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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>Some notes in-line below:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From:</b> <span style='font-family:"Malgun Gothic",sans-serif'>구철회</span> <chkoo@kari.re.kr> <br><b>Sent:</b> Monday, April 4, 2022 4:59 PM<br><b>To:</b> sburleig.sb@gmail.com; Dr. Keith L Scott <kscott@mitre.org>; Carlo Caini <carlo.caini@unibo.it>; tomaso.decola@dlr.de; dstanton@keltik.co.uk<br><b>Cc:</b> sis-dtn@mailman.ccsds.org<br><b>Subject:</b> RE: [Sis-dtn] [EXT] Re: Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='word-break:break-all'><span style='font-size:10.0pt;font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>I think Keith thought it as if the last CP was missing.<o:p></o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in;word-break:break-all'><span style='mso-fareast-language:KO'>That’s not how I read “</span><span style='mso-fareast-language:KO'>will send the whole block and then a CP, which will elicit a RS</span><span style='mso-fareast-language:KO'>” but I may have misunderstood.<o:p></o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='font-size:10.0pt;font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>Immediately NACK RS can save time as amount of the difference between current time and the last CP<span lang=KO>’</span>s arrival time. I think the effect can be negligible when bandwidth is very high and a session block length is relatively small, so saving time is order of ms. Of course this effect signifies as big as an RTT when the last CP from a sender is lost during transmission.<o:p></o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in;word-break:break-all'><span style='mso-fareast-language:KO'>Yes, in my example 9.96 seconds, about 2% of a round trip. I think this is what Carlo was saying.<o:p></o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='font-size:10.0pt;font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='font-size:10.0pt;font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>But I do like the way of <span lang=KO>“</span>immediately RS<span lang=KO>”</span>. However the immediately discretionary RS NACK can quickly burn out the return link bandwidth when continuous segment losses are happening while for independent segment loss it will be reasonable. There should be some optimization and I think this concept make LTP be expandable in various space environment.<o:p></o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in;word-break:break-all'><span style='mso-fareast-language:KO'>I worry that this would introduce some additional configuration complexity in a protocol that is already very complex to configure.<o:p></o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='font-size:10.0pt;font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='font-size:10.0pt;font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>Cheol<o:p></o:p></span></p><p class=MsoNormal style='word-break:break-all'><span style='font-size:10.0pt;font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='mso-fareast-language:KO'>From:</span></b><span style='mso-fareast-language:KO'> <a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a> <<a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>> <br><b>Sent:</b> Tuesday, April 5, 2022 4:10 AM<br><b>To:</b> Dr. Keith L Scott <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>>; Carlo Caini <<a href="mailto:carlo.caini@unibo.it">carlo.caini@unibo.it</a>>; <a href="mailto:tomaso.decola@dlr.de">tomaso.decola@dlr.de</a>; </span><span lang=KO style='font-family:"Gulim",serif;mso-fareast-language:KO'>구철회</span><span style='mso-fareast-language:KO'> <<a href="mailto:chkoo@kari.re.kr">chkoo@kari.re.kr</a>>; <a href="mailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk</a><br><b>Cc:</b> <a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b> RE: [Sis-dtn] [EXT] Re: Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p></div></div><p class=MsoNormal><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'>Keith, I think this isn’t quite right.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'>Suppose we’re sending a block that is 1 Megabyte in size, split into 10,000 segments of 100 bytes each. Suppose the OWLT is 240 seconds and the transmission rate is 800 kbps (so 100,000 bytes per second).<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'>Suppose the 3<sup>rd</sup> segment is lost. The receiver will detect this loss when the 4<sup>th</sup> segment is received. That segment will have left the antenna .04 seconds after transmission began, and it will arrive at the receiver 240 seconds later. The receiver will transmit a report segment immediately; let’s ignore the processing and radiation time for issuing the report and say that the report is received at the sender 240 seconds after the arrival of the 4<sup>th</sup> segment – so 480.04 seconds after transmission began. That’s the time at which retransmission can be initiated, right?<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'>Now suppose there is no further data loss. The EOB CP leaves the antenna 10 seconds after transmission began and arrives at the receiver 240 seconds later. The earlier report is still en route to the sender, so the lost segment has not yet been retransmitted. The receiver transmits the CP-triggered report immediately, at 250 seconds after transmission began. That report is received at the sender 240 seconds after arrival of the last segment, so 490 seconds after transmission began; that’s the earliest time at which retransmission can be initiated.