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<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Hi Greg,
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">I haven’t spoken with Moonlight people yet and I had not attended the meeting mentioned by Ignacio held a couple of days ago as I was not involved, therefore I’m only speculating
here. I will coordinate internally with Moonlight and Ignacio to get a better picture.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">In any case, I still don’t get what kind of problem Moonlight project is trying to solve by using AOS over Prox-1.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">At a first glance it seems that they will get into more troubles than those they want to fix, but, again, pending listening to Moonlight opinions.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">In fact, AOS is fixed length frames and does not support COP.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">In the end, it might work with workarounds, however I would not recommend it.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Preferred options:<o:p></o:p></span></p>
<ol style="margin-top:0cm" start="1" type="1">
<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Use prox-1 frames OR<o:p></o:p></span></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Use USLP
<o:p></o:p></span></li></ol>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Cheers<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Marco
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none">From:</span></b><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none"> SLS-SLP <sls-slp-bounces@mailman.ccsds.org>
<b>On Behalf Of </b>Kazz, Greg (US 312B) via SLS-SLP<br>
<b>Sent:</b> 22 May 2023 19:42<br>
<b>To:</b> Kazz, Greg (US 312B) via SLS-SLP <sls-slp@mailman.ccsds.org><br>
<b>Subject:</b> [Sls-slp] A Mission Proposal - AOS Transfer Frames over Proximity-1 Session Control<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">Dear SLP WG,<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">A question has come to me via the ESA Moonlight mission regarding the feasibility of using the AOS Space Data Link Protocol over the Proximity-1 session control (state tables that control link establishment, data exchange,
and link termination). <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">I would like to know your opinion on this question:
<span style="background:yellow;mso-highlight:yellow">What does the SLP WG think about the possibility of using the AOS transfer frame format with Prox-1 session control ?</span><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">Here are my thoughts below:<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">Pro:<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">As you may know from our last meeting, the WG is attempting to split the Prox-1 SDLP book into a separate session control book, separate COP-P book, and a separate transfer frame PDU book, that one similar to the existing
TC, TM, AOS books. If we succeed in that endeavor, it would be much easier for a mission to swap in different CCSDS data link layer protocols below the Prox-1 session control sublayer.
<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">Con:<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">However, all the fine details to ensure dividing up the Prox-1 books has not yet been worked out by the SLP WG. This really has only been done for USLP and Prox-1. Nor has any interoperability testing been accomplished
as well to clearly demonstrate interoperability. Therefore, it would be the responsibility of each and every mission to take on that additional risk, if they were to use AOS for example with Prox-1 session control. Lastly, CCSDS created USLP in order to do
just that – replace AOS, TM, TC, Prox-1 with one link layer PDU useable in all venues. USLP has been interoperability tested by CCSDS.
<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">We have a <span style="background:yellow;mso-highlight:yellow">
short fuse of two weeks</span> to gather our inputs to this question, so I appreciate a quick response back from you all.<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">Best regards,<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">Greg – Chairman CCSDS SLP WG<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" style="font-size:11.0pt;mso-ligatures:none">Greg Kazz<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none">Principal Engineer<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none">Technical Group Supervisor,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none">312B Project Protection, Project Software, and End to End Information System Engineering<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none">Jet Propulsion Laboratory<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none">4800 Oak Grove Dr., M/S 301-490<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="ES-MX" style="font-size:11.0pt;mso-ligatures:none">Pasadena, CA 91109</span><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="ES-MX" style="font-size:11.0pt;mso-ligatures:none">1+(818)393 6529(voice)</span><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none">1</span><span lang="ES-MX" style="font-size:11.0pt;mso-ligatures:none">+(818)393 6871(fax)</span><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="ES-MX" style="font-size:11.0pt;mso-ligatures:none">email:
<a href="mailto:greg.j.kazz@jpl.nasa.gov">greg.j.kazz@jpl.nasa.gov</a> </span><span lang="EN-US" style="font-size:11.0pt;mso-ligatures:none"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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