Linda, thanks for your review. Christer, Gunnar, thanks for your responses. I 
entered a No Objection ballot.

Alissa


> On Feb 15, 2020, at 5:33 AM, Gunnar Hellström <[email protected]> 
> wrote:
> 
> Hi Linda,
> I get the impression that you did think of T.140 as a standardized 
> combination of audio, video and real-time text. That combination is called 
> "total conversation", a term first mentioned in ITU-T F.703 "Multimedia 
> conversational services", and after that mentioned in various standards for 
> various technical environments. 
> 
> T.140 can be thought of as a "text codec" for the real-time text media. It 
> can be combined with an audio codec and a video codec, all with their 
> specific but externally specified packetization and transport standards for 
> each technical session environment. WebRTC is one, where audio and video are 
> carried by SRTP and T.140 real-time text by the WebRTC data channel in the 
> way specified by the t140-usage draft. 
> 
> A session can contain any combination of these three media, as well as other 
> data channel types.
> 
> Regards
> 
> Gunnar
> 
> Den 2020-02-14 kl. 23:16, skrev Christer Holmberg:
>> Hi,
>>  
>> >Yes, that is exactly what I was asking.
>> > 
>> >Based on your answer, the second sentence of your page 2 should be:
>> > 
>> >“ this document specifies how a WebRTC data channel is used as a transport 
>> >for
>> > the real time text of T140”.
>> 
>> It is the "of T140" part that confuses me. 
>> 
>> T140 is ONLY for real-time text. There is no "T140 audio" or "T140 video".
>> 
>> Regards,
>> 
>> Christer
>>  
>>  
>> Linda
>>  
>> From: Christer Holmberg <[email protected]> 
>> <mailto:[email protected]> 
>> Sent: Friday, February 14, 2020 4:02 PM
>> To: Linda Dunbar <[email protected]> 
>> <mailto:[email protected]>; Gunnar Hellström 
>> <[email protected]> <mailto:[email protected]>; 
>> [email protected] <mailto:[email protected]>
>> Cc: [email protected] <mailto:[email protected]>; [email protected] 
>> <mailto:[email protected]>; 
>> [email protected] 
>> <mailto:[email protected]>
>> Subject: Re: [MMUSIC] Genart last call review of 
>> draft-ietf-mmusic-t140-usage-data-channel-11
>>  
>> Hi Linda,
>>  
>> >Gunnar, 
>> 
>> I am not Gunnar, but I will reply :)
>> 
>> >Thank you very much for the explanation. 
>> >
>> >Do you mean WebRTC data channel is used as Transport mechanism for 
>> >real-time text, >but Audio and Video of T140  still use RTP or SRTP? 
>>  
>> I am not sure what you mean by "Audio and Video of T140". In WebRTC Audio 
>> and Video use SRTP, while the T.140 real-time text uses the data channel.
>>  
>> Regards,
>>  
>> Christer
>> 
>> 
>> -----Original Message-----
>> From: Gunnar Hellström <[email protected] 
>> <mailto:[email protected]>> 
>> Sent: Friday, February 14, 2020 1:03 PM
>> To: Linda Dunbar <[email protected] 
>> <mailto:[email protected]>>; [email protected] 
>> <mailto:[email protected]>
>> Cc: [email protected] <mailto:[email protected]>; [email protected] 
>> <mailto:[email protected]>; 
>> [email protected] 
>> <mailto:[email protected]>
>> Subject: Re: [MMUSIC] Genart last call review of 
>> draft-ietf-mmusic-t140-usage-data-channel-11
>> 
>> Hi Linda,
>> 
>> You ask below:
>> "ITU-T T.140 uses RTP as transport, whereas this document describes using 
>> WebRTC for transport. WebRTC uses SRTP.
>> 
>> Does it mean this document proposes a different transport mechanism as the 
>> ITU-T T140? Why?"
>> 
>> ITU-T T.140 is a generally applicable presentation protocol for real-time 
>> text. Transports have been standardized for T.140 in a number of multimedia 
>> systems, most of them nowadays obsolete. E.g. ITU-T Q.224 for transport in 
>> H.320 ISDN Multimedia system, ITU-T V.18 for transport by low bitrate 
>> modems. etc. For use in traditional IP based multimedia systems ITU-T H.323 
>> and IETF SIP, RTP transport is the standardized transport with packetization 
>> of T.140 specified in RFC 4103.