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'>So it seems to me that the gap-triggered RS has reduced closure latency by 9.96 seconds, not by 1 RTT. What have I got wrong?<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'>Scott<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='mso-fareast-language:KO'>From:</span></b><span style='mso-fareast-language:KO'> Dr. Keith L Scott <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>> <br><b>Sent:</b> Monday, April 4, 2022 11:50 AM<br><b>To:</b> Carlo Caini <<a href="mailto:carlo.caini@unibo.it">carlo.caini@unibo.it</a>>; <a href="mailto:tomaso.decola@dlr.de">tomaso.decola@dlr.de</a>; <a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>; <a href="mailto:chkoo@kari.re.kr">chkoo@kari.re.kr</a>; <a href="mailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk</a><br><b>Cc:</b> <a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b> Re: [Sis-dtn] [EXT] Re: Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p></div></div><p class=MsoNormal><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'>I think the 'win' would be (comparing a system that generated proactive NACKs vs. a system that generated a CP only at the end of the block):<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'>If there are 10,000 LTP segments and the 3rd segment is lost:<o:p></o:p></span></p><ul style='margin-top:0in' type=disc><li class=MsoPlainText style='mso-list:l0 level1 lfo3'><span style='mso-fareast-language:KO'>The NACK system will nack it “immediately” and elicit a retransmission. Increased latency: about 1 segment.<o:p></o:p></span></li><li class=MsoPlainText style='mso-list:l0 level1 lfo3'><span style='mso-fareast-language:KO'>The non-NACK (call it CP-only) system will send the whole block and then a CP, which will elicit a RS and cause the hole to be filled. Adds 1 RTT (and 1 retransmitted segment) to the block.<o:p></o:p></span></li></ul><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'>So the NACK system can save an RTT. If the loss rate is small (say, the probability of filling all holes in one CP/RS/ReTX event is high) then that’s really all it saves, regardless of the number of losses in the block. If the loss rate is high enough that the expected number of CP/RS/ReTX cycles is higher, the benefit is greater).<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'>So in general if there are N segments and p(segment loss) is p, the number of retransmission rounds should be about -log(N)/log(p) + 1<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='mso-fareast-language:KO'>N = 10,000<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='mso-fareast-language:KO'>P = 0.1<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='mso-fareast-language:KO'># rounds: 5<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='mso-fareast-language:KO'>N = 10,000<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='mso-fareast-language:KO'>P = 0.01<o:p></o:p></span></p><p class=MsoPlainText style='margin-left:.5in'><span style='mso-fareast-language:KO'># rounds: 3<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'>So a proactive-NACK implementation could potentially save about 5 RTTs over a CP-only implementation (sort of a blatent assumption that none of the losses are ‘too close’ to the end, but hey).<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> v/r,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> --keith<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'>On 4/4/22, 1:57 PM, "Carlo Caini" <<a href="mailto:carlo.caini@unibo.it">carlo.caini@unibo.it</a>> wrote:<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Dear all,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> on terrestrial applications LTP segment may arrive out of order, thus NACK could result in unecessary retranmissions; maybe this is not a problem as it is the same in TCP (fast retransmit cannot tolerate more than a disorder of 3 TCP segments).<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> In space, maybe we can assume ordered delivery of LTP segment, thus is true that the LTP receiver could immediately send a NACK as soon as a gap is found (i.e. at the first non contigous claim rfeceived), instead of waiting for the CP, thus saving some time; however, the advantage is limited. If we call radiation time the time necessary to tranmit "on air" a block, we could say that the NACK time gain should be on the evarage of about a half of the radiatrion time. This saved time should however be compared with the RTT, wich is the minimum time necessary for loss recovery. RTT in space is usually >> radiation time, thus the advantage would be negligible. Maybe it could be useful on LEO, where the RTT is small, but we should also have large blocks and slow links...