[Sls-slp] Proposed update to Prox-1 GB (CCSDS 210.0-G-2)

[Kazz, Greg (US 312B)]

Dear SLP WG,

The purpose of this email is to fix an inconsistency in the Prox-1 Green Book, to make it consistent with the normative Prox-1 Blue Book. Please see the attached power point file for these changes. Please review the changes in the attached power point file and let me know if you find any problems/issues. I’d like to get your feedback by July 15. I plan to present this change (and any modifications we come up with beforehand) at our Fall 2022 meeting, so that the Prox-1 GB can reflect this change this year. It is probably easier when evaluating this change to simply print out the “current’ and “proposed” figures. I will upload this file to the CWE directory soon.

An inconsistency between the Prox-1 Space Data Link Protocol Blue Book (CCSDS 211.0-B-6) and the Prox-1 GB (CCSDS 210.0-G-2) was brought up to me by the NASA Mars Program. The inconsistency exists in the current Prox-1 Green Book in Section 4.1.3 and the accompanying Figure 4-3. The inconsistency is that the Green Book states and shows that when a user chooses to immediately move from the hailing channel and on to a working channel, there is an incorrect intermediate step in which the first frame transmitted by the responding node is currently documented as using the hailing channel. This is in contrast to what is documented in the relevant Prox-1 blue book state table and figure that defines this activity in Section 6.4.2, Figure 6-1 and Table 6-7. (Note that NASA’s Electra transceiver, both Orbiter and lander versions comply with the Prox-1 Blue Book in this regard). See next paragraph.

[Prox-1 Blue Book ] In event E3 in Table 6-7, when the responder receives the hailing directives, it is stated that the receiver and transmitter parameters are set as per the hail directives. Therefore the responder changes its transmitter to the working frequency. Note that this event happens before the responder sends its first frame back to the caller. The consequence in this case is that the responder sends the first frame on the working frequency, and the caller must change its receiver to the working frequency beforehand.

[Prox-1 Green Book] In section 4.1.3 and figure 4-3, I’ve taken a stab at updating both the figure and the text to match the Prox-1 blue book.

Best regards,
Chair SLP WG

Greg Kazz
Principal Engineer
Technical Group Supervisor,
312B Project Protection, Project Software, and End to End Information System Engineering
Jet Propulsion Laboratory
4800 Oak Grove Dr., M/S 301-490
Pasadena, CA 91109
1+(818)393 6529(voice)
1+(818)393 6871(fax)
email: greg.j.kazz at jpl.nasa.gov

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.ccsds.org/pipermail/sls-slp/attachments/20220629/f1041830/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: fd_link_est2_wc_GB_June_28_2022.ppt
Type: application/vnd.ms-powerpoint
Size: 108544 bytes
Desc: fd_link_est2_wc_GB_June_28_2022.ppt
URL: <http://mailman.ccsds.org/pipermail/sls-slp/attachments/20220629/f1041830/attachment-0001.ppt>