Re: [MMUSIC] MSRP data channel and CEMA

Paul Kyzivat <pkyzivat@alum.mit.edu> Wed, 14 August 2019 20:05 UTC

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From: Paul Kyzivat <pkyzivat@alum.mit.edu>
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Subject: Re: [MMUSIC] MSRP data channel and CEMA
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On 8/14/19 1:34 PM, Christer Holmberg wrote:
> Hi,
> 
>>> I was thinking more about CEMA and MSRP data channels.
>>>   
>>> RFC 6714 says:
>>>   
>>>     “MSRP endpoints that support the CEMA extension will use the SDP c/m-line address
>>>     information for establishing the TCP or TLS connection for sending
>>>     and receiving MSRP messages.”
>>>   
>>> …which is exactly what is done when a data channel is established.
>>>
>>> Of course, the data channel will be established using the c/m- line no matter whether
>>> CEMA is indicated or not, but I think it would be good to have it explicit.
>>
>> Thinking about it, I think one possible approach to make it more clear could be: 1) mandate that endpoints include the CEMA attribute , and
>>
>> 2) specify that transport level gateways should not forward CEMA attributes from/to data channel endpoints.
> 
> Why would they not forward the CEMA attribute?

ISTM that a separate decision would be made about the need for CEMA on 
the next hop.

	Thanks,
	Paul