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<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Hi Keith,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">I’m getting now a bit confused about what we mean with v1 and v2. I thought that v1 was the current LTP book with some minor adjustments object of the 5-year review, whereas the v2 is the one implying
modifications at header level, orange book, monochrome blocks, etc…<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Where is in fact the border between the two?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Tomaso<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> Dr. Keith L Scott <kscott@mitre.org>
<br>
<b>Sent:</b> Montag, 25. Oktober 2021 14:51<br>
<b>To:</b> Cola, Tomaso de <Tomaso.deCola@dlr.de>; Felix.Flentge@esa.int<br>
<b>Cc:</b> Gifford, Kevin <kevin.gifford@colorado.edu>; sis-dtn@mailman.ccsds.org; sis-dtn-bounces@mailman.ccsds.org; peter.m.shames@jpl.nasa.gov; jordan.l.torgerson@jpl.nasa.gov<br>
<b>Subject:</b> Re: [Sis-dtn] [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">My plan (before Orange showed up) was to tie off the LTPv2 stuff at this meeting and to move out with implementation. We could start Red-1 agency review by the end of this CY, and I’ve got my v1 implementation that MITRE
is updating to match the current (not yet including Orange) draft, so if somebody can update another implementation we could do the interoperability testing next summer if the agency reviews go well. If that other implementation is ION, I’ve still got (somewhere,
I hope) all the interoperability tests we did for v1; downselecting those to remove the ones that test things not in v2 and adding something to exercise the field length selector and re-running the test scripts wouldn’t be a lot of work.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">It is my understanding that a completed spec for gateway would be a Really Good Thing, AND, the longer we push off LTPv2, the more chance there is that more LTPv1 stuff will be deployed which will make it more difficult
to change later.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> --keith<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span lang="EN-US" style="font-size:12.0pt;color:black">From:
</span></b><span lang="EN-US" style="font-size:12.0pt;color:black"><a href="mailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de</a> <<a href="mailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de</a>><br>
<b>Date: </b>Monday, October 25, 2021 at 8:02 AM<br>
<b>To: </b><a href="mailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int</a> <<a href="mailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int</a>><br>
<b>Cc: </b>Gifford, Kevin <<a href="mailto:kevin.gifford@colorado.edu">kevin.gifford@colorado.edu</a>>,
<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a> <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>>, Dr. Keith L Scott <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>>,
<a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a> <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a>>,
<a href="mailto:peter.m.shames@jpl.nasa.gov">peter.m.shames@jpl.nasa.gov</a> <<a href="mailto:peter.m.shames@jpl.nasa.gov">peter.m.shames@jpl.nasa.gov</a>>,
<a href="mailto:jordan.l.torgerson@jpl.nasa.gov">jordan.l.torgerson@jpl.nasa.gov</a> <<a href="mailto:jordan.l.torgerson@jpl.nasa.gov">jordan.l.torgerson@jpl.nasa.gov</a>><br>
<b>Subject: </b>RE: [Sis-dtn] [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2<o:p></o:p></span></p>
</div>
<p class="MsoNormal">Hi Felix,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Given the usual preparation/review process of CCSDS blue books, I guess the LTPv2 or LTP+ one won’t be ready before 2023, if we take into account the agency review, interoperability, yellow book etc. Would year 20223 be more in line with
the plan from ESA? In any case, I expect that the interim and final outcomes of the activity you have just mentioned will be used as input to the CCSDS standardisation path for this book, isn’t it?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For the LTPv1/v2 discussion, I think something more will be discussed today and in any case will be administered by Keith.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best Regards,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Tomaso<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a>>
<b>On Behalf Of </b><a href="mailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int</a><br>
<b>Sent:</b> Montag, 25. Oktober 2021 12:38<br>
<b>To:</b> <a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br>
<b>Cc:</b> Gifford, Kevin <<a href="mailto:kevin.gifford@colorado.edu">kevin.gifford@colorado.edu</a>>; SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a>>; Shames, Peter M (US 312B) <<a href="mailto:peter.m.shames@jpl.nasa.gov">peter.m.shames@jpl.nasa.gov</a>>;
Torgerson, J. Leigh(US 332C) <<a href="mailto:jordan.l.torgerson@jpl.nasa.gov">jordan.l.torgerson@jpl.nasa.gov</a>><br>
<b>Subject:</b> Re: [Sis-dtn] [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Hi,</span>