<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Yours,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Carlo<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> ________________________________________<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Da: <a href="mailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de</a> [Tomaso.deCola@dlr.de]<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Inviato: lunedì 4 aprile 2022 17:54<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> A: <a href="mailto:kscott@mitre.org">kscott@mitre.org</a>; <a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>; Carlo Caini; <a href="mailto:chkoo@kari.re.kr">chkoo@kari.re.kr</a>; <a href="mailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk</a><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Cc: <a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Oggetto: RE: [Sis-dtn] [EXT] Re: Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> (I cc again the whole SIS-DTN mailinglist that apparently disappeared from my initial message)<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> At first glance I don’t see a space network configuration in which the LTP segments belonging to a given LTP block could arrived misordered. Perhaps if LTP is operated over UDP also in space (the current spec does not prohibit it to the best of my memory) this could happen but I’d say it is an unlikely configuration.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Tomaso<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> From: Dr. Keith L Scott <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Sent: Montag, 4. April 2022 17:43<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> To: <a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>; Cola, Tomaso de <<a href="mailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de</a>>; <a href="mailto:carlo.caini@unibo.it">carlo.caini@unibo.it</a>; <a href="mailto:chkoo@kari.re.kr">chkoo@kari.re.kr</a>; <a href="mailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk</a><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Subject: Re: [Sis-dtn] [EXT] Re: Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> But for CCSDS applications (and LTPv2 is a CCSDS thing not an IETF thing) maybe we make the assumption that segments are not misordered? Or that the misordering is ‘small’ so that some sort of timer / couter at the receiver could filter out small anomalies? (e.g. hold off sending a NACK for 1,000 segments)?<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> --keith<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> From: "<a href="mailto:sburleig.sb@gmail.com%3cmailto:sburleig.sb@gmail.com%3e">sburleig.sb@gmail.com<mailto:sburleig.sb@gmail.com></a>" <<a href="mailto:sburleig.sb@gmail.com%3cmailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com<mailto:sburleig.sb@gmail.com</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Date: Monday, April 4, 2022 at 11:39 AM<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> To: Tomaso de Cola <<a href="mailto:Tomaso.deCola@dlr.de%3cmailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de<mailto:Tomaso.deCola@dlr.de</a>>>, Keith Scott <<a href="mailto:kscott@mitre.org%3cmailto:kscott@mitre.org">kscott@mitre.org<mailto:kscott@mitre.org</a>>>, "<a href="mailto:carlo.caini@unibo.it%3cmailto:carlo.caini@unibo.it%3e">carlo.caini@unibo.it<mailto:carlo.caini@unibo.it></a>" <<a href="mailto:carlo.caini@unibo.it%3cmailto:carlo.caini@unibo.it">carlo.caini@unibo.it<mailto:carlo.caini@unibo.it</a>>>, Cheol Koo <<a href="mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr">chkoo@kari.re.kr<mailto:chkoo@kari.re.kr</a>>>, Dai Stanton <<a href="mailto:dstanton@keltik.co.uk%3cmailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk<mailto:dstanton@keltik.co.uk</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Subject: RE: [Sis-dtn] [EXT] Re: Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Yes, and for good reason: the design of LTP was originally lifted directly from the CFDP Acknowledged Procedures (and thereupon tweaked a bit). I think the argument against proactively reporting negative DS reception claims was that the missing segments might be already en route but slightly delayed due to transmission over a longer path. In space flight communications this won’t happen because LTP will be running directly over the link; when we test LTP on Earth it is somewhat more likely, as LTP is running directly over UDP/IP and in theory those packets might travel over multiple different routes.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Scott<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> From: <a href="mailto:Tomaso.deCola@dlr.de%3cmailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de<mailto:Tomaso.deCola@dlr.de</a>> <<a href="mailto:Tomaso.deCola@dlr.de%3cmailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de<mailto:Tomaso.deCola@dlr.de</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Sent: Monday, April 4, 2022 8:31 AM<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> To: <a href="mailto:kscott@mitre.org%3cmailto:kscott@mitre.org">kscott@mitre.org<mailto:kscott@mitre.org</a>>; <a href="mailto:sburleig.sb@gmail.com%3cmailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com<mailto:sburleig.sb@gmail.com</a>>; <a href="mailto:carlo.caini@unibo.it%3cmailto:carlo.caini@unibo.it">carlo.caini@unibo.it<mailto:carlo.caini@unibo.it</a>>; <a href="mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr">chkoo@kari.re.kr<mailto:chkoo@kari.re.kr</a>>; <a href="mailto:dstanton@keltik.co.uk%3cmailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk<mailto:dstanton@keltik.co.uk</a>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Subject: RE: [Sis-dtn] [EXT] Re: Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> This looks similar to CFDP-class 2 with retransmission happening in asynchronous mode, isn’t it?