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implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.10 Precedence: list Subject: [Starlink] Re: Dissecting Starlink: head-drop queuing, AQM, and flow dynamics (SIGCOMM '26) List-Id: "Starlink has bufferbloat. Bad." Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: yes, and the starlink router is the device under test (dut) and we control = both ends ;-) -- J Pan, UVic CSc, ECS566, 250-472-5796 (NO VM), Pan@UVic.CA, Web.UVic.CA/~pa= n ________________________________________ From: Nitinder Mohan Sent: Wednesday, July 22, 2026 8:21 AM To: Jianping Pan; Kathleen Nichols Cc: starlink@lists.bufferbloat.net; Hendrik Cech Subject: Re: [Starlink] Re: Dissecting Starlink: head-drop queuing, AQM, an= d flow dynamics (SIGCOMM '26) Hi J, I didn't quite get it. Do you have a way of isolating traffic only in Starl= ink router (so before it is sent to the dishy)? Get Outlook for Android ________________________________ From: Jianping Pan Sent: Wednesday, 22 July 2026 17:18:55 To: Kathleen Nichols ; Nitinder Mohan Cc: starlink@lists.bufferbloat.net ; Hendri= k Cech Subject: Re: [Starlink] Re: Dissecting Starlink: head-drop queuing, AQM, an= d flow dynamics (SIGCOMM '26) we can measure the traffic in and out of the starlink router to profile it = for you. cheers. -j -- J Pan, UVic CSc, ECS566, 250-472-5796 (NO VM), Pan@UVic.CA, Web.UVic.CA/~pa= n ________________________________________ From: Nitinder Mohan via Starlink Sent: Wednesday, July 22, 2026 7:26 AM To: Kathleen Nichols Cc: starlink@lists.bufferbloat.net; Hendrik Cech Subject: [Starlink] Re: Dissecting Starlink: head-drop queuing, AQM, and fl= ow dynamics (SIGCOMM '26) Hi Kathie, You are, indeed, absolutely correct. Our takeaway largely is that the AQM b= eing used is proprietary, it resembles A-RED and CoDEL at some instances bu= t its not a 1:1 match. SpaceX also confirms that there is some =93inspirati= on". We have a discussion on this in sec 4.3 on page 8. Best, Nitinder > On 22 Jul 2026, at 15:49, Kathleen Nichols via Starlink wrote: > > > This is interesting work, thanks. But I want to point out that, if indeed= the "Loss frequency grows with queue occupancy" that isn't CoDel which inc= reases loss frequency with a persistent sojourn delay. (A large point of Co= Del was to get away from queue occupancy as a congestion signal.) > > Kathie > > On 7/22/26 2:00 AM, Nitinder Mohan via Starlink wrote: > ... >> * There is a real AQM that deliberately drops to control occupancy. = The uplink is aggressive and holds flows below a quarter of physical capaci= ty. The downlink is more permissive. Loss frequency grows with queue occupa= ncy, and the load-dependent profile looks closer to CoDel or adaptive RED t= han fixed RED. > ... > > _______________________________________________ > Starlink mailing list -- starlink@lists.bufferbloat.net > To unsubscribe send an email to starlink-leave@lists.bufferbloat.net _______________________________________________ Starlink mailing list -- starlink@lists.bufferbloat.net To unsubscribe send an email to starlink-leave@lists.bufferbloat.net