....is the right answer! Many thanks for this Jane, it is exactly what we need.<BR><BR><BR>
<HR>
Fellas,<BR><BR>Here's my 2 cents......<BR>When I started with the TCONS WG, I didn't know much (actually nil) aboutnetworks nor did I have a great desire to learn the details of all theprotocols. However, as a software systems engineer, I was drawn tothe fact that TCONS was trying to provide a GENERIC INTERFACE to theunderlying busses, which makes my life as an applications developer somuch easier. To me, TCONS abstracted the differences among thedifferent protocols and busses, and allowed me to write PORTABLEsoftware. That translates into less risk, cost, and schedule, wordsthat missions understand. I think Steve's bullet #3 hits the nailon the head. I've been espousing these points to missions and theyare buying into it. We (software people) are tired of rewritingsoftware for the same hardware, never mind different hardware, becauseeveryone wants to do it "their way". IF, like Dai said,there was someplace to go that standardized th!
is whole
mush of stuff,many would jump on the bandwagon. The SOIS acronym is no longer astrange one to software people here in my branch that are doing MISSIONwork. No one cares about the underlying protocols so much as thefact that there's a well-defined interface regardless of the underlyingbus.<BR><BR>Now for the technical 2 cents......we did our Ethernet prototype usingthat much beleaguered UDP/IP both for guaranteed and scheduledservice. Of course this prototype didn't have the APIs implemented,but I don't think it would be a stretch to update. We can/should discussthe prototype, the resulting data, and the "reliable UDP" inAthens. My point is that we ran what we functionally thought was a TCONSarchitecture using that darned IP protocol, and found it to be quitestraightforward. I expect the same for SpaceWire. <BR>Perhaps we should just say we can't accommodate ALL busprotocols......and stop wasting 80% of our time on 20% of theproblem. Like TM/TC, !
is
doesn't fit every scenario, but is used forat least 90% of our data. The other 10% has to be addressed eachmission, but that's a hell of a lot better than rewriting for 50% or moreeach mission.<BR><BR>And so it goes.<BR>Jane<BR><BR>At 11:42 PM 4/5/2005 +0200, Chris Plummer wrote:<BR><BR>
<BLOCKQUOTE cite="" type="cite"><FONT face=arial color=#000080 size=2>HiSteve,<BR></FONT><BR><FONT face=arial color=#000080 size=2> <BR></FONT><BR><FONT face=arial color=#000080 size=2>The sort of thing we need issomething that will sell TCONS to a project manager. That means that itneeds to be less than three minutes long verbally (including the 2 minutephone call interruption) and must be no more than 2 A4 pages of printedmatter of which at least one and a half pages should be cartoons andwords should be in 18 point text minimum. The emphasis must be on howTCONS will make that project managers life more endurable, which meansthat there is no real room for technical arguments, and certainly noscope for a bitching session about TCP/IP. To do that you need to try tofeel the way that project manager feels.<BR></FONT><BR><FONT face=arial color=#000080 size=2> <BR></FONT><BR><FONT face=arial color=#000080 size=2>Seriously, CCSDS secretariatnow includes professional PR !
