[CESG] New Work Item Announcement: CFDP Refresh WG

Scott, Keith L. kscott at mitre.org
Fri Aug 2 08:58:49 EDT 2013


Chris,

I think I know how to address Gipo's concerns, though I need some technical assistance from Brian to effect those (I'll send Brian an email in a minute with those -- they're easy, I think).  So there's nothing stopping *formation* of the CFDP refresh WG.  If WG formation happens ahead of what I put in the framework, great, they can start right away.  I do agree with Gipo that for the refresh WG some of the Green Book changes can't really happen until the Blue Book is well-along, but moving the Green Book work to later just supports your desire to get the draft Blue Book out early.

Realistically I don't think the proposed Pink Sheet work will hold up the refresh WG *at all*.  There's draft text for the pink sheet done, and I would be very surprised if there were any dissent over it.  The change to the existing CFDP spec is simply to allow an existing, already tested functionality to occur in another context, and there's *no protocol impact* (to CFDP) if that interaction somehow doesn't happen, or fails [i.e. once the finished PDU is sent, that's it as far as CFDP is concerned -- failure of the PDU to arrive does not trigger further protocol action].

NASA has a need for the Pink Sheet modification in order to press for deployment of DTN on ISS (they'd like to advocate for Class-1 CFDP with the Pink Sheet addition over BP).  The negotiations for that deployment are in the works now, and having the updated capability will make CFDP a much more viable candidate for file transfer.

To ensure that the pink sheet doesn't delay the refresh WG, I propose that SIS apply for a waiver of the interoperability test requirement for the Pink Sheet modification from the CESG, with the agreement and understanding that we will in fact perform interoperability testing in conjunction with the 5-year refresh interoperability testing (which I am assuming will make larger changes to the protocol).  This will let the pink sheet go forward with the technical reviews (which should be easy, I think there are only about 20 lines of text in the whole pink sheet, and many of them are just adding the ability to request the finished pdu to the service interface).  The members of the refresh WG can review the change, but won't have to stop their work and do another set of interoperability tests, and can move forward with all deliberate speed to try to get a draft blue book on the table by the end of the year.

Would that work?

		--keith



Dr. Keith Scott					Office: +1.703.983.6547
Principal Engineer, E535				kscott at mitre.org
The MITRE Corporation
M/S H300
7515 Colshire Drive
McLean, VA 22102

Area Director, CCSDS Space Internetworking Services

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-----Original Message-----
From: Chris.Taylor at esa.int [mailto:Chris.Taylor at esa.int] 
Sent: Thursday, August 01, 2013 9:21 AM
To: Scott, Keith L.
Cc: Brian Oliver (ccsds_techsupport at aiaa.org); CCSDS Engineering Steering Group - CESG Exec (cesg at mailman.ccsds.org); cesg-bounces at mailman.ccsds.org
Subject: Re: [CESG] New Work Item Announcement: CFDP Refresh WG

Keith, I may have missed some traffic on this topic here but for the CFDP
updates there are another couple of parameters coming into play here in ESA:

Our Euclid project has adopted CFDP and specs will have to be sent out to
industry for the development. We have a period of grace until the end of the
year but after that we will have some real issues if the new Blue book is not
on the table (at least in draft form)

I have support for Dai for this year but not for next, and if I don't place
the contract with him shortly, I will lose the budget completely

I have support for the modification and interoperability testing  for the
next 9 months but after that the picture is not rosy

When I see your proposal below and a couple of the other discussions we seem
to be stretching out the work to a point that it will be incompatible with
the above constraints.  I'm therefore quite concerned.

Another point I would make is that extended procedures really complicate the
documents and lead to a serious "wood for trees" problem. Removing  these
first will make the other changes trivial and also make the spec far more
readable.

My plea here is to get moving asap on agreeing the changes and do it all in
one go in one working group. Otherwise, I really fear we will not have the
resources available to support the WG and equally importantly Euclid will
have to deviate from the CCSDS spec.

Please could you reconsider,

Regards,
//ct



                                                                                                                                              
  From:       "Scott, Keith L." <kscott at mitre.org>                                                                                            
                                                                                                                                              
  To:         "Brian Oliver (ccsds_techsupport at aiaa.org)" <ccsds_techsupport at aiaa.org>,                                                       
                                                                                                                                              
  Cc:         "CCSDS Engineering Steering Group - CESG Exec \(cesg at mailman.ccsds.org\)" <cesg at mailman.ccsds.org>                              
                                                                                                                                              
  Date:       29/07/2013 15:44                                                                                                                
                                                                                                                                              
  Subject:    [CESG] New Work Item Announcement: CFDP Refresh WG                                                                              
                                                                                                                                              
  Sent by:    cesg-bounces at mailman.ccsds.org                                                                                                  
                                                                                                                                              





Dear Tech Support,

The CFDP Refresh WG has passed CESG poll with one outstanding item that I am
confident we can address.  Can you please place an item in the New Work Item
Announcements section:

                        --keith

======

CFDP Refresh Working Group
The SIS Area has chartered a working group to update/refresh the CFDP
specification as required by CCSDS.  The WG charter and list of projects is
available on the CWE Framework.  There is a forum on the CCSDS Wiki to
discuss the WG, as well as a Wiki page with notes from the Bordeaux Bof
(primarily a list of things that the WG might like to consider as changes to
CFDP).

Items to consider for the CFDP update include:
      *       Increasing the maximum size of files transferred by CFDP and/or
      the maximum size of the PDUs used by CFDP
      *       Eventually retiring the SFO, Extended Procedures, and
      Acknowledged Procedures in favor of CFDP / BP (though possibly not in
      this update)
      *       Adding per-segment metadata to increase the value of isolated
      File Data segments that are received individually
      *       Enabling identification of record boundaries in received files.
      (Currently record boundaries must be coterminous with segment
      boundaries, so long records can't be identified.)
      *       Identifying the type/format of data (e.g ASCII, EBCDIC, OTHER)
      *       Support for compression




Dr. Keith Scott
Office: +1.703.983.6547
Principal Engineer, E535
kscott at mitre.org
The MITRE Corporation
M/S H300
7515 Colshire Drive
McLean, VA 22102

Area Director, CCSDS Space Internetworking Services

MITRE self-signs its own certificates.  Information about the MITRE PKI
Certificate Chain is available from http://www.mitre.org/tech/mii/pki/

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