Re: [rtcweb] Sending of zero-length messages over data channels

[Justin Uberti <[e-mail]>]

On Thu, Jul 24, 2014 at 2:10 PM, Makaraju, Maridi Raju (Raju) <
[e-mail]> wrote:

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> Changing the send() API defeats the purpose of trying to provide full
> WebSockets compatibility.
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> *<Raju> I understand the desire to make the API compatible to websocket
> API. But, unlike websocket TCP transport, the data channels the underlying
> transport (SCTP) has the flexibility for PPID, which can be utilized to
> achieve the same goal, with the added advantage of using the same approach
> for other use cases (like OOB data delivery). *
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> *IHMO, PPID_EMPTY approach is not straight forward either as at SCTP level
> you still have to send some dummy data (unless SCTP is enhanced) of some
> size (=1 or implementation dependent?), which is not obvious to the user.
> Will the ‘bufferedAmount’ be increased appropriately with the dummy data
> sent? Even if it is accounted for, the application has to know this and be
> mindful of the “mysterious” increase (1 byte or n bytes?) in
> ‘bufferedAmount’, something very unique to SCTP.*
>

We will send 1 byte, and this will not be reflected in bufferedAmount, same
as WebSockets.

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> *PPID_OOB approach is transparent to the user as user sends the data, so
> it is automatically accounted in ‘bufferedAmount’.*
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> *</Raju>*
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> I think the PPID_EMPTY approach (probably PPID_EMPTY_TEXT and
> PPID_EMPTY_BINARY, to be precise) is a simple and complete solution.
>