<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Regards,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Tomaso<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> From: SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org%3cmailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org<mailto:sis-dtn-bounces@mailman.ccsds.org</a>>> On Behalf Of Dr. Keith L Scott via SIS-DTN<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Sent: Montag, 4. April 2022 17:28<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> To: <a href="mailto:sburleig.sb@gmail.com%3cmailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com<mailto:sburleig.sb@gmail.com</a>>; 'Carlo Caini' <<a href="mailto:carlo.caini@unibo.it%3cmailto:carlo.caini@unibo.it">carlo.caini@unibo.it<mailto:carlo.caini@unibo.it</a>>>; '"</span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>구철회</span><span style='mso-fareast-language:KO'>"' <<a href="mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr">chkoo@kari.re.kr<mailto:chkoo@kari.re.kr</a>>>; 'Keltik' <<a href="mailto:dstanton@keltik.co.uk%3cmailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk<mailto:dstanton@keltik.co.uk</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Cc: <a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org</a>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Subject: Re: [Sis-dtn] [EXT] Re: Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> I think maybe a larger opportunity for improvement would be to have a capability for a receiver to proactively NACK segments WITHOUT having to receive a checkpoint first. That would allow autonomously sending NACKs during the block transmission (thereby filling holes quickly as they are detected) and then relying on the CP/RS/RA exchange to close out the session.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> --keith<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> From: "<a href="mailto:sis-dtn-bounces@mailman.ccsds.org%3cmailto:sis-dtn-bounces@mailman.ccsds.org%3e">sis-dtn-bounces@mailman.ccsds.org<mailto:sis-dtn-bounces@mailman.ccsds.org></a>" <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org%3cmailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org<mailto:sis-dtn-bounces@mailman.ccsds.org</a>>> on behalf of "<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org></a>" <<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Reply-To: "<a href="mailto:sburleig.sb@gmail.com%3cmailto:sburleig.sb@gmail.com%3e">sburleig.sb@gmail.com<mailto:sburleig.sb@gmail.com></a>" <<a href="mailto:sburleig.sb@gmail.com%3cmailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com<mailto:sburleig.sb@gmail.com</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Date: Monday, April 4, 2022 at 11:21 AM<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> To: 'Carlo Caini' <<a href="mailto:carlo.caini@unibo.it%3cmailto:carlo.caini@unibo.it">carlo.caini@unibo.it<mailto:carlo.caini@unibo.it</a>>>, Cheol Koo <<a href="mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr">chkoo@kari.re.kr<mailto:chkoo@kari.re.kr</a>>>, Dai Stanton <<a href="mailto:dstanton@keltik.co.uk%3cmailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk<mailto:dstanton@keltik.co.uk</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Cc: "<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org></a>" <<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Subject: [EXT] Re: [Sis-dtn] Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Hi, guys. I believe we are actually talking about two distinct things here.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> It is true that positive ACKs are required. Positive acknowledgments turn off the retransmission timers for checkpoints, report segments, and cancellation segments.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Separately, the individual "claims" within a report segment might be either positive or negative. I agree with Carlo, but think Cheol is correct that negative claims can yield a small overhead advantage. For any LTP transmission whose scope is from block offset P to Q in which there are N gaps:<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> • If one of the gaps begins at P and another of the gaps ends at Q, then the report must contain either N negative claims or N - 1 positive claims.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> • If no gap begins at P and no gap ends at Q, then the report must contain either N negative claims or N + 1 positive claims.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> • If one of the gaps begins at P or one of the gaps ends at Q, but not both, then the report must contain either N negative claims or N positive claims.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> I would expect the second of these cases to occur more frequently than the other two, assuming AOS/LOS events don't occur during the transmission.