<br>
<br>
<span style="font-size:10.0pt;font-family:"Arial",sans-serif">I don't see a major issue of having LTPv1 and LTPv2 (or LTP+ ?) as Blue Books for a longer period of time as they are 'only' link layer protocols and these links will have to be designed for interoperability
anyway (frequencies, coding & modulation, data link layer protocol, ...). Furthermore, we may have really separate domains with optical / high-rate RF Earth observation downlinks and Gateway/LunaNet/Moonlight. Of course, in the long term, we should converge
to a single protocol.</span> <br>
<br>
<span style="font-size:10.0pt;font-family:"Arial",sans-serif">Also, I would prefer to have a bit longer time frame for the LTP+ definition. ESA will kick-off a dedicated activity for the definition and prototyping (including hardware implementation) very soon
but it will take until end of 2022 to finish. This would give us also a reference implementation for the interoperability testing.</span>
<br>
<br>
<span style="font-size:10.0pt;font-family:"Arial",sans-serif">Regards,</span> <br>
<span style="font-size:10.0pt;font-family:"Arial",sans-serif">Felix</span> <br>
<br>
<br>
<br>
<span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#5F5F5F">From: </span><span style="font-size:9.0pt;font-family:"Arial",sans-serif">"Torgerson, J. Leigh\(US 332C\) via SIS-DTN" <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>></span>
<br>
<span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#5F5F5F">To: </span><span style="font-size:9.0pt;font-family:"Arial",sans-serif">"Shames, Peter M (US 312B)" <<a href="mailto:peter.m.shames@jpl.nasa.gov">peter.m.shames@jpl.nasa.gov</a>>,
"Vint Cerf" <<a href="mailto:vint@google.com">vint@google.com</a>>, "Dr. Keith L Scott" <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>></span>
<br>
<span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#5F5F5F">Cc: </span><span style="font-size:9.0pt;font-family:"Arial",sans-serif">"<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>" <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>>,
"Gifford, Kevin" <<a href="mailto:kevin.gifford@colorado.edu">kevin.gifford@colorado.edu</a>></span>
<br>
<span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#5F5F5F">Date: </span><span style="font-size:9.0pt;font-family:"Arial",sans-serif">12/10/2021 23:34</span>
<br>
<span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#5F5F5F">Subject: </span><span style="font-size:9.0pt;font-family:"Arial",sans-serif">Re: [Sis-dtn] [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2</span>
<br>
<span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#5F5F5F">Sent by: </span><span style="font-size:9.0pt;font-family:"Arial",sans-serif">"SIS-DTN" <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a>></span>
<o:p></o:p></p>
<div class="MsoNormal" align="center" style="text-align:center">
<hr size="1" width="100%" noshade="" style="color:#A0A0A0" align="center">
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<p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Fair enough – I’m not too worried about BPv6 one way or another – users are not limited to several dozen ISS payloads, a few cubesats that are due to launch next year, and KPLO. Everyone now is working on using BPv7,
and there aren’t going to be any pink sheets to the BPv6 book that I foresee.. <o:p>
</o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">I do believe LTPv1 and LTPv2 should be two separate books, unless CCSDS thinks it is OK to deprecate protocols that are in active use by missions and in continued support by the DSN. LTPv1 is a different protocol
from LTPv2; it isn’t merely an older version of the same protocol. Not backwards compatible, not just an enhanced version, but a new beast. Therefore we need a new book that can co-exist with LTPv1 until such time as no one is using LTPv1. Once LTPv2 is practically
ready for use in actual missions, we can debate when (or whether) to silverize LTPv1’s book.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Leigh<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b><span style="font-size:12.0pt">From:
</span></b><span style="font-size:12.0pt">"Shames, Peter M (US 312B)" <<a href="mailto:peter.m.shames@jpl.nasa.gov">peter.m.shames@jpl.nasa.gov</a>><b><br>
Date: </b>Tuesday, October 12, 2021 at 2:03 PM<b><br>
To: </b>"Torgerson, Jordan L (332M)" <<a href="mailto:jordan.l.torgerson@jpl.nasa.gov">jordan.l.torgerson@jpl.nasa.gov</a>>, Vint Cerf <<a href="mailto:vint@google.com">vint@google.com</a>>, "Scott, Keith L." <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>><b><br>
Cc: </b>"<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>" <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>>, "Gifford, Kevin" <<a href="mailto:kevin.gifford@colorado.edu">kevin.gifford@colorado.edu</a>><b><br>
Subject: </b>Re: [Sis-dtn] [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Hey Leigh,<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">I never said “make BPv6 (or LTPv1) Silver before the new BB exist”. Never did. Never would.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">I did say that I thought that <b><i>once</i></b> the new versions are published that then the old books should be “silverized”. This is the way that CCSDS handles such matters. Either that or we name them as two
