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<p class=MsoNormal>Dear MHDC WG member,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>The Next Generation Uplink (SLS-NGU) WG is chartered by
CCSDS to develop updates to existing standards and/or to develop new standards
to enable CCSDS member agencies to increase data volume and throughput on the
uplink. Much of the NGU WG work to date has focused on gathering requirements
for this work and providing these requirements to existing CCSDS WGs so that
they can develop solutions to the problem. <o:p></o:p></p>
<p class=MsoNormal> <o:p></o:p></p>
<p class=MsoNormal>NGU WG would like to engage MHDC WG participants in a
discussion on the potential use of data compression to conserve bandwidth on
the uplink. The first order question is: Is it likely that the use of
data compression on the uplink can provide a big enough payoff to warrant
inclusion as a CCSDS NGU standard?<o:p></o:p></p>
<p class=MsoNormal> <o:p></o:p></p>
<p class=MsoNormal>The first step towards answering this question would be for
the NGU WG to assemble a diverse set of upload data sets that are
representative of the type of traffic on Telecommand (TC) link and anticipated
to compress well. Candidate application data for compression on the uplink may
be: work plans, software uploads, FPGA configuration uploads, parameter
table uploads (e.g. star catalogs). Once a reasonable test set has been
assembled, experts such as those on the MHDC WG can suggest suitable
compression approaches and assess compression performance on the test data.
The performance results would provide useful input for agencies to
determine their level of interest in such a TC compression CCSDS standard.<o:p></o:p></p>
<p class=MsoNormal> <o:p></o:p></p>
<p class=MsoNormal>With this in mind, I’m writing to the MHDC WG
participants with the hope of generating some email discussion before the next
meeting in London in Oct. Specifically, I’m interested in your
technical opinion on the opportunity/feasibility of such standardization and to
see who is able to support this initial step.<o:p></o:p></p>
<p class=MsoNormal> <o:p></o:p></p>
<p class=MsoNormal>We hope to also arrange a lunchtime meeting in London
on Monday Oct 25 or Tuesday Oct 26 for anyone interested in continuing the
discussion in person.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thank you and best regards,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Greg Kazz<o:p></o:p></p>
<p class=MsoNormal>Chairman CCSDS SLS-NGU WG<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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