and
marketing support. If we can get TCONSthrough next week I think we should start try to get some input from thatfunction!<BR></FONT><BR><FONT face=arial color=#000080 size=2> <BR></FONT><BR><FONT face=arial color=#000080 size=2>Cheers,<BR></FONT><BR><FONT face=arial color=#000080 size=2> Chris.<BR></FONT><BR><FONT face=arial color=#000080 size=2> <BR>
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<DIV align=center></FONT><br><FONT face=tahoma size=2><B>From:</B> Steve Parkes[<A href="mailto:sparkes@computing.dundee.ac.uk" eudora="autourl">mailto:sparkes@computing.dundee.ac.uk</A>]<BR><B>Sent:</B> 04 April 2005 18:03<BR><B>To:</B> Chris Plummer<BR><B>Cc:</B> 'Patrick.Plancke@esa.int'; 'sois-tcons@mailman.ccsds.org'<BR><B>Subject:</B> SOIS TCONS<BR></FONT><BR><FONT face="Times New Roman, Times"> <BR></FONT><BR><FONT face=arial size=2>Chris,<BR></FONT><BR><FONT face=arial size=2> <BR></FONT><BR><FONT face=arial size=2>Following on from the last teleconference,could you let me know what else you need besides the slides that I havealready provide, after your previous request?<BR></FONT><BR><FONT face=arial size=2> <BR></FONT><BR><FONT face=arial size=2>Some thoughts about USPs for TCONS:<BR></FONT><BR><FONT face=arial size=2>-</FONT><FONT size=1> </FONT><FONT face=arial size=2>Provides various traffic
classesappropriate for onboard use<BR></FONT><BR><FONT face="Courier New, Courier" size=2>o</FONT><FONT size=1> </FONT><FONT face=arial size=2>Best effort with priority<BR></FONT><BR><FONT face="Courier New, Courier" size=2>o</FONT><FONT size=1> </FONT><FONT face=arial size=2>Guaranteed delivery with priority<BR></FONT><BR><FONT face="Courier New, Courier" size=2>o</FONT><FONT size=1> </FONT><FONT face=arial size=2>Scheduled delivery (deterministic)<BR></FONT><BR><FONT face=arial size=2>-</FONT><FONT size=1> </FONT><FONT face=arial size=2>Can carry other protocols (e.g. TCP/IP)without upsetting time-critical traffic<BR></FONT><BR><FONT face=arial size=2>-</FONT><FONT size=1> </FONT><FONT face=arial size=2>TCONS maintains the following featureswhich m!
ay also
be present in other protocols:<BR></FONT><BR><FONT face="Courier New, Courier" size=2>o</FONT><FONT size=1> </FONT><FONT face=arial size=2>Generic interface to applicationsoftware across different underlying buses/networks<BR></FONT><BR><FONT face="Courier New, Courier" size=2>o</FONT><FONT size=1> </FONT><FONT face=arial size=2>Interoperability<BR></FONT><BR><FONT face=wingdings size=2>§</FONT><FONT size=1> </FONT><FONT face=arial size=2>Software interoperability via APIdefinition<BR></FONT><BR><FONT face=wingdings size=2>§</FONT><FONT size=1> </FONT><FONT face=arial size=2>Equipment interoperability via PDU andprotocol definition<BR></FONT><BR><FONT face=arial size=2> <BR></FONT><BR><FONT face=arial size=2>Regards<BR></FONT><BR><FONT face=arial size=2> <BR></FONT><BR><FONT face=arial
size=2>Steve<BR></FONT><BR><FONT face=arial size=2> <BR></FONT><BR><FONT face="Times New Roman, Times">------------------------------------------<BR></FONT><BR><FONT face="Times New Roman, Times">Steve Parkes<BR></FONT><BR><FONT face="Times New Roman, Times">Space Systems Research Group<BR></FONT><BR><FONT face="Times New Roman, Times">Applied Computing, University ofDundee<BR></FONT><BR><FONT face="Times New Roman, Times">Dundee</FONT>, DD1 4HN, Scotland,UK<BR><BR><FONT face="Times New Roman, Times">Tel: +44 1382 345194<BR></FONT><BR><FONT face="Times New Roman, Times">Fax: +44 1382 348838<BR></FONT><BR><FONT face="Times New Roman, Times">Mobile</FONT>: +44 784 138 3779<BR><BR><FONT face="Times New Roman, Times"> <BR></FONT>_______________________________________________<BR>Sois-tcons mailing list<BR>Sois-tcons@mailman.ccsds.org<BR><A href="http://mailman.ccsds.org/mailman/listinfo/sois-tcons"
eudora="autourl">http://mailman.ccsds.org/mailman/listinfo/sois-tcons</A></BLOCKQUOTE><BR>--<BR><BR><br>