>> 
>> When WewbRTC was specified it was early said that only audio and video would 
>> be transported by RTP. All other, including real-time text would use data 
>> channels.  This decision was documented in use case U-C-5 in 
>> ietf-rtcweb-data-channel.
>> 
>> The reviewed draft obeys that decision and specifies how the general
>> T.140 transport is to be applied on a WebRTC data channel.
>> 
>> Regards
>> 
>> Gunnar
>> 
>> 
>> Den 2020-02-14 kl. 17:50, skrev Linda Dunbar via Datatracker:
>> > Reviewer: Linda Dunbar
>> > Review result: Ready with Nits
>> >
>> > I am the assigned Gen-ART reviewer for this draft. The General Area 
>> > Review Team (Gen-ART) reviews all IETF documents being processed by 
>> > the IESG for the IETF Chair.  Please treat these comments just like 
>> > any other last call comments.
>> >
>> > For more information, please see the FAQ at
>> >
>> > <https://protect2.fireeye..com/v1/url?k=7e8050ab-220a727d-7e801030-0cc47ad93dcc-e1706ed98975c910&q=1&e=4dbf2e13-f320-470a-a001-dcb3aa68c975&u=https%3A%2F%2Fnam03.safelinks.protection.outlook.com%2F%3Furl%3Dhttps%253A%252F%252Ftrac...ietf.org%252Ftrac%252Fgen%252Fwiki%252FGenArtfaq%26amp%3Bdata%3D02%257C01%257Clinda.dunbar%2540futurewei.com%257C0c2dca83131747ea654c08d7b18089ee%257C0fee8ff2a3b240189c753a1d5591fedc%257C1%257C0%257C637173037946430564%26amp%3Bsdata%3D3V7hrGs6kgkropYOVPNYC87NczEVIYMDzUQO1DsuXZQ%253D%26amp%3Breserved%3D0
>> >  
>> > <https://nam03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fprotect2.fireeye.com%2Fv1%2Furl%3Fk%3D7e8050ab-220a727d-7e801030-0cc47ad93dcc-e1706ed98975c910%26q%3D1%26e%3D4dbf2e13-f320-470a-a001-dcb3aa68c975%26u%3Dhttps%253A%252F%252Fnam03.safelinks.protection.outlook.com%252F%253Furl%253Dhttps%25253A%25252F%25252Ftrac..ietf.org%25252Ftrac%25252Fgen%25252Fwiki%25252FGenArtfaq%2526amp%253Bdata%253D02%25257C01%25257Clinda.dunbar%252540futurewei.com%25257C0c2dca83131747ea654c08d7b18089ee%25257C0fee8ff2a3b240189c753a1d5591fedc%25257C1%25257C0%25257C637173037946430564%2526amp%253Bsdata%253D3V7hrGs6kgkropYOVPNYC87NczEVIYMDzUQO1DsuXZQ%25253D%2526amp%253Breserved%253D0&data=02%7C01%7Clinda.dunbar%40futurewei.com%7C6db1631dd95d40bbf91d08d7b199866d%7C0fee8ff2a3b240189c753a1d5591fedc%7C1%7C0%7C637173145264409173&sdata=1z2J63ztJbPNdN87ZLiL%2F2I8dgsAMOUQ%2FXf77lh6hnQ%3D&reserved=0>>.
>> >
>> > Document: draft-ietf-mmusic-t140-usage-data-channel-11
>> > Reviewer: Linda Dunbar
>> > Review Date: 2020-02-14
>> > IETF LC End Date: 2020-02-06
>> > IESG Telechat date: Not scheduled for a telechat
>> >
>> > Summary:
>> >   This document specifies how a WebRTC data channel can be used as a 
>> > transport
>> >   mechanism for T.140.  The document  ties several other documents 
>> > together,
>> >   like xxx can be used, yyy must  be followed, etc..  So it is not easy to
>> >   validate the mechanism described by the document unless you are familiar 
>> > with
>> >   all the reference documents.
>> > But in general, the document is very clear.
>> >
>> > Just one question:
>> > ITU-T T.140 uses RTP as transport, whereas this document describes 
>> > using WebRTC for transport.  WebRTC uses SRTP.