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> I don't see how either negative or positive claims processing is simpler or easier, though; the representations are equivalent. Ease of implementation would depend strictly on the manner in which segment information is stored and accessed at the sending and receiving ends of the transmission. I personally found positive claims to be simpler to work with.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Scott<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> -----Original Message-----<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> From: SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org%3cmailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org<mailto:sis-dtn-bounces@mailman.ccsds.org</a>>> On Behalf Of Carlo Caini via SIS-DTN<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Sent: Monday, April 4, 2022 5:47 AM<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> To: "</span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>구철회</span><span style='mso-fareast-language:KO'>" <<a href="mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr">chkoo@kari.re.kr<mailto:chkoo@kari.re.kr</a>>>; Keltik <<a href="mailto:dstanton@keltik.co.uk%3cmailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk<mailto:dstanton@keltik.co.uk</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Cc: <a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org</a>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Subject: Re: [Sis-dtn] Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Dear Cheol,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> let me consider an LTP block with for example 20 non contigous losses, i.e. 20 gaps. The corresponding RS would include either 20 positive claims (if you have a gap at the start or at the end of the block) or 21 cl;aims otherwise.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> With NAK claim you would need 20 megative claims. Is that so different?<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> You can say that it is easier to resend what has been explicietely said is missing, true; however, on the rx side it is easier to say what has been received than what is missing; all things considered, I cannot see any signifiocant advantage by excplicietely declaring gaps instead of received chunks.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Yours,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Carlo<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> ________________________________________<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Da: SIS-DTN [sis-dtn-bounces@mailman.ccsds.org] per conto di "</span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>구철회</span><span style='mso-fareast-language:KO'>" via SIS-DTN [sis-dtn@mailman.ccsds.org]<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Inviato: lunedì 4 aprile 2022 14:20<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> A: Keltik<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Cc: <a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org</a>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Oggetto: Re: [Sis-dtn] Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> I think current LTP spec has positive ACK and negative ACK both. So if it is reversed the result will be the same.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Let me bring below example again. To provide claim inforamtion for retransmission of block 1000-2999,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> <<original-positive ACK>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> lower bound = 0<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> upper bound = 7000<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> negative reception claim count = 2<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> offset = 0 <-- Positive ACK<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> length = 1000 <-- Positive ACK<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> offset = 3000 <-- Positive ACK<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> length = 4000 <-- Positive ACK<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> * Negative ACKs are hidden in separated Positive ACKs.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> <<negative ACK>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> lower bound = 0 <-- Positive ACK<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> upper bound = 7000 <-- Positive ACK<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> negative reception claim count = 1<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> offset = 1000 <-- Negative ACK<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> length = 2000 <-- Negative ACK<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> I think the latter case can work too! Or am I missing something?