[CESG] RE: CCSDS 131.4-R-0 bis,
TM Channel Coding Profiles for CCSDS Agency review
Gian.Paolo.Calzolari at esa.int
Gian.Paolo.Calzolari at esa.int
Mon Jan 31 12:54:36 EST 2011
Adrian,
sorry for not replying too quickly but I was travelling with
limited e-mail access and I am just back to Darmstadt.
Very concisely then:
- The proposed document has consensus as the previous version had (as CESG
agreed to freeze the conflictual issue for which only NASA withdrew in
London the full consensus previously expressed).
- Nobody withdrew the consensus to the main document originally expressed
in London.
- No normative part did change
- My remark about the "lively" discussion went back to the London Meeting.
Regards
Gian Paolo
PS What do you mean with ?convergence??
From:
"Hooke, Adrian J (9000)" <adrian.j.hooke at jpl.nasa.gov>
To:
"Gian.Paolo.Calzolari at esa.int" <Gian.Paolo.Calzolari at esa.int>
Cc:
"cesg at mailman.ccsds.org" <cesg at mailman.ccsds.org>
Date:
28-01-2011 15:24
Subject:
RE: CCSDS 131.4-R-0 bis, TM Channel Coding Profiles for CCSDS Agency
review
Gian Paolo: could you please clarify the status of this proposed document
in terms of whether or not it reflects consensus? You used the word twice:
1. ?It is also worth mentioning that a careful analysis of all
comments produced during the previous CESG e-poll have been discussed with
the Book Editor and the approach taken in the book with complete WG
consensus has been compared against other approaches to confirm its
validity?
2. ?Despite sometimes the debate was very active, comments were
lively discussed finding convergence versus full WG consensus.?
Does Item 2 imply that you used some process called ?convergence? rather
than the required process of consensus? As a reminder, the CCSDS procedure
manual is quite clear on this point:
5.1.2 CONSENSUS
The decisions of all CCSDS organizational units shall reached through
consensus. In this context, consensus does not necessarily mean that
unanimous agreement has been reached, but that the result incorporates the
best set of compromises to which all parties can agree
5.2.5 WORKING GROUP MEETINGS
5.2.5.1 Purpose
Working Group meetings are convened to enable face-to-face technical
discussions leading to consensus.
Please clarify whether or not the revised document does in fact represent
full Working Group consensus.
Best regards
Adrian
Adrian J. Hooke
Chairman, CCSDS Engineering Steering Group (CESG)
Space Communications and Navigation Office (SCaN)
Suite 7L70
Space Operations Mission Directorate
NASA Headquarters
Washington DC 20024-3210
From: Gian.Paolo.Calzolari at esa.int [mailto:Gian.Paolo.Calzolari at esa.int]
Sent: Friday, January 28, 2011 2:58 AM
To: Hooke, Adrian J (9000); Nestor.Peccia at esa.int
Cc: CCSDS Secretariat; cesg at mailman.ccsds.org
Subject: CCSDS 131.4-R-0 bis, TM Channel Coding Profiles for CCSDS Agency
review
Dear Adrian and Nestor,
I am asking you - CESG Chair and Deputy CESG Chair - to poll the
CESG as soon as possible to authorize the CCSDS Agency review for the
attached revised version of the TM Channel Coding Profiles proposed Draft
Magenta Book.
The document includes improvements according to the comments gathered
during the previous CESG e-poll.
It is also worth mentioning that a careful analysis of all comments
produced during the previous CESG e-poll have been discussed with the Book
Editor and the approach taken in the book with complete WG consensus has
been compared against other approaches to confirm its validity. As an
example, the Report of the Space Internetworking Strategy Group
(originally produced on 15 November 2008 and revised July 2010) was
checked keeping in mind that the purpose of the two documents (SISG Report
vs. TM Coding Profiles) is very different with the proposed Magenta Book
focusing on actual recommendations limited to Telemetry while the SISG
Report addresses (in "Appendix G: The Scenario Template Table") a much
wider scenario (e.g. the accent on TC and space-to-link is not minor) with
a reporting and forecast approach.
The SISG report takes into accounts different "Mission Types" but finally
for Direct To Earth (DTE) links identifies always the same frequency bands
(S, X, Ka) with no granularity while the approach used in the Magenta is
just more accurate according to expectation, focus, pertinence and
expertise of the Space Link services Area.
The SISG Table is "lumping together S-Band, X-band and Ka-band
frequencies" in the row Frequency Band DTE, for both Mission Type "Earth
Exploration Missions" and "DTE/DFE Science Missions"while the related
?Coding DTE? rows are different. Therefore is NOT a surprise (as
criticized) that the Magenta book proposes different types of codes.
The (criticized) overlapping of the scenarios in a few cases is natural
since missions belonging to different categories can have the same type of
orbit. If the categorization would start from orbit types, the overlapping
would just fall into the frequency ranges. Validity if of the Magenta book
is also confirmed by an analysis of the four Mission types identified in
the SISG Report (i.e. Earth Observation Missions, excluding geostationary
satellites; Lunar Missions; DTE/DFE Science Missions and Mars Missions):
the Magenta Book identifies 2 types (Earth Exploration and Space Research
with the latter split in 2 sub-types depending on the distance from Earth)
but the correspondence is obvious and the higher SISG granularity was
important to the target of that group but not those of the Magenta Book.
In fact the ?Coding DTE? rows related to the last 3 SISG types are
identical stating only the high level types of codes with a level of
detail clearly not sufficient for the Magenta Book target (i.e. taking the
SISG approach the Magenta Book would just fail).
Therefore I consider that the Coding and Synchronization Working Group did
an excellent job in producing this draft Magenta Book that represents a
very focused exercise with very effective results.
Despite sometimes the debate was very active, comments were lively
discussed finding convergence versus full WG consensus.
It is also IMPORTANT to remember that, as per CESG agreement in London,
the Earth Exploration column of Table 3-1 (i.e. clauses 3.2.3 and 3.2.5)
is not going to be subject to Agency Review (i.e. no RID on those two
clauses will be acceptable).
Thank you for your collaboration and best regards
Gian Paolo Calzolari
SLS-C&S Chair
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