[CMC] RE: [Secretariat] [CESG] Re: CCSDS report to IOAG-11

[Kearney, Mike W. (MSFC-EO01)]

I would recommend changing "Earth Observation Missions" to "Earth
Orbital Missions" to be more generic.  But that's an editorial comment.
Overall, it's a sound recommendation.   

 

   -=- Mike

 

Mike Kearney

NASA MSFC EO-01

256-544-2029

 

From: secretariat-bounces at mailman.ccsds.org
[mailto:secretariat-bounces at mailman.ccsds.org] On Behalf Of Adrian J.
Hooke
Sent: Tuesday, June 12, 2007 7:48 PM
To: Chris.Taylor at esa.int
Cc: CCSDS Management Council; greg.kazz at jpl.nasa.gov; kscott at mitre.org;
CCSDS Engineering Steering Group - ADs
Subject: [Secretariat] [CESG] Re: CCSDS report to IOAG-11

 

At 08:45 AM 6/12/2007, Chris.Taylor at esa.int wrote:



Adrian, there are some very positive things here and in line with our
thinking.
For the bit stream HDLC I have restate that running IP in this way as a
cross-supported service should be not mandated by CCSDS. 


Chris: I believe that if the Constellation Program persists in its
intention to use this non-standard mode, then there is very little that
a standards organization can do to stop them. However, the space network
operators can specify just what techniques will be cross-supported
internationally. Many people feel that "Option 3" on page 17 of Draft-4
is the appropriate response, i.e., there will be no cross support of IP
per se, but the Agencies *will* support at the SLE/AOS Frame level.




AOS defined this service as delivering a stream of bits, not as
delivering a packet, other services are used for packet delivery. As
implemented on ISS the AOS  bit stream service turned out to be one of
the biggest headaches we had, but fortunately, even there,  it was never
used as a x-supported service and only for private internal Agency data.
I firmly believe this is where it belongs and if Agencies want to use it
privately then this is fine by me.


That's exactly what Option-3 achieves.




Where I can agree is on the need to develop an evolutionary path for the
use of IP. I think one of the main issues with the previous work by SIS
was that it was too visionary and targeted at systems too far in the
future. It was therefore very difficult for other Agencies to contribute
as our missions are much less ambitious and do not have the requirements
to which SIS was offering solutions.  As you may recall, this was the
reason that we initiated the work on the near term Mars mission.
Essentially, we knew that we could not change too much but still needed
to improve matters and provided a way forward. We therefore limited the
scope of the work to the existing infrastructure + the known missions in
the next 15 years.


OK, I agree on the need to develop a pragmatic, evolutionary,
transitional strategy. I've sketched-out the draft terms of reference of
a proposed new Working Group (attached). Comments?




We will very soon, next week or so, deliver draft outputs from the Mars
work (corrected Green and a Magenta book on the X-support services,
including  a PICs proforma).  If the CCSDS could use this approach as a
model to build on, then I think we have a solid way forwards to which we
could sign up to.


Excellent; I'd suggest that we get a draft Mars Recommended Practice out
for review, but we that don't finalize it until we get our hands around
the whole job - Earth, Moon and Mars.

///adrian

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