Subject: Re: [Ice] WGLC for draft-ietf-ice-rfc5245bis-12 - How to select a candidate pair

From: Christer Holmberg <[email-masked]>
Date: Fri, 6 Oct 2017 10:15:54 +0000

Hi ICE lovers,

Every now and then there has been discussions on what the difference between "nominated candidate pair" and “selected candidate pair" it, who selects etc.

The draft currently contains the following definition for selected pair:

   "Selected Pair, Selected Candidate Pair:  The candidate pair selected
         by an ICE agent for sending media.  Each of its candidates is
         called the selected candidate.  Before a pair has been selected,
         any valid candidate pair can be used for sending and receiving
         media."
That definition looks ok to me. However, what is unclear is exactly how the selection is done.

The draft contains e.g., following wording:

"selected by ICE” - it is unclear what this means.

"If the peer is a full agent, the lite agent selects a candidate pair when the full agent nominates it.” - this make it sound like the controlled agent does the selection.

My suggestion for the definition of how the selection is done:

“Once the controlling agent has nominated a candidate pair, and the controlled agent has accepted the nomination (by sending a successful response to the
binding request with the USE-CANDIDATE attribute) the candidate pair becomes the selected candidate pair.”

In addition, the draft (especially section 5.1.4.2) uses ‘select candidate’ wording with another meaning, which is confusing, so we may want to change to something else. Peter’s PR did such changes, but we may need more.

Regards,

Christer

From: Ice <[email-masked]<mailto:[email-masked]>> on behalf of "[email-masked]<mailto:[email-masked]>" <[email-masked]<mailto:[email-masked]>>
Date: Sunday 1 October 2017 at 09:02
To: "[email-masked]<mailto:[email-masked]>" <[email-masked]<mailto:[email-masked]>>
Subject: [Ice] WGLC for draft-ietf-ice-rfc5245bis-12

(in case you ignore the last once because of the erroneous title)

We are starting a 3-week Working Group Last Call for ICE bis:

https://tools.ietf.org/html/draft-ietf-ice-rfc5245bis-12

 Please review the draft and provide any comments you may have on the document by Oct 21, 2017.

Comments should be sent to the document authors and to the ICE WG list. If you review the document but do not have any comments, please send a note to that effect as well.