Re: [rtcweb] Review comments on draft-ietf-rtcweb-data-protocol-03

Paul Kyzivat <> Tue, 04 March 2014 17:56 UTC

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Subject: Re: [rtcweb] Review comments on draft-ietf-rtcweb-data-protocol-03
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On 2/25/14 5:07 PM, Michael Tuexen wrote:

>> 2. Section 4:
>> The method
>>    used to determine which side uses odd or even is based on the
>>    underlying DTLS connection role when used in WebRTC, with the side
>>    acting as the DTLS client using even stream identifiers.
>> Isn't this unnecessary using the vague word of WebRTC instead of simply
>> pointing to the DTLS roles of the established data channel?
> The point is that in the WebRTC you use DCEP/SCTP/DTLS/UDP and therefore
> you can refer to the DTLS role. However, you could use DCEP/SCTP/IP
> or DCEP/SCTP/UDP/IP or DCEP/SCTP over something not involving DTLS.
> In that case DTLS is not used and you can not refer to the DTLS role.
> That is why the restriction is used.

So data channels could work over SCTP/IP or SCTP/UDP/IP, but in fact 
can't solely because the choice of even/odd role is dependent on DTLS 
connection role?

Couldn't you find a way to choose the even/odd role based solely on the 
SCTP layer and the SDP? Then data channels could be used over those 
other stacks.