<span style=" font-size:11pt;font-family:Arial">Dear NAV and SM&C
leads,</span>
<br>
<br><span style=" font-size:11pt;font-family:Arial">I believe that your
WGs should be in sync with this endeavour. Please make sure to participate
at the next opportunity.</span>
<br>
<br><span style=" font-size:11pt;font-family:Arial">Regards,</span>
<br>
<br><span style=" font-size:11pt;font-family:Arial">__Mario</span>
<br><span style=" font-size:9pt;color:#800080;font-family:sans-serif">-----
Forwarded by Mario Merri/esoc/ESA on 23/10/2018 11:43 -----</span>
<br>
<br><span style=" font-size:9pt;color:#5f5f5f;font-family:sans-serif">From:
       </span><span style=" font-size:9pt;font-family:sans-serif">"Shames,
Peter M (312B)" <Peter.M.Shames@jpl.nasa.gov></span>
<br><span style=" font-size:9pt;color:#5f5f5f;font-family:sans-serif">To:
       </span><span style=" font-size:9pt;font-family:sans-serif">CCSDS
Engineering Steering Group - CESG All <cesg-all@mailman.ccsds.org></span>
<br><span style=" font-size:9pt;color:#5f5f5f;font-family:sans-serif">Date:
       </span><span style=" font-size:9pt;font-family:sans-serif">23/10/2018
11:40</span>
<br><span style=" font-size:9pt;color:#5f5f5f;font-family:sans-serif">Subject:
       </span><span style=" font-size:9pt;font-family:sans-serif">[Cesg-all]
FW: [Sea-time] Notes from CCSDS Systems Engineering Area (SEA) Time Birds
of a Feather (BoF) meeting, 17 Oct 18</span>
<br><span style=" font-size:9pt;color:#5f5f5f;font-family:sans-serif">Sent
by:        </span><span style=" font-size:9pt;font-family:sans-serif">"CESG-All"
<cesg-all-bounces@mailman.ccsds.org></span>
<br>
<hr noshade>
<br>
<br>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">Dear
CCSDS AD and WG chairs,</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">During
last week's working meetings we held a short meeting to explore restarting
the Time BoF.  Minutes from that are attached.  Please inform
members of your WGs, and your agencies, that this work is again being considered
as a new Working Group.   It should quickly become clear that this
effort will touch, in one way or another, every CCSDS area of work.</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">The
appended email will provide links to the data and the mailing list.  Feel
free to sign up or to pass the info on to any colleagues who may have an
interest.</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">Thanks,
Peter</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:12pt;font-family:Calibri"><b>From:
</b>SEA-TIME <sea-time-bounces@mailman.ccsds.org> on behalf of Peter
Shames <Peter.M.Shames@jpl.nasa.gov><b><br>
Date: </b>Tuesday, October 23, 2018 at 2:27 AM<b><br>
To: </b>"Sanchez, Erika A." <Erika.Sanchez@jhuapl.edu>,
"Birrane, Edward J." <Edward.Birrane@jhuapl.edu>, "Colin.Haddow@esa.int"
<Colin.Haddow@esa.int>, Jon Hamkins <Jon.Hamkins@jpl.nasa.gov>,
Victor Sank <victor.j.sank@nasa.gov>, Keith Scott <kscott@mitre.org>,
Holger Dreihahn/esoc/ESA <Holger.Dreihahn@esa.int>, "Pitts,
Robert L. (MSFC-HP27)[HOSC SERVICES CONTRACT]" <robert.l.pitts@nasa.gov>,
"osvaldo.peinado@dlr.de" <osvaldo.peinado@dlr.de><b><br>
Cc: </b>"sea-time@mailman.ccsds.org" <sea-time@mailman.ccsds.org><b><br>
Subject: </b>[Sea-time] Notes from CCSDS Systems Engineering Area (SEA)
Time Birds of a Feather (BoF) meeting, 17 Oct 18</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">Dear
Time BoF colleagues,</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">What
follows are my slightly edited notes from the SEA-Time BoF we held over
lunch on 17 Oct 18.  I am sending them to those who were present at
the meeting and also to the existing SEA-TIME mailing list.  If you
are not already on this email list please go to:</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><a href="https://mailman.ccsds.org/cgi-bin/mailman/listinfo/sea-time"><span style=" font-size:11pt;color:#0082bf;font-family:Calibri"><u>https://mailman.ccsds.org/cgi-bin/mailman/listinfo/sea-time</u></span></a></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">and
sign up.  This will give you access to any on-going discussions.  Keep
in mind that this any BoF is a "pre-Working Group".  Its
intended activities are to create a charter (plan of work) and a concept
paper (description of what will be standardized) for a proposed CCSDS Working
Group.  Once we have agreed on what we think should be done, created
these two (rather modest) documents, and have identified sufficient resources
to accomplish the work, we will petition to have the WG formalized.  Then
the <b><i>real</i></b> work will begin.  </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">We
would like to have a telecon to continue forward momentum.  Please
go to this Doodle Poll and indicate which of the proposed dates and times
work best for you.  Please pick more than one and indicate yes, no,
or "if need be".  Once we settle on a date I'll setup a
WebEx and send it to the mailing list.  Please sign up if you wish
to be a part of the on-going discussions.  Feel free to notify any
