Subject: [Ice] Trickle ICE Section 5

From: Bernard Aboba <[email-masked]>
Date: Mon, 31 Oct 2016 14:11:26 -0700

Receiving the Initial Offer

   When an agent receives an initial offer, it will first check if the
   offer or offerer indicates support for Trickle ICE as explained in
   Section 3 <https://tools.ietf.org/html/draft-ietf-ice-trickle-04#section-3>.
If this is not the case, the agent MUST process the offer
   according to Vanilla ICE procedures [rfc5245bis
<https://tools.ietf.org/html/draft-ietf-ice-trickle-04#ref-rfc5245bis>]
or offer/answer
   processing rules [RFC3264 <https://tools.ietf.org/html/rfc3264>] if
no ICE support is detected at all.

   If support for Trickle ICE is confirmed, an agent will automatically
   assume support for Vanilla ICE as well even if the support

   verification procedure in [rfc5245bis
<https://tools.ietf.org/html/draft-ietf-ice-trickle-04#ref-rfc5245bis>]
indicates otherwise.
   Specifically, the rules from [rfc5245bis
<https://tools.ietf.org/html/draft-ietf-ice-trickle-04#ref-rfc5245bis>]
would imply that ICE itself
   is not supported if the initial offer includes no candidates in the
   offer; however, such a conclusion is not warranted if the answerer
   can confirm that the offerer supports Trickle ICE and thus fallback
   to [RFC3264 <https://tools.ietf.org/html/rfc3264>] is not necessary.

   If the offer does indicate support for Trickle ICE, the agent will
   determine its role, start gathering and prioritizing candidates;
   while doing so, it will also respond by sending its own answer, so
   that both agents can start forming check lists and begin connectivity
   checks.

[BA] Most of this text seems more appropriate to the SIP draft than this one,

since it references RFC 3264.