separate protocols with two separate numbers. That does not remove them, they are still available. It does deprecate them. This is a consequence of both of these protocol version updates being designed to not be backward compatible.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">We (CCSDS, IETF, and the DTN community) have made all of our lives more complicated by pushing these specs while they were still maturing. We all want DTN to succeed, but making significant protocol changes this
early in the game is the cause of the problem and, as you have clearly pointed out, this is going to push complexity into deployments for some time into the future.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">That’s the reality. Now let’s deal with it as best we can until we can get to some more stable point.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Peter<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b><span style="font-size:12.0pt">From:
</span></b><span style="font-size:12.0pt">Leigh Torgerson <<a href="mailto:jordan.l.torgerson@jpl.nasa.gov">jordan.l.torgerson@jpl.nasa.gov</a>><b><br>
Date: </b>Tuesday, October 12, 2021 at 10:51 AM<b><br>
To: </b>Peter Shames <<a href="mailto:peter.m.shames@jpl.nasa.gov">peter.m.shames@jpl.nasa.gov</a>>, Vint Cerf <<a href="mailto:vint@google.com">vint@google.com</a>>, Keith Scott <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>><b><br>
Cc: </b>"<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>" <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>>, "Gifford, Kevin" <<a href="mailto:kevin.gifford@colorado.edu">kevin.gifford@colorado.edu</a>><b><br>
Subject: </b>Re: [Sis-dtn] [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">As I have mentioned before, I don’t have a problem with making the BPv6 book a “silver book” - other than existing missions that use it, no new missions are contemplating bpv6 now, and no new features will be added
to ION v3.7.x versions (bpv6), just bug fixes as they come up.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">However, I strongly disagree with making the ltpv1 spec “silver” at this time.
<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">There are currently bpv7 (ION 4.1) / ltpv1 systems being developed for flight missions, and assuming that the promised IETF spec for bpv7 is out soon (something we’ve been promised for months now), contracts may have
to be let soon by NASA that specify BPv7/LTPv1.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">What CCSDS never considers is the fact that from the time a new CCSDS spec hits the street until the DSN is funded to implement, test and be ready to offer that new protocol as a service, it’s $millions and years
before that happens.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">CCSDS and the DTN program already shot DTN in the kneecaps by rushing in to BPv7 right at the time NASA was starting to let contracts for vendors and get the DSN to support DTN – no specs for BPv7 meant no way to
specify DTN but to lamely describe “features” like “store and forward”, so vendors were left to either reinvent DTN by some software over UDP/IP/CCSDS telemetry or to look at cFS or ION with bpv6/ltpv1. CCSDS couldn’t even agree that a spec for BSSP was necessary,
so when we had to support that for the KPLO mission, we couldn’t even put it in the ICD properly (citing “man pages” isn’t an approved way to write an ICD).. So as of today, contracts that would come out in the next year or so for specifying DTN use in the
2024-25 timeframe (and near-term RFIs for Marsnet) will have to specify BPv7 (assuming IETF comes through soon) and LTPv1.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Then NASA will have to fund the DSN to incorporate ION v4.x.x to have a BPv7 and LTPv1 capability.
<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Nip ltpv1 in the bud? Here’s what it is going to take to get ltpv2 in place and ready to support missions that are supported by the DSN:<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">The steps:<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">1. </span>Define the spec and at least get a Redbook out –<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">2. </span>Pay at least two independent groups to write two LTPv2 implementations for the purpose of interoperability testing to validate the spec.
(standard CCSDS practice except when no one else cares, as was the case with SCPS)<o:p></o:p></p>
<ul type="disc">
<li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l1 level1 lfo3">
<span style="color:#4181C0">One implementation should be ION, as that is what will go into the DSN – and that’s not funded at present.</span><o:p></o:p></li></ul>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">3. </span>Test these reference implementation to certify that the new specification is correct, and then commence the process of going from Redbook to Bluebook.