colleagues who might wish to contribute.</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><a href=https://doodle.com/poll/4vrex3wxv6cmbfdr><span style=" font-size:11pt;font-family:Calibri">https://doodle.com/poll/4vrex3wxv6cmbfdr</span></a></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">You
can find the old materials from the original Time BoF here:</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><a href="https://cwe.ccsds.org/sea/docs/Forms/AllItems.aspx?RootFolder=%2fsea%2fdocs%2fWork%20Completed%20%28Closed%20WGs%29%2fTime%20Code%20and%20Sync%20Birds%20of%20a%20Feather&FolderCTID=0x012000F83FD93BEFF45E4FB5D1769B01CA762F"><span style=" font-size:11pt;font-family:Calibri">https://cwe.ccsds.org/sea/docs/Forms/AllItems.aspx?RootFolder=%2fsea%2fdocs%2fWork%20Completed%20%28Closed%20WGs%29%2fTime%20Code%20and%20Sync%20Birds%20of%20a%20Feather&FolderCTID=0x012000F83FD93BEFF45E4FB5D1769B01CA762F</span></a></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">I
will ask the Secretariat to reinstate the SEA-Time as an active BoF.</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">Thanks
for the support, Peter</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"><b>Time
BoF - 17 Oct 18</b></span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri">Attendees:
Erika Sanchez, Ed Birrane, Colin Haddow, Jon Hamkins, Victor Sank, Keith
Scott, Holger Driehahn</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Symbol">·
        </span><span style=" font-size:11pt;font-family:Calibri">Three
basic topics to be addressed (time stamp, time exchange, time correlation)</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Symbol">·
        </span><span style=" font-size:11pt;font-family:Calibri">Discussion
about what is now being done.  Most missions do this now …</span><span style=" font-size:12pt;font-family:Calibri">
</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">time
representation (time code)</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">time
stamp (clock format)</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">time
exchange via SPP header (in some form) or mission specific</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">Earth
Receive Time (ERT) from ground station, typically via SLE</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">Mission
specific time correlation and management of on-board clocks (or not)</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Symbol">·
        </span><span style=" font-size:11pt;font-family:Calibri">Discussion
of issues and similarities</span><span style=" font-size:12pt;font-family:Calibri">
</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">time
exchange is quite common across agencies</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">time
correlation is challenging, especially at higher levels of accuracy</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">time
synchronization may be workable at millisecond accuracies, but not higher</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">relativistic
time issues</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Symbol">·
        </span><span style=" font-size:11pt;font-family:Calibri">Use
cases for time synchronization:</span><span style=" font-size:12pt;font-family:Calibri">
</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">orbit
insertion</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">docking</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">robotic
collaboration </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">simultaneous
operation</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">science
observations</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">DTN
time needs (order of seconds)</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">DTN
time services for other users (higher precision)</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Symbol">·
        </span><span style=" font-size:11pt;font-family:Calibri">Next
steps</span><span style=" font-size:12pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">Review
notes, provide comments</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">Review
draft Charter, suggest edits</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:10pt;font-family:Courier New">o
   </span><span style=" font-size:11pt;font-family:Calibri">Schedule
WebEx to make progress</span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<p style="margin-top:0px;margin-Bottom:0px"><span style=" font-size:11pt;font-family:Calibri"> </span></p>
<br><tt><span style=" font-size:10pt">_______________________________________________<br>
CESG-All mailing list<br>
CESG-All@mailman.ccsds.org<br>
</span></tt><a href="https://mailman.ccsds.org/cgi-bin/mailman/listinfo/cesg-all"><tt><span style=" font-size:10pt">https://mailman.ccsds.org/cgi-bin/mailman/listinfo/cesg-all</span></tt></a><tt><span style=" font-size:10pt"><br>
</span></tt>
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</PRE>