Subject: Re: WG LAST CALL: I-D ACTION:draft-ietf-ipvbi-nabts-00.txt

From: jimcarr <[email-masked]>
Date: Tue, 17 Nov 1998 13:59:29 -0500

Dan:

I have a number or rather mundane minor changes I would like to suggest 
which most will find quite boring I am sure..... they are:

1. The Table of Contents needs the pages to be renumbered and the last
two section numbers do not follow .. they should be 13 and 14.

2. The last paragraph of Page 1, second line, should include references as 
follows: "....(NABTS), REF. [2]...."

3. The last paragraph of Page 1, line 10 should read: "....NABTS, (REF. [5] & [6])..."

4. Section 5.1 should refer to 525 and 635 line systems, not the colour
encoding method and the US is not the only country using 525 lines. Suggest 
Section 5.1.1 read as follows:

"5.1.1. 525 line systems

An 525 television frame is comprised of 2 fields of 262.5 horizontal 
scan lines each.  The first 21 lines of each field are not part of the 
visible picture and are collectively called the Vertical Blanking 
Interval (VBI).  Of these 21 lines the first 9 are used while 
repositioning the cathode ray to the top of the screen, but the 
remaining lines are available for data transport.

There are 12 possible VBI lines being broadcast 60 times a second (each
field 30 times a second). In some countries Line 21 is reserved for the 
transport of closed captioning data (Ref.[10]).  In that case there are 
11 possible VBI lines, some or all of which could be used for multicast 
IP transport.  It should be noted that some of these lines are sometimes 
used for existing, proprietary, data and testing services.  Multicast 
IP therefore becomes one more data service using a subset or all of 
these lines.

5. Section 5.1 VBI has a sub-section 5.1.2 is missing. It should read
something like:

"5.1.2 625 Line Systems

A 625-line television frame is comprised of 2 fields of 312.5 horizontal
scan lines each.  The first few lines of each field are used while
repositioning the cathode ray to the top of the screen.  The lines
available for data insertion are 6-22 in the first field and 319-335 in
the second field.

There are therefore 17 possible VBI lines being broadcast 50 times a
second (each field 25 times a second), some or all of which could be
used for multicast IP transport.  It should be noted that some of these
lines are sometimes used for existing, proprietary, data and testing
services.  Multicast IP therefore becomes one more data service using a
subset or all of these lines."

6. Section 5.2, first paragraph, should read "... Electronic Industry
Association's EIA-516 and ITU.R BT.653-2, system C".

7. Page 4 (a typical example) refers to "Packet Group address" but in
NABTS the terminology used is "Packet Address".

8. Page 4, third paragraph, 7th line should read: ".....length of the
suffix of the...."

9. Page 4, third paragraph, the addition of a small table might make 
this clearer. A suggestion is:

TYPE OF PACKET                  PS
-------------------------------------------
Data Packet, no filler            D0
Data Packet, with filler          8C
FEC Packet                        A1

10. Last paragraph of Section 5.3, 2nd line should read: "If single bit
errors, double bit errors, single byte errors or single and double byte
erasures are found ...."

I hope this is of assistance.

