W3C home > Mailing lists > Public > public-webrtc@w3.org > February 2015

Re: Javascript based browser API to send/receive the RTCP APP messages

From: Randell Jesup <randell-ietf@jesup.org>
Date: Wed, 18 Feb 2015 18:24:45 -0500
Message-ID: <54E51F3D.5030406@jesup.org>
To: public-webrtc@w3.org
On 2/18/2015 2:18 PM, Justin Uberti wrote:
> If you use BUNDLE, these disadvantages go away entirely.

I agree.  (Though per below, you need to actually do DTLS instead of 
just using it to key DTLS-SRTP).  As BUNDLE is the way everything is 
heading, even if it uses some extra resources in the meantime that issue 
will disappear soon (likely by the time you deploy in any volume, or 
before).

> Right now there are no plans to support RTCP APP messaging in the 1.0 
> timeframe.

Right.  And I'll re-iterate what I said (which was not "support" for APP 
messages):
"If you need to talk to legacy equipment that requires RTCP APPs, you 
have to be going through a webrtc->legacy gateway anyways, so in the 
gateway translate DataChannel datagrams to RTCP APPs."

Just because an RTP application you're gatewaying to do X doesn't mean 
WebRTC should/will do X...  RTCP APP's are (as I said) a hack to 
implement an unreliable, ugly data channel in legacy RTP applications.

    Randell Jesup

>
> On Mon, Feb 16, 2015 at 8:12 PM, Bibhudatta Biswal 
> <bbibhu@kodiaknetworks.com <mailto:bbibhu@kodiaknetworks.com>> wrote:
>
>     Thanks Randell for the support.
>
>     Implementing DataChannels to support the RTCP APP message has the
>     following disadvantages.
>
>     ·Consumes the additional resource on the operator’s NAT/Firewal to
>     create the separate port/connection mapping.
>
>     ·In the RTCP-MUX scenarios, we need to have the separate DTLS
>     session for the data channel just to send/receive the RTCP APP
>     message which could have been done as SRTCP message on the same
>     RTP port.
>
>     In Push To Talk Over Cellular applications, the Media Burst
>     Control Protocol (MBCP) is used to exchange the floor/volley
>     information which is based on the RTCP Application Packets (RTCP:
>     APP). The MBCP protocol is defined by the Open Mobile
>     Alliance(OMA) group is widely used for Push To Talk over cellular
>     applications.
>
>     Please find the link to the specification below.
>
>     http://technical.openmobilealliance.org/Technical/release_program/docs/PoC/V2_0-20071002-C/OMA-TS-PoC_UserPlane-V2_0-20071002-C.pdf
>
>


-- 
Randell Jesup -- rjesup a t mozilla d o t com
Received on Wednesday, 18 February 2015 23:25:32 UTC

This archive was generated by hypermail 2.3.1 : Monday, 23 October 2017 15:19:43 UTC