[rtcweb] Mode 1 and getUserMedia

[James Pearce <[e-mail]>]

Hi,

I have a quesion about the use of getUserMedia to obtain user consent for
Mode 1 operation.

I have an application that uses WebRTC to deliver real-time media streams
in one direction only. Client applications are consumers only, in some
cases the client devices do not have any media capture capability.
I'm trying to develop a strategy for deploying the application on the
public web so, naturally, my plan is to use TURN to relay through NAT.

I've run into trouble with
  a) The requirement that Mode 1 is needed to use TURN
  b) User consent for Mode 1 is tied to getUserMedia()

Firstly, it's not clear to me why there is a restriction on using TURN in
mode 2. Does TURN reveal address information that would otherwise be hidden
to the peer? I've noticed that Chrome seems to use TURN even without
consent being given. Firefox does not.

Secondly, with no capture devices, getUserMedia can never succeed, thus, a
user can never give consent for Mode 1. This is unfortunate, as WebRTC is
ideal for some applications that require one-way streaming to limited-spec
devices. Granted, not many devices today have no capture capability, but
even when they do, requesting permission to access a microphone when it'll
never be needed is confusing to end users. Is there a better mechanism we
can use to obtain consent when getUserMedia is not necessary?


I know I've raised this issue tangentially before, but having to explain
issues to end users is beginning to wear thin. It's becoming a headache.

Thanks,

James