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<p class="MsoNormal">Dear SLP WG,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">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></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">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></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Here are my thoughts below:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Pro:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">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></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Con:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">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></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">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></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">Greg – Chairman CCSDS SLP WG<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:none">Greg Kazz<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:none">Principal Engineer<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:none">Technical Group Supervisor,<o:p></o:p></span></p>
<p class="MsoNormal"><span 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 style="font-size:11.0pt;mso-ligatures:none">Jet Propulsion Laboratory<o:p></o:p></span></p>
<p class="MsoNormal"><span 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 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 style="font-size:11.0pt;mso-ligatures:none"><o:p></o:p></span></p>
<p class="MsoNormal"><span 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 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: greg.j.kazz@jpl.nasa.gov
</span><span style="font-size:11.0pt;mso-ligatures:none"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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