Re: [Technical Errata Reported] RFC5458 (1746)

[Gorry Fairhurst <[e-mail]>]

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  [phone] 
> Fax  [phone]
> www.nab.org
> 
> Advocacy  Education  Innovation
> 
> 
>   
> 
> 
> 
> |-----Original Message-----
> |From: [e-mail] 
> |[mailto:[e-mail]] On Behalf Of 
> |[e-mail]
> |Sent: Tuesday, April 07, 2009 11:47 AM
> |To: [e-mail]; [e-mail]; 
> |[e-mail]; [e-mail]; 
> |[e-mail]; [e-mail]; [e-mail]; 
> |[e-mail]
> |Cc: [e-mail]; [e-mail]
> |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: [phone] (indirect 689844)
> |Fax: [phone]
> |e-mail: [e-mail]
> |http://www.ee.surrey.ac.uk/Personal/H.Cruickshank/ 
> |
> |-----Original Message-----
> |From: RFC Errata System [mailto:[e-mail]]
> |Sent: 30 March 2009 08:25
> |To: Cruickshank HS Dr (CCSR); [e-mail]; 
> |[e-mail]; [e-mail]; 
> |[e-mail]; [e-mail]; [e-mail]; 
> |[e-mail]
> |Cc: [e-mail]; [e-mail]; [e-mail]
> |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 <[e-mail]>
> |
> |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
> |
> |
> 
>