<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Cheol<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> --------- </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>원본</span><span lang=KO style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>메일</span><span style='mso-fareast-language:KO'> ---------<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>보낸사람</span><span style='mso-fareast-language:KO'> : Keltik <<a href="mailto:dstanton@keltik.co.uk%3cmailto:dstanton@keltik.co.uk">dstanton@keltik.co.uk<mailto:dstanton@keltik.co.uk</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>받는사람</span><span style='mso-fareast-language:KO'> : Vint Cerf <<a href="mailto:vint@google.com%3cmailto:vint@google.com">vint@google.com<mailto:vint@google.com</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>참조</span><span style='mso-fareast-language:KO'> : <<a href="mailto:Felix.Flentge@esa.int%3cmailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int<mailto:Felix.Flentge@esa.int</a>>>, <<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org</a>>>, "</span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>구철회</span><span style='mso-fareast-language:KO'>" <<a href="mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr">chkoo@kari.re.kr<mailto:chkoo@kari.re.kr</a>>> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>받은날짜</span><span style='mso-fareast-language:KO'> : 2022-04-04 (</span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>월</span><span style='mso-fareast-language:KO'>) 19:53:46 </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>제목</span><span style='mso-fareast-language:KO'> : Re: [Sis-dtn] Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing Scott Burleigh and I went through this developing CFDP/LTP three decades ago. Whilst Negative ACKs can be very efficient for bulk data in the delay/disruption environment, protocol directives such as initiation, metadata exchange, end of data, end of transaction, pause, resume etc require positive ACKs. Otherwise the state machines will never close.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Dai<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Sent from my iPhone<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> On 4 Apr 2022, at 11:09, Vint Cerf via SIS-DTN <<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org</a>>> wrote:<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> a system based solely on negative acks will not work.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> v<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> On Mon, Apr 4, 2022 at 6:08 AM Felix Flentge via SIS-DTN <<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org</a>>>> wrote:<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Ah, yes, of course you are right.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> We will look into the negative ACK as part of our LTPv2 prototyping activity.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Regards,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Felix<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> From: "</span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>구철회</span><span style='mso-fareast-language:KO'>" <<a href="mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr">chkoo@kari.re.kr<mailto:chkoo@kari.re.kr<mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr</a>>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> To: <<a href="mailto:Felix.Flentge@esa.int%3cmailto:Felix.Flentge@esa.int%3cmailto:Felix.Flentge@esa.int%3cmailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int<mailto:Felix.Flentge@esa.int<mailto:Felix.Flentge@esa.int%3cmailto:Felix.Flentge@esa.int</a>>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Cc: "<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e%3e">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org><mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e></a>" <<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org</a>>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Date: 04/04/2022 11:58<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Subject: RE: Re: [Sis-dtn] Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Sent by: <a href="mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr">chkoo@kari.re.kr<mailto:chkoo@kari.re.kr<mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> ________________________________<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Hi Felix,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> I think current LTP spec quite works well with negative claim also. Consider below reception claim according to the LTP spec but negative claim.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> lower bound = 0<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> upper bound = 7000<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> negative reception claim count = 1<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> offset = 1000<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> length = 2000<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> it means a receiver is requesting block of segements which starts at 1000 and length is 2000, i.e., 1000 ~ 2999, for retransmission.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> A sender can safely remove 2 blocks, i.e., 0 - 999 and 3000 - 7000. I think it is simpler, lower overhead and *importantly* easier to calculate (acutally no painful for localizing the target segment position).