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<font color="#0000FF">At 08:06 PM 2/19/2009, Kazz, Greg J wrote:<br>
<blockquote type=cite class=cite cite="">Go to SIS-IPO then to Draft
Documents or use the URL below:<br>
The file name is:
702x1r3[final]_Feb19_09_gjk.doc</font></blockquote><br>
Greg: as you know, the IOAG has chartered a Space Internetworking
Strategy Group (SISG) to develop the recommended approach for
transitioning the international community towards an internetworked space
communications architecture. I think that there is a potential SISG issue
with the direct multiplexing of IPv4 datagrams into CCSDS frames
("Method-1" on page 1-1 of the draft). <br><br>
The SISG discussed this yesterday on a videoconference and I believe that
the emerging consensus is that direct IPv4 multiplexing should
<font color="#0000FF"><b>not</b></font> be cross-supported by the IOAG
agencies. Basically, the provisional recommendation is that
<font color="#0000FF"><b>all</b></font> Network layer data structures
(e.g., Ipv4, IPv6 and BP/LTP) should use the Encapsulation
service.<br><br>
This is not an issue with the CCSDS standard (which describes a technical
capability), but an issue with how the standard will be applied in
operational, international cross support. However, we need to
think-through whether (as a minimum) we should add some wording to the
Draft Red Book to point-out this operational constraint, or whether we
should even go far as to remove the direct multiplexing capability for
IPv4.<br><br>
I'd like to get the sense of the IPO working group about how to handle
this. We also have a private SISG meeting scheduled for 16-17 April in CO
Springs and I think that we should plan on having you participate in that
meeting to make sure that we don't have any IOAG/CCSDS disconnects prior
to finalizing the IP-over-CCSDS Links document.<br><br>
Best regards<br>
Adrian<br>
<x-sigsep><p></x-sigsep>
<font size=2>Adrian J. Hooke<br>
Chairman, CCSDS Engineering Steering Group (CESG) and<br>
CCSDS Technical Liaison to the IOAG<br>
NASA Headquarters<br>
Space Communications and Navigation Office, 7L70<br>
Space Operations Mission Directorate<br>
Washington, DC 20546-0001<br>
Office:<x-tab> </x-tab>(+1) 202.358.0097<br>
Mobile:<x-tab> </x-tab>(+1) 818.653.9553<br>
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