Re: [rtcweb] Data channel comments and questions

<> Thu, 29 March 2012 20:36 UTC

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Eric Rescorla [] wrote:
>> 3. HTTP tunneling: In practice we are going to need HTTP tunneling last-
>resort option for the data channel as well. If doing so, what will the protocol
>stack look like? Is it SCTP/DTLS/UDP/HTTP/TLS/TCP? Or can we collapse some
>of these layers. I think we'd better.
>I don't think I understand point 3. Why would we need HTTP tunneling?
>If we can bring
>up a bidirectional UDP channel, then why would we need to run HTTP over it?

Ah, sorry for not being clear. I mean a situation where we can't setup the UDP channel, if one endpoint is for instance in a corporate network from where only HTTP or HTTPS is allowed. So presumably we'd have to support some kind of HTTP or TLS encapsulation/tunneling for the data channel as well, from the endpoint to some kind of relay. But how would the end-to-end data channel look like then? I.e. what would be sent over the tunnel?