>> >
>> > Does it mean this document proposes a different transport mechanism as 
>> > the ITU-T T140?  Why?
>> >
>> > Major issues: None
>> >
>> > Minor issues: None
>> >
>> > Nits/editorial comments:
>> >
>> > Linda Dunbar
>> >
>> > _______________________________________________
>> > mmusic mailing list
>> > [email protected] <mailto:[email protected]>
>> > https://protect2.fireeye.com/v1/url?k=f7978fa8-ab1dad7e-f797cf33-0cc47ad93dcc-963180ddabb9ff10&q=1&e=4dbf2e13-f320-470a-a001-dcb3aa68c975&u=https%3A%2F%2Fnam03.safelinks.protection.outlook.com%2F%3Furl%3Dhttps%253A%252F%252Fwww
>> >  
>> > <https://nam03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fprotect2.fireeye.com%2Fv1%2Furl%3Fk%3Df7978fa8-ab1dad7e-f797cf33-0cc47ad93dcc-963180ddabb9ff10%26q%3D1%26e%3D4dbf2e13-f320-470a-a001-dcb3aa68c975%26u%3Dhttps%253A%252F%252Fnam03.safelinks.protection.outlook.com%252F%253Furl%253Dhttps%25253A%25252F%25252Fwww&data=02%7C01%7Clinda.dunbar%40futurewei.com%7C6db1631dd95d40bbf91d08d7b199866d%7C0fee8ff2a3b240189c753a1d5591fedc%7C1%7C0%7C637173145264419165&sdata=O9apIRsY3I1QWzL5lwwiTumPN60yEZGaxg7ggYsz%2FEA%3D&reserved=0>.
>> > ietf.org 
>> > <http://ietf.org/>%2Fmailman%2Flistinfo%2Fmmusic&amp;data=02%7C01%7Clinda.dunbar
>> > %40futurewei.com 
>> > <http://40futurewei.com/>%7C0c2dca83131747ea654c08d7b18089ee%7C0fee8ff2a3b24018
>> > 9c753a1d5591fedc%7C1%7C0%7C637173037946430564&amp;sdata=hrfRcMoBuD%2BH
>> > fqoYmBbjHuYbO829I1eCTpc1tXogeo0%3D&amp;reserved=0
>> 
>> -- 
>> 
>> + + + + + + + + + + + + + +
>> 
>> Gunnar Hellström
>> Omnitor
>> [email protected] <mailto:[email protected]>
>> +46 708 204 288
>> 
>> _______________________________________________
>> Gen-art mailing list
>> [email protected] <mailto:[email protected]>
>> https://protect2.fireeye.com/v1/url?k=53d6f693-0f5cd445-53d6b608-0cc47ad93dcc-4707848f68d9894a&q=1&e=4dbf2e13-f320-470a-a001-dcb3aa68c975&u=https%3A%2F%2Fwww.ietf.org%2Fmailman%2Flistinfo%2Fgen-art
>>  
>> <https://nam03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fprotect2.fireeye.com%2Fv1%2Furl%3Fk%3D53d6f693-0f5cd445-53d6b608-0cc47ad93dcc-4707848f68d9894a%26q%3D1%26e%3D4dbf2e13-f320-470a-a001-dcb3aa68c975%26u%3Dhttps%253A%252F%252Fwww.ietf.org%252Fmailman%252Flistinfo%252Fgen-art&data=02%7C01%7Clinda.dunbar%40futurewei.com%7C6db1631dd95d40bbf91d08d7b199866d%7C0fee8ff2a3b240189c753a1d5591fedc%7C1%7C0%7C637173145264419165&sdata=vOapG1QkRs%2Bj7bv921OeiEsV1Yu%2FvwelO9RA9yFqhlY%3D&reserved=0>--
>>  
> 
> + + + + + + + + + + + + + + 
> 
> Gunnar Hellström
> Omnitor
> [email protected] <mailto:[email protected]>
> +46 708 204 288
> _______________________________________________
> Gen-art mailing list
> [email protected] <mailto:[email protected]>
> https://www.ietf.org/mailman/listinfo/gen-art 
> <https://www.ietf.org/mailman/listinfo/gen-art>

_______________________________________________
Gen-art mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/gen-art

Reply via email to