<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">4. </span>Make these “reference implementations” available to DTN implementors and the DTN ION Hardening / DSN implementation test teams at JPL
to <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">a. </span>Write the official ION implementation of LTPv2 for the DSN<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">b. </span>Validate the performance, memory management, set-up methods and efficiency of the new LTPv2, at least for DSN RF downlink speeds. (Optical
comm implementations at Table Mountain, etc is a whole ‘nother discussion)<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">5. </span>Fund the DSN, NSN, and maybe MSU, to install, test and operate LTPv2 so the ground infrastructure can support it.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">6. </span>Then we will be in a position to encourage use of LTPv2, assist any early-stage vendors to switch over to LTPv2, and come up with cost-benefits
analyses that will show NASA why it is worth paying vendors or (by then) flight missions to switch over to LTPv2, do all the interoperability testing with NSN and DSN, etc.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">If CCSDS and SCaN can come up with the budget and timetable that would let steps 1-6 be accomplished in the next 12-24 months, then maybe killing ltpv1 now would be OK. But I also might as well ask for a pony for
Christmas. <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">On the other hand, if you just want to insure that DTN will not be used in Lunanet until 2030, then go ahead and deprecate ltpv1 now, making it unlikely any vendor in the next 3-4 years will implement ltp at all (no
spec, no DSN support, no sale. I know you can still cite a silver book in a contract, but knowing that ltpv1 is a deprecated standard means no one would be eager to implement it.)<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">The DSN is going to have to support 3 versions of DTN as it stands now – BPv6/ltpv1, BPv7/ltpv1 and BPv7/ltp2, and two of the three are not funded for infusion any time soon. (and ION development isn’t funded yet
for ltpv2 compatibility.) No one has funded the implementation of USLP in the DSN yet either, by the way, and no reference implementations have been made available to commercial telemetry vendors.. I hold that up as yet another case where CCSDS specs come
out years and years before anyone in the community is ready to use them in an end-to-end system.. (Want to discuss how long it took between the time I was NASA rapporteur for “protocol-X” (circa 1997?), which became CFDP, and the time when some missions actually
used it?) <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">I have no faith that steps 1-6 above can be completed in time to get the Lunar missions on the bandwagon to use BPv7 over a “high speed” LTP version not many spacecraft would even need. (I believe that LTPv2 could
well serve for specialized optical comm missions that needed the high speed FPGA implementations, and LTPv1 could continue to serve most RF missions.)<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">We can move in the direction of BPv7/LTPv2 certainly, but don’t eliminate the CCSDS Bluebook for LTPv1 until there are specs for BPv7 and LTPv2 that can be used by NASA in contracts (or by DSN in ICDs).<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Leigh<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b><span style="font-size:12.0pt;font-family:"Times New Roman",serif">J. Leigh Torgerson</span></b><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Space Communications Networking Architect</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Protocol Technology Lab Manager
</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Communications Architectures & Research (332)</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Jet Propulsion Laboratory</span></b><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b><span style="font-size:12.0pt;font-family:"Times New Roman",serif">4800 Oak Grove Drive M/S: 238-420</span></b><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Pasadena, CA 91109</span></b><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Office: (818) 393-0695</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Email:
</span><a href="mailto:ltorgerson@jpl.nasa.gov"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:#0082BF">ltorgerson@jpl.nasa.gov</span></a><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"> </span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b><span style="font-size:12.0pt">From:
</span></b><span style="font-size:12.0pt">SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a>> on behalf of "Shames, Peter M (US 312B) via SIS-DTN" <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>><b><br>
Reply-To: </b>"Shames, Peter M (US 312B)" <<a href="mailto:peter.m.shames@jpl.nasa.gov">peter.m.shames@jpl.nasa.gov</a>><b><br>
Date: </b>Monday, October 11, 2021 at 5:55 PM<b><br>
To: </b>Vint Cerf <<a href="mailto:vint@google.com">vint@google.com</a>>, "Scott, Keith L." <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>><b><br>
