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RE: [Technical Errata Reported] RFC5458 (1746)



The definition using the undefined term is "TS: Transport Stream
[ISO-MPEG2]."   A method of 
transmission at the MPEG-2 layer using TS Packets; it represents Layer 2
of 
the ISO/OSI reference model.  See also TS Logical Channel and TS
Multiplex."

Fixing this error by defining the term "TS logical channel' is indeed
difficult, but as it was only introduces as one of two 'see also'
references, fixing the definition by deletion seems appropriate as the
'see also' only misleads. 
So, I suggest the last sentence be changed to read "See also TS
Multiplex."

This would remove the reference to an undefined term, and thereby
resolve the documentation issue.

Art
Art Allison

Senior Director Advanced Engineering, Science and Technology
 
National Association of Broadcasters
1771 N Street NW
Washington, DC 20036
Phone  202 429 5418 
Fax  202 775 4981
www.nab.org

Advocacy  Education  Innovation




|-----Original Message-----
|From: owner-ipdvb@erg.abdn.ac.uk 
|[mailto:owner-ipdvb@erg.abdn.ac.uk] On Behalf Of Gorry Fairhurst
|Sent: Wednesday, April 29, 2009 2:46 AM
|To: ipdvb@erg.abdn.ac.uk
|Cc: rfc-editor@rfc-editor.org; p.pillai@Bradford.ac.uk; 
|mnoist@cosy.sbg.ac.at; sunil.iyengar@logica.com; 
|rdroms@cisco.com; jari.arkko@piuha.net; ah@TR-Sys.de
|Subject: Re: [Technical Errata Reported] RFC5458 (1746)
|
|After looking at this reported Errata, I suggest there does 
|seems to be a valid issue to note. My thoughts are that the 
|term 'TS logical channel' has been used to describe a 
|component of the TS multiplex, carried as an elementary stream 
|(ES) over a MPEG-2 TS. This term was used to differentiate it 
|from the term "stream" which is widely used in other IETF 
|specs to describe something different. It is not a peer of 'TS 
|multiplex'.
|
|Given the term is already defined in other RFCs that are 
|cited, I suggest this is not likely to result in 
|implementation errors in future protocols.  I suggest the WG 
|categorise this as "Hold for Document Update" - i.e. a future 
|update of the document should consider this erratum when 
|making the update.
|
|If anyone would like to add further comments, please send them 
|to the list by 5th May 2009. After this date we will inform 
|the RFC-Ed of a decision.
|
|Best wishes,
|
|Gorry Fairhurst
|IPDVB Chair
|
|Allison, Art wrote:
|> It is simply dead wrong to use TS logical channel in relation to 
|> defining a Transport Stream.
|> The errata should delete the term TS logical  channel, not define it 
|> as it only misleads and propagates misunderstanding.
|> 
|> The term 'TS logical channel'  is not a peer of 'TS 
|multiplex', it is 
|> a component of the TS multiplex.
|> 
|> A MPEG-2 Transport Stream is a multiplex consisting of a 
|collection of 
|> elementary streams in 188-byte packets each stream having a Packet 
|> IDentifier (PID).
|> 
|> I attempted to inform authors of RFC4326 of the poor construction at 
|> the time, but the inventors of the term had more time and 
|used it very 
|> very narrowly so it was no longer dead wrong use, at which point my 
|> budget to support this work was exhausted.
|>  
|> I do have time to educate and advocate better resolution of this 
|> errata; but for accurate usage of PID and transport stream 
|see ISO/ITU 
|> 13818-1, not later attempts to 'clarify' those terms by those not 
|> expert in
|> MPEG-2 Systems. 
|> 
|> Art
|> Art Allison
|> 
|> Director Advanced Engineering, Science and Technology
|>  
|> National Association of Broadcasters
|> 1771 N Street NW
|> Washington, DC 20036
|> Phone  202 429 5418
|> Fax  202 775 4981
|> www.nab.org
|> 
|> Advocacy  Education  Innovation
|> 
|> 
|>   
|> 
|> 
|> 
|> |-----Original Message-----
|> |From: owner-ipdvb@erg.abdn.ac.uk
|> |[mailto:owner-ipdvb@erg.abdn.ac.uk] On Behalf Of 
|> |H.Cruickshank@surrey.ac.uk
|> |Sent: Tuesday, April 07, 2009 11:47 AM
|> |To: rfc-editor@rfc-editor.org; p.pillai@Bradford.ac.uk; 
|> |mnoist@cosy.sbg.ac.at; sunil.iyengar@logica.com; rdroms@cisco.com; 
|> |jari.arkko@piuha.net; townsley@cisco.com; gorry@erg.abdn.ac.uk
|> |Cc: ah@TR-Sys.de; ipdvb@erg.abdn.ac.uk
|> |Subject: RE: [Technical Errata Reported] RFC5458 (1746)
