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<div>Dear CESG colleagues,</div>
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<div>We published the Reference Architecture for Space Data Systems (RASDS). Magenta Book. Issue 1, in September 2008. According to the CCSDS Procedures Manual, CCSDS A02.1-Y-4 , Sec 6.2.7, it is now time (past time actually) to perform the RASDS Periodic
Review. We will need to restart the System Architecture Working group (SAWG) in order to carry out this work and will be discussing how best to do this within SEA.</div>
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<div>There are several possible outcomes of this review:</div>
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<li>Reaffirm the document as it is</li><li>Make minor technical changes</li><li>Revise it by adding new material (such as a Service or Operations viewpoint)</li><li>Revise it and re-cast using more modern SysML and UML methods to replace / augment the current PPT drawing approach</li><li>Retire the document (Silver status)</li></ol>
<div>Since the document is consistently in the upper 30-40 documents downloaded from the CCSDS web site, and it has been used by a number of different projects and documents both inside and outside CCSDS, it is probably pre-mature to retire it.</div>
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<div>If we decide to take on either option 3 or 4 we understand that it will bear some relationship to other working groups in CCSDS. The Services and Operations viewpoints should be of use to the CSS, MOIMS, and SOIS. The use of SysML and UML will align
the RASDS with the best current Model Based Systems Engineering (MBSE) practices and some of the WG are already using these methods.</div>
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<div>I would like to solicit expressions of interest from the other WG's and the agencies that are represented in CCSDS. If you would like to contribute ideas, approaches, or support please contact me. We will discuss this within the SEA Plenary, but I would
be willing to set up a separate BoF as well to allow more open discusison among interested parties from any WG.</div>
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<div>Thanks, Peter</div>
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