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

Tim Panton <> Tue, 15 November 2011 08:32 UTC

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Date: Tue, 15 Nov 2011 08:31:55 +0000
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Subject: Re: [rtcweb] Traffic should be encrypted. (Re: Let's define the purpose of WebRTC)
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On 14 Nov 2011, at 19:12, Michael Thornburgh wrote:

> in "those proprietary plugins" that nobody ever namesFlash, media streams have a generic data channel that is time synchronized to the media. calling the "send" method on a publishing-to-peers-or-server stream puts the current media timestamp on the message. at the subscriber end the callback associated with the message is called synchronized with the playback media clock.
> this is useful for example when recording and playing back the non-media parts of an online meeting, such as text messages or slide changes, or insertion of cue points in media, or text captions, or etc.
> in Those Proprietary Plugins That Must Not Be Named, the data channel of a stream can be fully reliable or partially reliable. the timing semantics for a time-synchronized data message is that it won't trigger its callback before its timestamp, but if it will trigger if it arrives late (which might happen for a fully reliable message).
> -mike

Not all proprietary plugins are Flash ;-) - We have a Java  applet that implements IAX - which ends up 
with similar properties - you can send and receive data (in a few formats although mostly we ended up
putting JSON in text) - the data is reliable, timestamped with the media time,  sequenced datagram (not a stream). Most usages ignore the media timestamp and just process it 'immediately' but on occasion the timestamp is useful.