RE: FEB BB changes impacts on FLUTE and NORM

Hi Rod,

1) DVB agreed corrected schema yesterday, so you probably do not have the most up-to-date (but for reasons which are obscure to me they did not agree to align with 3GPP/IETF).

3) So you think the Standards Track docs should not even make *informative* references to the Experimental ones ? Even just to state that they are backwards compatible with them ? The reference would be in the "Informative References" section. I thought that the ban of referencing Experimental documents was for Normative References only ?

4) The link between the OTI elements in the FDT and the OTI elements in the EXT-FTI is preserved in the sense that both FDT elements and EXT-FTI elements are defined (semantically) in the FEC BB - i.e. both FDT OTI and EXT-OTI point to FEC BB, rather than FDT OTI pointing to EXT-FTI.

Regards...Mark

-----Original Message-----
From: [email protected] [mailto:[email protected]] 
Sent: Friday, September 16, 2005 10:15 AM
To: Mark Watson; [email protected]; [email protected]
Subject: RE: FEB BB changes impacts on FLUTE and NORM

Please see in-line... 

>1) OK - new schema will be checked and taken in if fine
>
>MW: Make sure you get the new one that was agreed last week 
>(ftp://ftp.3gpp.org/tsg_sa/WG4_CODEC/TSGS4_36/Docs/S4-050641.zi
p). Additionally, the Schema in the FLUTE RFC is not valid >according to XML. 3GPP took the liberty of writing down what 
>they thought the FLUTE FDT Schema 'ought' to be if it was 
>modified to be valid XML, so I would suggest starting with that.

I have this, the DVB one and the original produced by Jani, Sami, Magnus and myself which went into the 3GPP CR. Don't worry, if there's a bug it will not be in the IETF! (Otherwise, I'll be looking for a sponsor to provide an edible hat :)

>2) Perhaps the whole EXT_FTI should be in the FEC-BB as it is 
>more useful than just for FLUTE (see Toni's comments)
>
>MW: See my response to Toni's comment.

Yep, let's take that on the other thread.

>2a. OK providing FEC-BB preserves all the information 
>specified (to be checked)
>
>MW: That was the intention.

My complete FEC-BB review is nigh...

>3) OK . However there are a couple of issues with FEC-BB...
> 
>- FEC-BB §9.1 references the experimental FLUTE. Please remove 
>this reference or change to a note "to be removed by the RFC editor"
>
>MW: It's just an informative reference to indicate that the 
>algorithm is identical to the one previously specified in the 
>Experimental RFC. Is this a problem ? We can remove it if you like.

Yep, this mustn't go into the standards track FEC-BB RFC. It's good as a note to be removed until all FLUTE, ALC, LCT, FEC-BB, FEC-basic are re-aligned

>- The improved (FEC-BB) wording doesn't take into account the 
>improved integer version Vincent, Jani & Sami produced. 
>(though it does remove the important note that the alg does 
>not imply floating point arithmetic). This was all put in 
>because of actual implementation experience and bugs so the 
>integer stuff really does need mentioning. I guess using the 
>integer algorithm (with improved wording if possible) is the 
>best solution. 
> 
>MW: There isn't any non-integer arithmetic in the algorithm 
>specified in the new FEC BB. The problem with the previous 
>algorithm was that it had an actual real-valued variable 
>'A_fraction' which was the multiplied by some integer and thus 
>the integer implementation of this was not so clear. But this 
>is removed now.

I take another look and bring it up again only if there need for something different.

>Can you point me at the other description that you refer to so 
>I can better understand the difference ?

http://www.watersprings.org/pub/id/draft-peltotalo-rmt-bb-fec-supp-xor-pcm-rs-00.txt

>4) OK - but this relates to the definition of EXT_FTI. I think 
>it should say in each instance "semantically equivalent to X 
>as defined in the FEC-BB [REF]". Though I need to check that 
>the FEC-BB does properly define these in this context...
>
>MW: Nothing to do with EXT-FTI, just the FDT. But yes, it 
>should refer to the FEC BB just as you suggest. The FEC BB 
>should indeed properly define these things and the FEC Schemes 
>define the value ranges.

EXP FLUTE says "field X of FDT is sementically equivalent to field Y of EXT_FTI" in a number of places. This link needs preserving even though specific mention of FEC ID numbers can be pushed elsewhere (FEC-BB or FEC-basic, etc.).


Cheers, Rod.