<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Cheol<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> --------- </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>원본</span><span lang=KO style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>메일</span><span style='mso-fareast-language:KO'> ---------<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>보낸사람</span><span style='mso-fareast-language:KO'> : <<a href="mailto:Felix.Flentge@esa.int%3cmailto:Felix.Flentge@esa.int%3cmailto:Felix.Flentge@esa.int%3cmailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int<mailto:Felix.Flentge@esa.int<mailto:Felix.Flentge@esa.int%3cmailto:Felix.Flentge@esa.int</a>>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>받는사람</span><span style='mso-fareast-language:KO'> : "</span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>구철회</span><span style='mso-fareast-language:KO'>" <<a href="mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr">chkoo@kari.re.kr<mailto:chkoo@kari.re.kr<mailto:chkoo@kari.re.kr%3cmailto:chkoo@kari.re.kr</a>>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>참조</span><span style='mso-fareast-language:KO'> : "<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e%3e">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org><mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e></a>" <<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org</a>>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>받은날짜</span><span style='mso-fareast-language:KO'> : 2022-04-04 (</span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>월</span><span style='mso-fareast-language:KO'>) 17:40:24<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> </span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>제목</span><span style='mso-fareast-language:KO'> : Re: [Sis-dtn] Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing Hi Cheol,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> interesting question. One thing I can think of is that the positive claims would allow you to free memory earlier while for negative claims you need to wait until the end of a session.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Regards,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Felix<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> From: "</span><span lang=KO style='font-family:"Malgun Gothic",sans-serif;mso-fareast-language:KO'>구철회</span><span style='mso-fareast-language:KO'> via SIS-DTN" <<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org</a>>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> To: "<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e%3e">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org><mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3e></a>" <<a href="mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org<mailto:sis-dtn@mailman.ccsds.org%3cmailto:sis-dtn@mailman.ccsds.org</a>>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Date: 04/04/2022 10:15<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Subject: [Sis-dtn] Positive reception claim vs. Negative reception claim in LTP Report Segment preparation and processing<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Sent by: "SIS-DTN" <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org%3cmailto:sis-dtn-bounces@mailman.ccsds.org%3cmailto:sis-dtn-bounces@mailman.ccsds.org%3cmailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org<mailto:sis-dtn-bounces@mailman.ccsds.org<mailto:sis-dtn-bounces@mailman.ccsds.org%3cmailto:sis-dtn-bounces@mailman.ccsds.org</a>>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> ________________________________<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Greetings,<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> This is Cheol. I am developing an LTP reference implementation. During reading the LTP specification (RFC-5326), the preparation of reception claim in Report Segment makes me confusing about why it is positive claim not negative claim for segments that were not received successfully (i.e., NAK).<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> For reference, CFDP’s NAK PDU has the negative claim structure when it is requested to report missing PDUs. Does anyone know about the background of choosing the positive claim for NAK operation in LTP?<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> I think negative claim is simpler and more efficient in terms of overhead for sender and receiver both.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> I like to listen experts’ opinion on LTP operation and honestly hope it to be changed in newly coming LTP spec.<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Cheol<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> _______________________________________________<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> SIS-DTN mailing list<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> <a href="mailto:SIS-DTN@mailman.ccsds.org%3cmailto:SIS-DTN@mailman.ccsds.org%3cmailto:SIS-DTN@mailman.ccsds.org%3cmailto:SIS-DTN@mailman.ccsds.org">SIS-DTN@mailman.ccsds.org<mailto:SIS-DTN@mailman.ccsds.org<mailto:SIS-DTN@mailman.ccsds.org%3cmailto:SIS-DTN@mailman.ccsds.org</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> <a