Re: [MMUSIC] RID, MID and BUNDLE: Associate received RTP packet with m- line

Adam Roach <adam@nostrum.com> Thu, 22 October 2015 19:22 UTC

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To: Christer Holmberg <christer.holmberg@ericsson.com>, "Mo Zanaty (mzanaty)" <mzanaty@cisco.com>, "mmusic@ietf.org" <mmusic@ietf.org>
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From: Adam Roach <adam@nostrum.com>
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Date: Thu, 22 Oct 2015 14:21:57 -0500
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Subject: Re: [MMUSIC] RID, MID and BUNDLE: Associate received RTP packet with m- line
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On 10/22/15 2:18 PM, Christer Holmberg wrote:
>
> Hi,
>
> >RID (like MID and all SDES items) is limited to 255 octets. No risk of 
> exhaustion, so offerers are free to make them >unique across the whole 
> SDP if they want.
>
> If there is no risk of exhaustion, is there a reason not to MANDATE 
> them to be unique?
>

Well, it's an unnecessary restriction, and we'd like people to keep them 
short. While they won't be in every packet, they'll likely be in the 
*same* packets as other correlating identifiers like MID (e.g., at 
stream startup).

On the balance, it's not much of a trade-off. The size of these things 
can still be pretty small if they're unique, but being unique buys you 
(almost?) nothing.

/a