to get those value= s.=C2=A0 Thanks and Regards Nitinder Mohan Technical University Munich (TUM) https://www.nitindermohan.com/ =46rom:=C2=A0Sebastian Moeller via Starlink Reply:=C2=A0Sebastian Moeller Date:=C2=A014. July 2022 at 14:35:16 To:=C2=A0Mike Puchol Cc:=C2=A0Dave Taht via Starlink Subject:=C2=A0 Re: =5BStarlink=5D starlink at sea =20 Hi Mike. Thanks a lot. This is intersting. > On Jul 14, 2022, at 14:02, Mike Puchol wrote: > =20 > The uplink is an O=46DM signal with 128 subcarriers, looking at the sig= nal in the time domain reveals a frame length corresponding to 14% (from = memory, 1,1 us frame vs 6.7 us pause). I have two terminals 1 meter apart= and they can each achieve 30 Mbps at the same time over the same uplink = channel. I would expect the satellite to assign a particular set of slots= to a terminal. So assuming the 30 Mbps being gross rate and not measured goodput: 30Mbps -> 30 / (1.1/(6.7+1.1)) =3D 212.73 Mb/s while actively sending, an= d =20 1000000=C2=B5s/s / (6.7+1.1)=C2=B5s =3D 128205.128205 slots/sec (30 / (1.1/(6.7+1.1))) * 1000=5E2 / (1000000 / (6.7+1.1)) =3D 1659.27 bit= s/slot 1659.27/8 =3D 207.41 Bytes/slot with 128 subcarriers that would be approximately an average =20 1659.27/128 =3D 12.96 or =7E 13 bit/subcarrier =20 if all carriers are loaded equally (which is unlikely, I expect some re-a= rrangement ot bits between subcarriers to account for different levels of= noise and what not). > If there are any O=46DM blind analysis experts in the room, shout=21 Please do=21 Regards Sebastian > =20 > Best, > =20 > Mike > On Jul 14, 2022, 13:33 +0200, Sebastian Moeller , wr= ote: >> Hi Mike, >> =20 >>> On Jul 14, 2022, at 13:15, Mike Puchol via Starlink wrote: >>> =20 >>> On the multiple terminals, I have verified that the duty cycle of a c= onsumer terminal is 14%, thus, you could have 7 terminals on a single upl= ink channel with some guard time. >> =20 >> Could you elaborate how that works.how the terminals will be interleav= ed in that situation=3F >> =20 >> Regards >> Sebastian >> =20 >> =20 >>> I have seen 30 Mbps up, so you=E2=80=99d be able to push 210 Mbps in = uplink, or a spectral efficiency of about 3.4 bps/Hz. >> =20 =5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F= =5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F Starlink mailing list Starlink=40lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/starlink --62d010c7_4296fab6_2a3f Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
Hi Mike,

Do you happen to have a tool that can= extract the current uplink channel of Starlink and (more importantly) wh= ich staellite it is connected to at any given time=3F I wanted to track t= he handovers in Starlink and try to find its impact on network performanc= e but cannot seem to get those values. 

Thanks and Regards
=
Nitinder Moh= an
Technical University Munich (T= UM)

=46rom: = Sebastian Moeller via Starlink <starlink=40lists= .bufferbloat.net>
Reply: S= ebastian Moeller <moel= ler0=40gmx.de>
Date: 14. J= uly 2022 at 14:35:16
To: M= ike Puchol <mike=40st= arlink.sx>
Cc: Dave Taht v= ia Starlink <starlink=40lists.bufferbloat.net>
Subject:  Re: =5BStarlink=5D starlink at sea

=
Hi Mike.

Thanks a lot. This is intersting.

= > On Jul 14, 2022, at 14:02, Mike Puchol <mike=40starlink.sx> wr= ote:
>
> The uplink is an O=46DM signal with 128 subcarriers= , looking at the signal in the time domain reveals a frame length corresp= onding to 14% (from memory, 1,1 us frame vs 6.7 us pause). I have two ter= minals 1 meter apart and they can each achieve 30 Mbps at the same time o= ver the same uplink channel. I would expect the satellite to assign a par= ticular set of slots to a terminal.

So assuming the 30 Mbps being= gross rate and not measured goodput:

30Mbps -> 30 / (1.1/(6.7+= 1.1)) =3D 212.73 Mb/s while actively sending, and
1000000=C2=B5s/s / = (6.7+1.1)=C2=B5s =3D 128205.128205 slots/sec
(30 / (1.1/(6.7+1.1))) *= 1000=5E2 / (1000000 / (6.7+1.1)) =3D 1659.27 bits/slot 1659.27/8 =3D 207= .41 Bytes/slot

with 128 subcarriers that would be approximately an= average

1659.27/128 =3D 12.96 or =7E 13 bit/subcarrier

i= f all carriers are loaded equally (which is unlikely, I expect some re-ar= rangement ot bits between subcarriers to account for different levels of = noise and what not).


> If there are any O=46DM blind analys= is experts in the room, shout=21

Please do=21
Regards
Seba= stian

>
> Best,
>
> Mike
> On Jul 14,= 2022, 13:33 +0200, Sebastian Moeller <moeller0=40gmx.de>, wrote:>> Hi Mike,
>>
>>> On Jul 14, 2022, at 13:1= 5, Mike Puchol via Starlink <starlink=40lists.bufferbloat.net> wrot= e:
>>>
>>> On the multiple terminals, I have ver= ified that the duty cycle of a consumer terminal is 14%, thus, you could = have 7 terminals on a single uplink channel with some guard time.
>= >
>> Could you elaborate how that works.how the terminals wi= ll be interleaved in that situation=3F
>>
>> Regards>> Sebastian
>>
>>
>>> I have see= n 30 Mbps up, so you=E2=80=99d be able to push 210 Mbps in uplink, or a s= pectral efficiency of about 3.4 bps/Hz.
>>

=5F=5F=5F=5F=5F= =5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F= =5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F
Starlink mailing l= ist
Starlink=40lists.bufferbloat.net
https://lists.bufferbloat.net/= listinfo/starlink
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