Cc: </b>"<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>" <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>>, "Gifford, Kevin" <<a href="mailto:kevin.gifford@colorado.edu">kevin.gifford@colorado.edu</a>><b><br>
Subject: </b>Re: [Sis-dtn] [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Vint and Keith,<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Given that we are really just getting started with building and deploying DTN and LTP based systems in space in any broad sense I think we are better off silverizing these now and nipping in the bud any expansion
of these older protocols we are trying to leave behind.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">With IPv4 vs IPv6 there was already a major deployment of IPv4 such that it could not easily be abandoned. In our case I think LTPv1 and BPv6 are more like IPv1, v2, and v3. They must have existed along the way
to IPv4, but they are now lost to the dusts of time. In the RFC Editor files there is not even a mention of these, but I assume that they existed at some point.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">I worry with our current relatively small community that we will just start to build in more complexity if we perpetuate both versions of both of these key protocols. <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Regards, Peter<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b><span style="font-size:12.0pt">From:
</span></b><span style="font-size:12.0pt">Vint Cerf <<a href="mailto:vint@google.com">vint@google.com</a>><b><br>
Date: </b>Monday, October 11, 2021 at 7:18 AM<b><br>
To: </b>Keith Scott <<a href="mailto:KSCOTT@mitre.org">KSCOTT@mitre.org</a>><b><br>
Cc: </b>"<a href="mailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de</a>" <<a href="mailto:tomaso.decola@dlr.de">tomaso.decola@dlr.de</a>>, Peter Shames <<a href="mailto:peter.m.shames@jpl.nasa.gov">peter.m.shames@jpl.nasa.gov</a>>, "<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>"
<<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>>, "Gifford, Kevin" <<a href="mailto:Kevin.Gifford@colorado.edu">Kevin.Gifford@colorado.edu</a>><b><br>
Subject: </b>Re: [Sis-dtn] [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">i think Keith and Leigh have correctly characterized the situation. I would stick with both as valid but incompatible. CF: IPv4 and IPv6'
<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">v<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">On Mon, Oct 11, 2021 at 10:12 AM Dr. Keith L Scott <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>> wrote:<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Peter,<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">I think the real issue at hand is whether or not to maintain the LTPv1 spec as Blue once LTPv2 is published. <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">My interpretation of Leigh’s argument is that vendors are currently implementing to LTPv1 (and the current BPv6-based BP for CCSDS Book) and that deprecating those specs in favor of new, non-backward-compatible ones
would be looked upon unfavorably.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> v/r,<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> --keith<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:180.0pt;margin-left:0cm">
<b><span style="font-size:12.0pt">From: </span></b><a href="mailto:Tomaso.deCola@dlr.de" target="_blank"><span style="font-size:12.0pt">Tomaso.deCola@dlr.de</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:Tomaso.deCola@dlr.de" target="_blank"><span style="font-size:12.0pt">Tomaso.deCola@dlr.de</span></a><span style="font-size:12.0pt">><b><br>
Date: </b>Monday, October 11, 2021 at 3:11 AM<b><br>
To: </b></span><a href="mailto:peter.m.shames@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">peter.m.shames@jpl.nasa.gov</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:peter.m.shames@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">peter.m.shames@jpl.nasa.gov</span></a><span style="font-size:12.0pt">><b><br>
Cc: </b>Dr. Keith L Scott <</span><a href="mailto:kscott@mitre.org" target="_blank"><span style="font-size:12.0pt">kscott@mitre.org</span></a><span style="font-size:12.0pt">>, Gifford, Kevin <</span><a href="mailto:kevin.gifford@colorado.edu" target="_blank"><span style="font-size:12.0pt">kevin.gifford@colorado.edu</span></a><span style="font-size:12.0pt">>,
</span><a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">marc.sanchez.net@jpl.nasa.gov</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">marc.sanchez.net@jpl.nasa.gov</span></a><span style="font-size:12.0pt">>,
</span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank"><span style="font-size:12.0pt">sis-dtn@mailman.ccsds.org</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank"><span style="font-size:12.0pt">sis-dtn@mailman.ccsds.org</span></a><span style="font-size:12.0pt">><b><br>
Subject: </b>RE: [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Dear Peter,<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Thank you for your kind support and availability for helping us in finding a suitable solution.
