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Dear SLP members,</div>
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I have received the following action item from the CCSDS today:</div>
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<div><font size="1" color="#5f5f5f" face="sans-serif" style="color: rgb(0, 0, 0); font-family: Calibri, sans-serif; font-size: 20px;">Date: </font><font size="1" face="sans-serif" style="color: rgb(0, 0, 0); font-family: Calibri, sans-serif; font-size: 20px;">24/11/2014
20:23</font><span style="color: rgb(0, 0, 0); font-family: Calibri; font-size: medium;"> </span><br style="font-family: Calibri; font-size: medium;">
<font size="1" color="#5f5f5f" face="sans-serif" style="color: rgb(0, 0, 0); font-family: Calibri, sans-serif; font-size: 20px;">Subject: </font><font size="1" face="sans-serif" style="color: rgb(0, 0, 0); font-family: Calibri, sans-serif; font-size: 20px;">SLP-WG
Action Item from London</font><span style="color: rgb(0, 0, 0); font-family: Calibri; font-size: medium;"> </span><br style="font-family: Calibri; font-size: medium;">
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<font size="2" face="Calibri" style="color: rgb(0, 0, 0); font-family: Calibri; font-size: 20px;">Below is the action item assigned to the SLP WG. Let me know if you want to send to Greg or if you want me to send to Greg directly.</font><span style="color: rgb(0, 0, 0); font-family: Calibri; font-size: medium;"> </span><br style="font-family: Calibri; font-size: medium;">
<font size="2" face="Calibri" style="color: rgb(0, 0, 0); font-family: Calibri; font-size: 20px;"> </font><span style="font-family: Calibri; font-size: medium;"></span>
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<font size="2" face="Times New Roman">CMC-A-2014-11-19</font></td>
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<font size="2" face="Times New Roman">The SLP WG is requested to do an analysis and create procedures (if applicable) for assigning SCIDs to multiple spacecraft (this is needed for V1 and V2 but most critical for V2). Provide recommendations to the Secretariat
for forwarding to the CMC and SANA Steering Group.</font> <br>
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<font size="2" face="Times New Roman">Action: SLP WG</font> <br>
<font size="2" face="Times New Roman">Due Date: 31 December 2014</font> <br>
<font size="2" face="Times New Roman">Status: Open</font></td>
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<p style="color: rgb(0, 0, 0); font-family: Calibri; font-size: medium;">Obviously, we cannot nor do we need to meet the 31 Dec 2014 deadline. It is negotiable with the CMC.</p>
<p style="color: rgb(0, 0, 0); font-family: Calibri; font-size: medium;">However, I want to bring this A.I. to your attention and explain it’s motivation.</p>
<p style="color: rgb(0, 0, 0); font-family: Calibri; font-size: medium;">The main reason for this A.I. was a warning provided by SANA to the CMC after the London meeting that Version 2 SCIDs (AOS) may very well be exhausted within 6 months time. The number
of "available “ V2 SCIDs is approx. 13%. The number of V1 SCIDs “available” meaning capable of being assigned is approx 27%. So the motivation is clear. </p>
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<p style="color: rgb(0, 0, 0); font-family: Calibri; font-size: medium;">What needs to be done? CMC wants a recommendation from us on the way forward. Apparently the wording in the A.I. referring to "<span class="Apple-style-span" style="border-collapse: collapse; border-spacing: 2px;">assigning
SCIDs to multiple spacecraft " had two origins:</span></p>
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<li><span class="Apple-style-span" style="border-collapse: collapse; border-spacing: 2px;">Requests that are submitted for the same SCID for both type V1 and V2 SCIDs.</span></li><li><span class="Apple-style-span" style="border-collapse: collapse; border-spacing: 2px;">Requests that are submitted to assign SCIDs for more than one spacecraft (as in a constellation)</span></li></ol>
<p style="color: rgb(0, 0, 0); font-family: Calibri; font-size: medium;"><font size="2" face="Calibri"> </font></p>
<p style="color: rgb(0, 0, 0); font-family: Calibri; font-size: medium;"><font size="2" face="Calibri">So SLP WG needs to consider solutions to the problem of CCSDS running out of assignable SCIDs. Some immediate thoughts come to mind in how to increase the
SCID assignment pool:</font></p>
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<li><font size="2" face="Calibri"><font size="3">Short term: Have each agency poll it</font>’<font size="3">s missions to return SCID assignments no longer in use.</font></font></li><li><font face="Calibri"><font size="2"><font size="3">Longer term: Adopt USLP which increases the size of the SCID to at least 13 bits and does away with multiple SCID assignments due to use (Telemetry, Telecommand, Proximity).</font></font></font></li></ul>
<div>I look forward to continuing this dialog with you after the holiday.</div>
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<div>Happy holidays to all !</div>
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<div>Greg </div>
<div>Chairman CCSDS SLS-SLP WG</div>
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