[CESG] IOAG: Service Catalogue #1

Scott, Keith L. kscott at mitre.org
Mon Sep 26 20:06:09 UTC 2016


I think I agree with you.  My concern from the beginning has been that I do not want the forward file service to morph into a way to try to do multi-hop forwarding using file transfers as the ‘data link’ mechanism.  I understood the forward file service to have evolved into a mechanism/semantic for zipping a bunch of stuff together (metadata, data, etc.) to be used by the end system application (the receiver end of the data transfer), with possibly some application semantics layered on top.

In fact, if the forward-XXX services were generalized just a bit, I think they’d cover the DTN emergency command/telemetry case.  Or maybe the DTN emergency commanding service is the forward frame service running over bundles, I hadn’t thought of that until now but I like it.  If part of the CSTS forward-frame service states how to tunnel (in my case, FRAMES) to a remote location and then radiate them, and if it can be run over BP as a transport mechanism…   It would address an IOAG need, at least.


From: "cesg-bounces at mailman.ccsds.org" <cesg-bounces at mailman.ccsds.org> on behalf of Peter Shames <peter.m.shames at jpl.nasa.gov>
Date: Monday, September 26, 2016 at 3:33 PM
To: Nestor Peccia <Nestor.Peccia at esa.int>, CCSDS Exec <cesg at mailman.ccsds.org>
Subject: Re: [CESG] IOAG: Service Catalogue #1


I know that this is a late input, but after reading the IOAG Svc Cat #1 I have a very real concern that I think needs to be surfaced.  Four new services have been introduced, the "Forward/Return CFDP-File Service Type" and the "Forward/Return PACKETS-File Service Type".  In reading through the descriptions I find that they mention certain SM characteristics, but fail to acknowledge the required presence of a whole lot of "packet / file / frame plumbing" that is missing in most of our current systems.  Of particular concern, from a standards and logistics point of view, is that these new standards require a lot of the "plumbing" that CSTS F-Frame is supposed to provide, but make no mention of that standard.  In fact, the precursor standards, "Forward Synchronous Encoded Frame Service Type" has been dropped, and what is left is just some sort of weak "forward reference" to a CSTS F-Frame service.

I think this is a huge mistake and that we should push back on it.

Here is the logic behind this:

1)      FF-CSTS includes the key services and functions that are required for anything like forward file, or forward packet, or forward DTN to work.

2)      These functions include, quoting from the report "Users shall be aware that IOAG Service Catalog 2 foresees a future CSTS Forward Frame Service that is assumed will provide a forward service for [AOS] and [TC-DLP] frames implementing multiplexing, frame fill and coding in the provider and implementing the full stack down to the physical layer."

3)      In order to implement a forward file or packet service all of these functions, plus frame creation, must be present in the service provider.

4)      It makes little technical sense to create forward file and forward packet services, as new separate services that embed all of these function, instead of creating the FF-CSTS service and then building CFDP and Packet service "plug-ins" on top of that which use this underlying service.

In fact, this approach is exactly how the forward file service is now described in the SCCS-ADD.  I draw your attention to CCSDS 901.1-M-1, sec and sec  In fact, fig 6-4 shows the relationships among SM, CSTS F-Frame, the associated functions that are required, including ranging, and also SLE R-AF, and fig 6-8 (ABA ESLT Forward-File Protocol Building Blocks) shows how F-Frame and Fwd frame are designed to be integrated.  Any sort of forward packet service ought to just be a variant of this.

My recommendation is that CCSDS push back on this IOAG Cat 1 request for two new stand alone services and instead argue that CSTS F-Frame should be done first, and these other new service built upon that base.

Regards, Peter

From: CESG <cesg-bounces at mailman.ccsds.org> on behalf of Nestor Peccia <Nestor.Peccia at esa.int>
Date: Thursday, September 15, 2016 at 3:43 AM
To: CCSDS Engineering Steering Group - CESG Exec <cesg at mailman.ccsds.org>
Subject: [CESG] IOAG: Service Catalogue #1


Please let me have your comments (in particular from the CSS Area) by 22nd Sept 2016 cob.


Dear all,

Please  find attached the Service Catalogue #1 that has been approved by the IOAG.

You should be aware that the final approval regarding the editorial updates from NASA is still pending. There is an on-going discussion concerning service management “function” vs. service management “service”.

However, this version is good enough to be processed by the CESG.

[attachment "IOAG Service Catalog One.v2.0-Approved-20160823.pdf" deleted by Nestor Peccia/esoc/ESA]
[attachment "IOAG Service Catalog One.v2.0-Approved-20160823withBars.pdf" deleted by Nestor Peccia/esoc/ESA]

CESG will address this update during our next webex.

Main changes are :

  1.  forward / return CFDP file over terrestrial generic file

  1.  forward / return packet file service  over terrestrial generic file

  1.  Service Management functions


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