<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Indeed the two options you have mentioned are also those we have put on the table as possible solutions, although both of them show pros and cons and therefore compromise and agreement/consensus between the parties
will have to be reached. This discussion will keep on going during the next DTN telco as well as the official CCSDS DTN WG Fall meetings in order to reach soon an agreed approach as also mentioned by Keith in a previous e-mail. In case no solution will be
agreed, then I’ll certainly bring this point in the SIS area summary at the CESG meeting in November in order to find a way out for this impasse. Obviously, I’ll certainly count on your and other CESG colleagues suggestions to move forward and more importantly
to avoid any postponed decision that would be detrimental to the activities of the DTN WG.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Best Regards<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Tomaso<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b>From:</b> Shames, Peter M (US 312B) <<a href="mailto:peter.m.shames@jpl.nasa.gov" target="_blank">peter.m.shames@jpl.nasa.gov</a>>
<b><br>
Sent:</b> Samstag, 9. Oktober 2021 01:26<b><br>
To:</b> Kevin K Gifford <<a href="mailto:kevin.gifford@colorado.edu" target="_blank">kevin.gifford@colorado.edu</a>>; Dr. Keith L Scott <<a href="mailto:kscott@mitre.org" target="_blank">kscott@mitre.org</a>>; Cola, Tomaso de <<a href="mailto:Tomaso.deCola@dlr.de" target="_blank">Tomaso.deCola@dlr.de</a>>;
Sanchez Net, Marc (US 332H) <<a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank">marc.sanchez.net@jpl.nasa.gov</a>><b><br>
Cc:</b> <a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a><b><br>
Subject:</b> Re: [EXTERNAL] Re: [EXT] RE: LTP vs LTPv2<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Guys,<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">As a long term member of the CESG I do agree that you can kick it “upstairs” to the CESG and have, I believe, a hope of getting a sensible response (most of the time). Heck, we are human and therefore fallible.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">From my own point of view I recommend doing two things:<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p><span style="font-size:10.0pt;font-family:"Arial",sans-serif">1. </span>As I understand it, they are different protocols, hence not “backward compatible”. Using the “version” option, including, in this case, adopting some explicit name extension
like LTPv2 makes the most sense to me. The rationale for that is that what you plan to produce is not backward compatible with v1. In other words, there is no way to configure V2, without the new options, and still have a v1 implementation accept it. <o:p></o:p></p>
<p style="margin-top:0cm;?á¯
??Ï???As
I understand it, they are different protocols, hence not “backward compatible”.
Using the “version” option, including, in this case, adopting some
e</span>">
<span style="font-size:10.0pt;font-family:"Arial",sans-serif">2. </span>Silverize the v1 book. This is normally done when a new protocol version is created. The old silver book will still be available and it may be referenced with its (new) silver
name and number. This has happened before with other specs. It is not unusual for some mission to nail their interface to some specific version of a document, even, in some cases, a Red Book (which is really dangerous since they are likely to change). <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">If you want to discuss this further please let me know. And it you do decide to send it to the CESG you now know where I stand, and why. Of course, if any of my assumptions are flawed I am happy to be corrected.<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt">Cheers, Peter<o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><b><span style="font-size:12.0pt">From:
</span></b><span style="font-size:12.0pt">Kevin K Gifford <</span><a href="mailto:kevin.gifford@colorado.edu" target="_blank"><span style="font-size:12.0pt">kevin.gifford@colorado.edu</span></a><span style="font-size:12.0pt">><b><br>
Date: </b>Friday, October 8, 2021 at 11:58 AM<b><br>
To: </b>Keith Scott <</span><a href="mailto:kscott@mitre.org" target="_blank"><span style="font-size:12.0pt">kscott@mitre.org</span></a><span style="font-size:12.0pt">>, "</span><a href="mailto:Tomaso.deCola@dlr.de" target="_blank"><span style="font-size:12.0pt">Tomaso.deCola@dlr.de</span></a><span style="font-size:12.0pt">"
<</span><a href="mailto:Tomaso.deCola@dlr.de" target="_blank"><span style="font-size:12.0pt">Tomaso.deCola@dlr.de</span></a><span style="font-size:12.0pt">>, Marc Sanchez Net <</span><a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">marc.sanchez.net@jpl.nasa.gov</span></a><span style="font-size:12.0pt">><b><br>
Cc: </b>"</span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank"><span style="font-size:12.0pt">sis-dtn@mailman.ccsds.org</span></a><span style="font-size:12.0pt">" <</span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank"><span style="font-size:12.0pt">sis-dtn@mailman.ccsds.org</span></a><span style="font-size:12.0pt">>,