href="https://protect2.fireeye.com/v1/url?k=7094fbf6-2f0f91fe-70918a78-ac1f6bdccbcc-0d3d8ac66f4934b2&q=1&e=42cf6e42-dd3d-47b5-ab7c-ec8488c70286&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn%253chttps%3A%2Fprotect2.fireeye.com%2Fv1%2Furl%3Fk%3D933edf14-cca5b51c-933bae9a-ac1f6bdccbcc-93bc8ad36316533d%26q%3D1%26e%3D24a03daf-8e73-4317-a689-3216c529ea83%26u%3Dhttps%253A%252F%252Fmailman.ccsds.org%252Fcgi-bin%252Fmailman%252Flistinfo%252Fsis-dtn%253chttps%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn%253chttps%3A%2Fprotect2.fireeye.com%2Fv1%2Furl%3Fk%3D933edf14-cca5b51c-933bae9a-ac1f6bdccbcc-93bc8ad36316533d%26q%3D1%26e%3D24a03daf-8e73-4317-a689-3216c529ea83%26u%3Dhttps%253A%252F%252Fmailman.ccsds.org%252Fcgi-bin%252Fmailman%252Flistinfo%252Fsis-dtn">https://mailman.ccsds.org/cgi-bin/mailman/listinfo/sis-dtn<https://protect2.fireeye.com/v1/url?k=933edf14-cca5b51c-933bae9a-ac1f6bdccbcc-93bc8ad36316533d&q=1&e=24a03daf-8e73-4317-a689-3216c529ea83&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn<https://mailman.ccsds.org/cgi-bin/mailman/listinfo/sis-dtn%3chttps:/protect2.fireeye.com/v1/url?k=933edf14-cca5b51c-933bae9a-ac1f6bdccbcc-93bc8ad36316533d&q=1&e=24a03daf-8e73-4317-a689-3216c529ea83&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> _______________________________________________<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> SIS-DTN mailing list<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> <a href="mailto:SIS-DTN@mailman.ccsds.org%3cmailto:SIS-DTN@mailman.ccsds.org%3cmailto:SIS-DTN@mailman.ccsds.org%3cmailto:SIS-DTN@mailman.ccsds.org">SIS-DTN@mailman.ccsds.org<mailto:SIS-DTN@mailman.ccsds.org<mailto:SIS-DTN@mailman.ccsds.org%3cmailto:SIS-DTN@mailman.ccsds.org</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> <a href="https://protect2.fireeye.com/v1/url?k=ef21fc5e-b0ba9656-ef248dd0-ac1f6bdccbcc-64b6674f7e819d0e&q=1&e=42cf6e42-dd3d-47b5-ab7c-ec8488c70286&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn%253chttps%3A%2Fprotect2.fireeye.com%2Fv1%2Furl%3Fk%3D60e1ef17-3f7a851f-60e49e99-ac1f6bdccbcc-0dfe5136ab6b73dc%26q%3D1%26e%3Dcce8b1e1-1ec2-4cdd-855b-994c9a3f58c9%26u%3Dhttps%253A%252F%252Fmailman.ccsds.org%252Fcgi-bin%252Fmailman%252Flistinfo%252Fsis-dtn%253chttps%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn%253chttps%3A%2Fprotect2.fireeye.com%2Fv1%2Furl%3Fk%3D60e1ef17-3f7a851f-60e49e99-ac1f6bdccbcc-0dfe5136ab6b73dc%26q%3D1%26e%3Dcce8b1e1-1ec2-4cdd-855b-994c9a3f58c9%26u%3Dhttps%253A%252F%252Fmailman.ccsds.org%252Fcgi-bin%252Fmailman%252Flistinfo%252Fsis-dtn">https://mailman.ccsds.org/cgi-bin/mailman/listinfo/sis-dtn<https://protect2.fireeye.com/v1/url?k=60e1ef17-3f7a851f-60e49e99-ac1f6bdccbcc-0dfe5136ab6b73dc&q=1&e=cce8b1e1-1ec2-4cdd-855b-994c9a3f58c9&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn<https://mailman.ccsds.org/cgi-bin/mailman/listinfo/sis-dtn%3chttps:/protect2.fireeye.com/v1/url?k=60e1ef17-3f7a851f-60e49e99-ac1f6bdccbcc-0dfe5136ab6b73dc&q=1&e=cce8b1e1-1ec2-4cdd-855b-994c9a3f58c9&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> --<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Please send any postal/overnight deliveries to:<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> Vint Cerf<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> 1435 Woodhurst Blvd<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> McLean, VA 22102<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> 703-448-0965<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> until further notice<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> _______________________________________________<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> SIS-DTN mailing list<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span 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href="https://protect2.fireeye.com/v1/url?k=12719fd8-4deaf5d0-1274ee56-ac1f6bdccbcc-05a7930b38352e56&q=1&e=42cf6e42-dd3d-47b5-ab7c-ec8488c70286&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn%253chttps%3A%2Fprotect2.fireeye.com%2Fv1%2Furl%3Fk%3D9ac1f10e-c55a9b06-9ac48080-ac1f6bdccbcc-60db088d278d85f7%26q%3D1%26e%3Dcce8b1e1-1ec2-4cdd-855b-994c9a3f58c9%26u%3Dhttps%253A%252F%252Fmailman.ccsds.org%252Fcgi-bin%252Fmailman%252Flistinfo%252Fsis-dtn%253chttps%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn%253chttps%3A%2Fprotect2.fireeye.com%2Fv1%2Furl%3Fk%3D9ac1f10e-c55a9b06-9ac48080-ac1f6bdccbcc-60db088d278d85f7%26q%3D1%26e%3Dcce8b1e1-1ec2-4cdd-855b-994c9a3f58c9%26u%3Dhttps%253A%252F%252Fmailman.ccsds.org%252Fcgi-bin%252Fmailman%252Flistinfo%252Fsis-dtn">https://mailman.ccsds.org/cgi-bin/mailman/listinfo/sis-dtn<https://protect2.fireeye.com/v1/url?k=9ac1f10e-c55a9b06-9ac48080-ac1f6bdccbcc-60db088d278d85f7&q=1&e=cce8b1e1-1ec2-4cdd-855b-994c9a3f58c9&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn<https://mailman.ccsds.org/cgi-bin/mailman/listinfo/sis-dtn%3chttps:/protect2.fireeye.com/v1/url?k=9ac1f10e-c55a9b06-9ac48080-ac1f6bdccbcc-60db088d278d85f7&q=1&e=cce8b1e1-1ec2-4cdd-855b-994c9a3f58c9&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn</a>>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> _______________________________________________<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> SIS-DTN mailing list<o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> <a href="mailto:SIS-DTN@mailman.ccsds.org%3cmailto:SIS-DTN@mailman.ccsds.org">SIS-DTN@mailman.ccsds.org<mailto:SIS-DTN@mailman.ccsds.org</a>><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'> <a href="https://protect2.fireeye.com/v1/url?k=cad01285-954b788d-cad5630b-ac1f6bdccbcc-4b400b0669265909&q=1&e=42cf6e42-dd3d-47b5-ab7c-ec8488c70286&u=https%3A%2F%2Fmailman.ccsds.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsis-dtn">https://mailman.ccsds.org/cgi-bin/mailman/listinfo/sis-dtn</a><o:p></o:p></span></p><p class=MsoPlainText><span style='mso-fareast-language:KO'><o:p> </o:p></span></p></div></body></html>