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<p class="MsoNormal">Dear Tomaso, et al,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">During today’s CMC meeting the question came up of the origins of the Last Hop / First Hop service. Regardless of which Area or WG takes this work up, I thought it worthwhile to share the document that defined this service, along with
the rationale for it.<o:p></o:p></p>
<p>This was studied in 2010 as part of the IOAG Space Internetworking Strategy group (SISG). It was intended as a service to “<span style="font-size:12.0pt">determine how the SSI will handle services for spacecraft that do not or cannot implement SSI user
node functions</span>”. This explicitly includes SSI nodes that need to be “rebooted” using link layer / emergency commands, as well as nodes that are not DTN nodes, but that could benefit from using a higher speed DTN relay service than their own DTE/DFE
link can support.<o:p></o:p></p>
<p>For the record, the attached document is what was published by the IOAG back in 2010.<o:p></o:p></p>
<p>Cheers, Peter<o:p></o:p></p>
<p><o:p> </o:p></p>
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