[Sea-sa] FW: [EXTERNAL] Re: CCSDS Review of CCSDS 311.0-P-1.1, Reference Architecture for Space Data Systems

Mon Aug 12 22:19:14 UTC 2024

Input on the RASDS document.  Add it to the RID list for disposition.

Peter

From: Marc Blanchet <marc.blanchet at viagenie.ca>
Date: Wednesday, August 7, 2024 at 5:44 PM
To: Shames, Peter M (US 312B) <peter.m.shames at jpl.nasa.gov>
Subject: [EXTERNAL] Re: CCSDS Review of CCSDS 311.0-P-1.1, Reference Architecture for Space Data Systems
Forgot one thing:
- I found the discussion on SANA a bit skim. In a system architecture for space, it seems that SANA should have a central role. At its current form, but also as certificate authority, as the implementation of several of the concepts presented in the book.

Marc.

Le 7 août 2024 à 20:42, Marc Blanchet <marc.blanchet at viagenie.ca> a écrit :

Hello,
 Well, it was loooong. Frankly, I skimmed some sections. This document is pretty comprehensive but a bit too high level for me. I guess the pragmatic in me is a bit far from those high-level representations. Anyway, a few comments:
- in connectivity section, there is a discussion on performance and processor speed, … On IP, people often confuse the ability of a router to fill out the pipe vs its ability to actually process the packets. The latter is way more important and is the real good metric: the forwarding rate: number of packets per second that can be processed. Might want to talk about that. That is also what will differentiate IP vs BP for high speed: to reach a good forwarding rate, one need to do hardware processing which is only handled by having fixed size headers and fixed size fields within the header, without any extension headers. I’ve worked with many hardware vendors back in the 90’s and they were quite clear: "if a packet contains an extension header, we just drop it. » Because it cannot be memory-mapped efficiently, therefore it will be sent to the (slow) central CPU (instead of being processed on the line card) and if someone sends multiple of these packets on the network, it will put the whole router onto its knees: aka an easy denial of service attack. Lessons learned by real hardware experts. Something that was never ever discussed for BP (well, I actually raised the point a few times but they just discard the comment).
- typo: TCP: not Transport Control Protocol but Transmission Control Protocol
- obviously I would claim that what is missing is the ability of the IP stack to work in deep space/dtn, which is not mentioned. But we have had that debate… ;-)
- examples of TCP are ok, including its state diagram (annex C). But this is more « textbook ». In reality, TCP is fading away fast in favour of QUIC. I understand this was just an example.

I was impressed of not seeing typos!

I’m not sure I did the review at the level you were expecting.

Regards, Marc.

Le 3 juill. 2024 à 20:15, Shames, Peter M (US 312B) <peter.m.shames at jpl.nasa.gov> a écrit :

Dear Systems Architecture colleagues,

We have just completed a thorough revision of the CCSDS document Reference Architecture for Space Data Systems (RASDSv2).   It is now out for wide review within the international community of space agencies, affiliate organizations, and related experts.  This document leverages the systems architecture precepts from ISO 42010 (Software, Systems, and Enterprise – Architecture Description) and also the earlier ISO 10746 (Information Model, Open Distributed Processing).

The updated document includes revised Enterprise, Functional, Deployment, Protocol, and Information viewpoints, and new Service, Operation, and Structural viewpoints.  There is now a complete abstract ontology of the objects that appear in each viewpoint and their direct and correspondence relationships.  And there is also a new Annex showing examples of how to represent the RASDS viewpoints and objects using SysML modeling approaches.

This is an open review and I would like to encourage you, and any others who might be interested, to participate and provide feedback.  The links are in the following email.  Feel free to forward this to any of your colleagues who might have an interest.

Thanks in advance for your support.