|> |
|> |
|> | Hi again,
|> |
|> |I suggest to add the the TS Logical Channel definition (taken from 
|> |RFC 4326). So here is the proposed text:
|> |
|> |*********************************************
|> |
|> |TS Logical Channel: Transport Stream Logical Channel. In this 
|> |document, this term identifies a channel at the MPEG-2 level 
|> |[ISO-MPEG2]. It exists at level 2 of the ISO/OSI reference 
|model. All 
|> |packets sent over a TS Logical Channel carry the same PID 
|value (this 
|> |value is unique within a specific TS Multiplex). The term 
|"Stream" is 
|> |defined in MPEG-2 [ISO-MPEG2] to describe the content carried by a 
|> |specific TS Logical Channel (see ULE Stream). Some PID values are 
|> |reserved (by
|> |MPEG-2) for specific signalling. Other standards (e.g., ATSC,
|> |DVB) also reserve specific PID values.
|> |
|> |**********************************************
|> |
|> |
|> |----
|> |Dr. Haitham S. Cruickshank
|> |Lecturer
|> |Communications Centre for Communication Systems Research
|> |(CCSR) BA Building, Room E11 School of Electronics, Computing and 
|> |Mathematics University of Surrey, Guildford, UK, GU2 7XH
|> | 
|> |Tel: +44 1483 686007 (indirect 689844)
|> |Fax: +44 1483 686011
|> |e-mail: H.Cruickshank@surrey.ac.uk
|> |http://www.ee.surrey.ac.uk/Personal/H.Cruickshank/
|> |
|> |-----Original Message-----
|> |From: RFC Errata System [mailto:rfc-editor@rfc-editor.org]
|> |Sent: 30 March 2009 08:25
|> |To: Cruickshank HS Dr (CCSR); p.pillai@bradford.ac.uk; 
|> |mnoist@cosy.sbg.ac.at; sunil.iyengar@logica.com; rdroms@cisco.com; 
|> |jari.arkko@piuha.net; townsley@cisco.com; gorry@erg.abdn.ac.uk
|> |Cc: ah@TR-Sys.de; ipdvb@erg.abdn.ac.uk; rfc-editor@rfc-editor.org
|> |Subject: [Technical Errata Reported] RFC5458 (1746)
|> |
|> |
|> |The following errata report has been submitted for RFC5458, 
|"Security
|> |Requirements for the Unidirectional Lightweight Encapsulation (ULE)
|> |Protocol".
|> |
|> |--------------------------------------
|> |You may review the report below and at:
|> |http://www.rfc-editor.org/errata_search.php?rfc=5458&eid=1746
|> |
|> |--------------------------------------
|> |Type: Technical
|> |Reported by: Alfred Hoenes <ah@TR-Sys.de>
|> |
|> |Section: 2
|> |
|> |Original Text
|> |-------------
|> |[[ at the bottom of page 5 / top of page 6 ]]
|> |
|> |   TS: Transport Stream [ISO-MPEG2].  A method of 
|transmission at the
|> |   MPEG-2 layer using TS Packets; it represents Layer 2 of 
|the ISO/OSI
|> |   reference model.  See also TS Logical Channel and TS Multiplex.
|> |                              ^^^^^^^^^^^^^^^^^^^^^^^
|> |
|> |<< page break >>
|> |
|> |   TS Multiplex: In this document, ...
|> |
|> |
|> |
|> |Corrected Text
|> |--------------
|> |   TS: Transport Stream [ISO-MPEG2].  A method of 
|transmission at the
|> |   MPEG-2 layer using TS Packets; it represents Layer 2 of 
|the ISO/OSI
|> |   reference model.  See also TS Logical Channel and TS Multiplex.
|> ||
|> ||  TS Logical Channel: ...   << to be filled in >>
|> ||  ...
|> |
|> |   TS Multiplex: In this document, ...
|> |
|> |
|> |
|> |
|> |Notes
|> |-----
|> |The quoted keyword explanation for "TS Logical Channel" 
|> |is missing in Section 2.
|> |
|> |Authors/Verifiers:
|> |  Please restore the entry and fill in the missing Corrected Text.
|> |
|> |Instructions:
|> |-------------
|> |This errata is currently posted as "Reported". If 
|necessary, please use
|> |"Reply All" to discuss whether it should be verified or 
|> |rejected. When a
|> |decision is reached, the verifying party (IESG) can log in to 
|> |change the
|> |status and edit the report, if necessary. 
|> |
|> |--------------------------------------
|> |RFC5458 (draft-ietf-ipdvb-sec-req-09)
|> |--------------------------------------
|> |Title               : Security Requirements for the Unidirectional
|> |Lightweight Encapsulation (ULE) Protocol
|> |Publication Date    : March 2009
|> |Author(s)           : H. Cruickshank, P. Pillai, M. Noisternig, S.
|> |Iyengar
|> |Category            : INFORMATIONAL
|> |Source              : IP over DVB
|> |Area                : Internet
|> |Stream              : IETF
|> |Verifying Party     : IESG
|> |
|> |
|> 
|> 
|
|
|