Cheers
Jim Carruthers

----------------

[email-masked] wrote:
> 
> I am issuing a working group last call for our IP over NABTS
> Internet-Draft.  This means that my understanding is that we've achieved
> consensus on the IP over NABTS issues and are ready to forward the draft
> to the IESG to be considered as a standards-track RFC.  If people within
> the working group have any objections to the draft as it stands, they
> should be raised now.
> 
> I think a two-week review period should be sufficient, so this last call
> will end on Wednesday, November 18th.  Please read the draft carefully
> if you have not already done so and forward any concerns to the list.
> 
> Our last substantive discussion on the list revolved around the issue of
> how to divide the previous draft: the consensus at the face to face
> meeting was to divide into a NABTS draft and a WST draft, but some
> argued for a 525 draft and a 625 draft.  I only draw attention to this
> because my own view was that there were no compelling reasons to switch
> from the NABTS/WST split to the 525/625 split, but if anyone still feels
> they can make a strong case they should do so now so we can make a final
> decision and move on.
> 
> Thanks to everyone who has participated so far, and I look forward to
> reading your comments during this final review.  Then we can dive right
> in to the WST draft.
> 
>         Dan
> 
> ---------------------------------------------------
> Dan Zigmond
> Co-Manager, Interactive Television
> Senior Manager, Interactive Television Standards
> WebTV Networks, Inc.
> [email-masked]
> ---------------------------------------------------
> 
> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]]
> On Behalf Of [email-masked]
> Sent: Friday, October 23, 1998 7:21 AM
> To: IETF-Announce: ;
> Cc: [email-masked]
> Subject: I-D ACTION:draft-ietf-ipvbi-nabts-00.txt
> 
> A New Internet-Draft is available from the on-line Internet-Drafts
> directories.
> This draft is a work item of the IP over VBI Working Group of the IETF.
> 
>         Title           : THE TRANSMISSION OF IP OVER THE VERTICAL BLANKING
>                           INTERVAL OF A TELEVISION SIGNAL
>         Author(s)       : R. Panabaker, S. Wegerif, D. Zigmond
>         Filename        : draft-ietf-ipvbi-nabts-00.txt
>         Pages           : 21
>         Date            : 22-Oct-98
> 
> This is an Internet-Draft, which describes a method for broadcasting
> multicast IP data using the vertical blanking interval of television
> signals.  It includes a description for compressing multicast IP headers
> on unidirectional networks, a framing protocol identical to SLIP, a
> forward error correction scheme, and the NABTS byte structures.
> 
> Keywords: VBI, broadcast, push, FEC, television, NABTS, IP, multicast.
> 
> Internet-Drafts are available by anonymous FTP.  Login with the username
> "anonymous" and a password of your e-mail address.  After logging in,
> type "cd internet-drafts" and then
>         "get draft-ietf-ipvbi-nabts-00.txt".
> A URL for the Internet-Draft is:
> ftp://ftp.ietf.org/internet-drafts/draft-ietf-ipvbi-nabts-00.txt
> 
> Internet-Drafts directories are located at:
> 
>         Africa: ftp.is.co.za
> 
>         Europe: ftp.nordu.net
>                 ftp.nis.garr.it
> 
>         Pacific Rim: munnari.oz.au
> 
>         US East Coast: ftp.ietf.org
> 
>         US West Coast: ftp.isi.edu
> 
> Internet-Drafts are also available by mail.
> 
> Send a message to:      [email-masked].  In the body type:
>         "FILE /internet-drafts/draft-ietf-ipvbi-nabts-00.txt".
> 
> NOTE:   The mail server at ietf.org can return the document in
>         MIME-encoded form by using the "mpack" utility.  To use this
>         feature, insert the command "ENCODING mime" before the "FILE"
>         command.  To decode the response(s), you will need "munpack" or
>         a MIME-compliant mail reader.  Different MIME-compliant mail readers
>         exhibit different behavior, especially when dealing with
>         "multipart" MIME messages (i.e. documents which have been split
>         up into multiple messages), so check your local documentation on
>         how to manipulate these messages.
> 
> Below is the data which will enable a MIME compliant mail reader
> implementation to automatically retrieve the ASCII version of the
> Internet-Draft.

---

From: jimcarr <[email-masked]>
Date: Tue, 17 Nov 1998 14:02:17 -0500

some small corrections to my small corrections .... Jim

Dan:

I have a number of rather mundane minor changes I would like to suggest 
which most will find quite boring I am sure..... they are:

4. Section 5.1 should refer to 525 and 625 line systems, not the colour
encoding method and the US is not the only country using 525 lines. Suggest 
Section 5.1.1 read as follows:

"5.1.1. 525 line systems

"5.1.2 625 Line Systems

TYPE OF PACKET                  PS

Cheers
Jim Carruthers

----------------