Peter Shames

Peter Shames
Consultative Committee for Space Data Systems (CCSDS)
Systems Engineering Area Director
Jet Propulsion Laboratory / Interplanetary Network Directorate
4800 Oak Grove Drive
MS 301-490
Pasadena, CA 91109

peter.m.shames at jpl.nasa.gov<mailto:peter.m.shames at jpl.nasa.gov>
C: 818-687-7901
https://cwe.ccsds.org/sea/default.aspx<https://urldefense.us/v3/__https:/cwe.ccsds.org/sea/default.aspx__;!!PvBDto6Hs4WbVuu7!fgncIVD-iu0I_1xWlmq78lUqf1aK_WZzB2gUhx7cfOlLefMQluIGVhXTKIrzYkYoUsYraXcV$>

From: US-TAG13 <us-tag13-bounces at mailman.ccsds.org<mailto:us-tag13-bounces at mailman.ccsds.org>> on behalf of NASA Data Standards Program Support via US-TAG13 <us-tag13 at mailman.ccsds.org<mailto:us-tag13 at mailman.ccsds.org>>
Date: Monday, July 1, 2024 at 1:35 PM
To: us-tag13 at mailman.ccsds.org<mailto:us-tag13 at mailman.ccsds.org> <us-tag13 at mailman.ccsds.org<mailto:us-tag13 at mailman.ccsds.org>>
Cc: NASA Data Standards Program Support <thomas.gannett at tgannett.net<mailto:thomas.gannett at tgannett.net>>
Subject: [EXTERNAL] [Us-tag13-Interest] CCSDS Review of CCSDS 311.0-P-1.1, Reference Architecture for Space Data Systems
Control Number: IRP 24-16

The following draft CCSDS Recommended Practice has been placed on line and is available for US-TAG13 review:

     CCSDS 311.0-P-1.1. Reference Architecture for Space Data
                        Systems. Pink Book. Issue 1.1. June 2024.

DOCUMENT DESCRIPTION:  Reference Architecture for Space Data Systems (RASDS) is intended to provide a standardized approach for description of data system architectures and high-level designs, which individual CCSDS working groups may use within CCSDS. This draft update is an extended approach, RASDSv2, specifically adapted for the space domain and aligned with best current practices in the fields of system and software architecture and modeling.

The review document, in Portable Document Format (PDF), and associated review materials are available for downloading at the following location:

     https://urldefense.us/v3/__https://public.ccsds.org/review/CCSDS*20311.0-P-1.1/default.aspx__;JQ!!PvBDto6Hs4WbVuu7!PrU7bdUKxxK5FrIj7FIRjf4CwmjlTs0Jl3-EPVAthNcnLzXXaznGBHnfmZYxnD-X9rBn3zGJl8b6f1dm8ukxrf-Oh6lry4FU$<https://urldefense.us/v3/__https:/public.ccsds.org/review/CCSDS*20311.0-P-1.1/default.aspx__;JQ!!PvBDto6Hs4WbVuu7!PrU7bdUKxxK5FrIj7FIRjf4CwmjlTs0Jl3-EPVAthNcnLzXXaznGBHnfmZYxnD-X9rBn3zGJl8b6f1dm8ukxrf-Oh6lry4FU$>

US-TAG13 review comments should be submitted on or before 16 August 2024 to the US-TAG13 Chairman:

                    Email: secretariat at mailman.ccsds.org<mailto:secretariat at mailman.ccsds.org>

_______________________________________________
US-TAG13 mailing list
US-TAG13 at mailman.ccsds.org<mailto:US-TAG13 at mailman.ccsds.org>
https://urldefense.us/v3/__https://mailman.ccsds.org/cgi-bin/mailman/listinfo/us-tag13__;!!PvBDto6Hs4WbVuu7!PrU7bdUKxxK5FrIj7FIRjf4CwmjlTs0Jl3-EPVAthNcnLzXXaznGBHnfmZYxnD-X9rBn3zGJl8b6f1dm8ukxrf-OhzQ0ot0D$<https://urldefense.us/v3/__https:/mailman.ccsds.org/cgi-bin/mailman/listinfo/us-tag13__;!!PvBDto6Hs4WbVuu7!PrU7bdUKxxK5FrIj7FIRjf4CwmjlTs0Jl3-EPVAthNcnLzXXaznGBHnfmZYxnD-X9rBn3zGJl8b6f1dm8ukxrf-OhzQ0ot0D$>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.ccsds.org/pipermail/sea-sa/attachments/20240812/48f7da43/attachment-0001.htm>