Re: [Ice] I submitted and plan to present draft-thatcher-ice-remove-candidate in Berlin

[Christer Holmberg <[e-mail]>]

Hi,

>> The text says:
>> 
>>       “The Receiving Agent MAY keep the existing candidate pairs that use
>>         the Removed Candidates and behave as though the Removed Candidates
>>         had not been removed for those candidate pairs.”
>> 
>> What is meant by “behave”? Sending keep-alives? Sending media? That will obviously not work.
>
​> Both keep-alives and media.  If the removed candidate is a TURN candidate that the removing agent wishes to deallocate, it may work for a short period 
> of time before the removing agent actually > deallocates it.  So the Receiving Agent may choose to keep sending media until it finds a different candidate pair to use instead.   
> Or it may not.  
 
The removed candidate MAY work for a short period, but there is no guarantee, is there? So, if the receiver understands the mechanism, shouldn't it switch to another candidate as soon as it receives the indication that the candidate has been removed (if the removed candidate is the one currently being used, that is).
 

>> I think it would be good to state whether the usage/support of the mechanism must be negotiated before it is used.
​>
​> Signaling the removal of candidate never does any harm, so I don't see a need in negotiating that your going to signal removal (modulo a specific signaling protocol needing to figure out how to send 
> new messages if it chooses to do so).  The real question is whether the removing agent needs to know whether the receiving agent is going to do anything with the signal.  And since everything will 
> continue to work even if the receiving ​agent ignores the signal (simply with some perhaps wasted resources), then it's not necessary for negotiation at all.

If the removed candidate cannot be used once it has been removed, and the remote endpoint keep sending media towards it (e.g. because the remote endpoint does not understand the removal indication), there will be media clipping until the remote endpoint realizes that the candidate no longer works.

Regards,

Christer

 
 
 
From: Ice [mailto:[e-mail]] On Behalf Of Peter Thatcher
Sent: 12 July 2016 17:35
To: [e-mail]
Subject: [Ice] I submitted and plan to present draft-thatcher-ice-remove-candidate in Berlin
 
I submitted draft-thatcher-ice-remove-candidate and would like to speak about in my allotted time on the agenda when I will also be speaking about draft-thatcher-ice-network-cost and draft-thatcher-ice-renomination.
 
It's a very simple draft. Basically it says you can "remove" candidates just like trickle-ice allows you to add candidates. You could probably read it in 3 minutes. Please do so:
 
https://www.ietf.org/id/draft-thatcher-ice-remove-candidate-00.txt 
 
Thanks,
Peter (Chair hat off)