[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 12:56:41 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??

PS#2 Remebering also that - as per your citation - "...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..."




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 





-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ccsds.org/pipermail/cesg/attachments/20110131/94ca8025/attachment-0001.html


More information about the CESG mailing list