Peter Shames <</span><a href="mailto:peter.m.shames@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">peter.m.shames@jpl.nasa.gov</span></a><span style="font-size:12.0pt">>, Kevin K Gifford <</span><a href="mailto:kevin.gifford@colorado.edu" target="_blank"><span style="font-size:12.0pt">kevin.gifford@colorado.edu</span></a><span style="font-size:12.0pt">><b><br>
Subject: </b>[EXTERNAL] Re: [EXT] RE: LTP vs LTPv2</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt">Hi SIS-DTN -
</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt">FWIW, I want to emphasize that the CESG does a great job in this regard (fixing issues that arise in WGs or inter-WG conflicts or inter-agency conflicts).</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt">-- Keith was a member of the CESG for several years and understands this vital role that the CESG plays in issues such as this</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt">Thus, my
<b>two cents worth</b> is await CESG advice as well as Keith already stated (I wanted to maybe ease any queasiness in regard to CESG involvement/inputs).</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt">Thanks.</span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:12.0pt">Kevin</span><o:p></o:p></p>
<div class="MsoNormal" align="center" style="text-align:center">
<hr size="1" width="100%" align="center">
</div>
<p style="margin:0cm;margin-bottom:.0001pt"><b>From:</b> SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org" target="_blank">sis-dtn-bounces@mailman.ccsds.org</a>> on behalf of Dr. Keith L Scott <<a href="mailto:kscott@mitre.org" target="_blank">kscott@mitre.org</a>><b><br>
Sent:</b> Friday, October 8, 2021 12:49 PM<b><br>
To:</b> <a href="mailto:Tomaso.deCola@dlr.de" target="_blank">Tomaso.deCola@dlr.de</a> <<a href="mailto:Tomaso.deCola@dlr.de" target="_blank">Tomaso.deCola@dlr.de</a>>;
<a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank">marc.sanchez.net@jpl.nasa.gov</a> <<a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank">marc.sanchez.net@jpl.nasa.gov</a>><b><br>
Cc:</b> <a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a> <<a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a>><b><br>
Subject:</b> Re: [Sis-dtn] [EXT] RE: LTP vs LTPv2 <o:p></o:p></p>
<p style="margin:0cm;margin-bottom:.0001pt"> <o:p></o:p></p>
<p class="MsoNormal"><br>
OK fine, if the CESG decides to not rule on it, great, we’ll make a decision in the WG and they can live with it (and we can certainly discuss it SOME in the WG; don’t want to put too much time into it until the CESG is at least given a chance to get us out
of this). <br>
<br>
--keith <br>
<o:p></o:p></p>
<p><b><span style="font-size:12.0pt">From: </span></b><a href="mailto:Tomaso.deCola@dlr.de" target="_blank"><span style="font-size:12.0pt">Tomaso.deCola@dlr.de</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:Tomaso.deCola@dlr.de" target="_blank"><span style="font-size:12.0pt">Tomaso.deCola@dlr.de</span></a><span style="font-size:12.0pt">><b><br>
Date: </b>Friday, October 8, 2021 at 10:04 AM<b><br>
To: </b>Dr. Keith L Scott <</span><a href="mailto:kscott@mitre.org" target="_blank"><span style="font-size:12.0pt">kscott@mitre.org</span></a><span style="font-size:12.0pt">>,
</span><a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">marc.sanchez.net@jpl.nasa.gov</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">marc.sanchez.net@jpl.nasa.gov</span></a><span style="font-size:12.0pt">><b><br>
Cc: </b></span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank"><span style="font-size:12.0pt">sis-dtn@mailman.ccsds.org</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank"><span style="font-size:12.0pt">sis-dtn@mailman.ccsds.org</span></a><span style="font-size:12.0pt">><b><br>
Subject: </b>RE: [EXT] RE: LTP vs LTPv2</span><o:p></o:p></p>
<p class="MsoNormal"><br>
Hi Keith, <br>
<br>
I agree with your point on troubles in maintaining two books and the fact that this will imply the same treatment for BPv7. Then whether agencies are happy to refer to a silver book rather than a blue book is a bit question mark in my opinion. I remember we
decided a few years ago not to silverize SCPS-TP exactly because there were activities or usage of the corresponding blue book.
<br>
We can certainly bring this matter to the next CESG meeting, although I fear that there might be no strict decision in this regard, since I think there is no specific rule again either approaches and the hot potato could be sent back to WG.
<br>
<br>
Regards, <br>
<br>
Tomaso <br>
<b>From:</b> Dr. Keith L Scott <<a href="mailto:kscott@mitre.org" target="_blank">kscott@mitre.org</a>>
<b><br>
Sent:</b> Freitag, 8. Oktober 2021 15:52<b><br>
To:</b> Cola, Tomaso de <<a href="mailto:Tomaso.deCola@dlr.de" target="_blank">Tomaso.deCola@dlr.de</a>>;
<a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank">marc.sanchez.net@jpl.nasa.gov</a><b><br>
Cc:</b> <a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a><b><br>
Subject:</b> Re: [EXT] RE: LTP vs LTPv2 <br>
<br>
I don’t like it, but I propose that the WG move forward with developing the book and you bring up the new-version vs. new-book issue to the CESG.
