Re: [rtcweb] Traffic should be encrypted. (Re: Let's define the purpose of WebRTC)

[Randell Jesup <[e-mail]>]

On 11/14/2011 10:47 AM, Neil Stratford wrote:
> On Mon, Nov 14, 2011 at 3:34 PM, Randell Jesup <[e-mail] wrote:
>     Note my other email I just sent - DTMF has a property not shared by
>     the data streams - media synchronization.  I won't repeat all the
>     arguments here, but there actually is a reason for delivering it in
>     a media channel, totally regardless of legacy.  For a greenfield
>     design, one *might* implement it as a separate media stream (m=
>     line), but even there I'm not sure I would mandate it be separated.
>
>
> How can we achieve the media synchronization in WebRTC? In a traditional
> RTC endpoint the DTMF comes from the same source as the media, in many
> cases it's actually taken from the media itself. However in WebRTC the
> only way to trigger a DTMF event is through an asynchronous Javascript
> function call, which is not synchonized to the media. Do we assume that
> the function call happens 'at about the right time' and take that as the
> current timestamp to use?

That speaks to the API needing tweaking - the JS app generally knows 
*when* (in realtime) the event occurred; it should pass that info in 
with the command to send it so the synchronized data can be correctly 
generated (along with the other timing info - duration or ongoing until 
told to stop).  ("When" could also include a special case for "now", 
defined as the current media clock position when the function call is 
processed.)


-- 
Randell Jesup
[e-mail]