<br>
<br>
Reasons I don’t like the two-book solution: <br>
<o:p></o:p></p>
<ul type="disc">
<li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l3 level1 lfo6">
So now we’re maintaining two versions of LTP, which version are folks supposed to choose for missions going forward? They’ll choose the one with flight heritage, right?
<o:p></o:p></li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l3 level1 lfo6">
We’ll have to do the same thing with BPv7 <o:p></o:p></li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l3 level1 lfo6">
There’s a version number in the header; receivers will know what was sent. <o:p></o:p></li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l3 level1 lfo6">
The book as Silver is still reference-able. If folks have systems they’re building to the current (v1) book, they can switch to referencing the silver book.
<o:p></o:p></li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l3 level1 lfo6">
Why don’t we do that with ALL CCSDS books, backward-compatible or not?<o:p></o:p></li></ul>
<p class="MsoNormal"> <br>
--keith <br>
<br>
<o:p></o:p></p>
<p><b><span style="font-size:12.0pt">From: </span></b><a href="mailto:Tomaso.deCola@dlr.de" target="_blank"><span style="font-size:12.0pt">Tomaso.deCola@dlr.de</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:Tomaso.deCola@dlr.de" target="_blank"><span style="font-size:12.0pt">Tomaso.deCola@dlr.de</span></a><span style="font-size:12.0pt">><b><br>
Date: </b>Friday, October 8, 2021 at 4:19 AM<b><br>
To: </b></span><a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">marc.sanchez.net@jpl.nasa.gov</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank"><span style="font-size:12.0pt">marc.sanchez.net@jpl.nasa.gov</span></a><span style="font-size:12.0pt">>,
Dr. Keith L Scott <</span><a href="mailto:kscott@mitre.org" target="_blank"><span style="font-size:12.0pt">kscott@mitre.org</span></a><span style="font-size:12.0pt">><b><br>
Cc: </b></span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank"><span style="font-size:12.0pt">sis-dtn@mailman.ccsds.org</span></a><span style="font-size:12.0pt"> <</span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank"><span style="font-size:12.0pt">sis-dtn@mailman.ccsds.org</span></a><span style="font-size:12.0pt">><b><br>
Subject: </b>[EXT] RE: LTP vs LTPv2</span><o:p></o:p></p>
<p class="MsoNormal"><br>
Then probably we should better keep two books, one with the “old LTP” for which we’ll do some pink sheets to fix some inconsistencies and another one (the new LTP). In such a away we could have two versions of LTP available, similarly to IPv4 and IPv6 in IETF.
Probably we may have to slightly change the title of the books (v1 and v2?) to have a clear demarcation between the two version of the protocols and avoid any ambiguity.
<br>
<a href="mailto:kscott@mitre.org" target="_blank">@Scott, Keith L.</a>:what do you think?
<br>
<br>
Tomaso <br>
<br>
<b>From:</b> SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org" target="_blank">sis-dtn-bounces@mailman.ccsds.org</a>>
<b>On Behalf Of </b>Sanchez Net, Marc (US 332H) via SIS-DTN<b><br>
Sent:</b> Donnerstag, 7. Oktober 2021 00:21<b><br>
To:</b> <a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a><b><br>
Subject:</b> [Sis-dtn] LTP vs LTPv2 <br>
<br>
All, <br>
<br>
I had to leave today’s meeting early. Did we reach consensus on how to proceed? <br>
<br>
Also, I will note that some colleagues at JPL (I have similar concerns) do not really like the idea of turning the current version of LTP into a silver book. The problem is that, by definition, a silver book implies that a protocol is deprecated or obsolete,
but several systems that are being built today use BPv6+LTP or BPv7+LTP and thus might be in operation for a long time. So, essentially, we are “telling” industry that they have developed an already obsolete standard?
<br>
<br>
Best, <br>
-----------------------------------------------------------------------------------------------------------------------
<br>
Marc Sanchez Net <br>
<span style="font-size:10.0pt;color:gray">Telecommunications Engineer</span> <br>
<span style="font-size:10.0pt;color:gray">Jet Propulsion Laboratory</span> <br>
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</span><a href="mailto:marc.sanchez.net@jpl.nasa.gov" target="_blank"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">marc.sanchez.net@jpl.nasa.gov</span></a>
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