Subject: [P2PSIP] No ICE Attach offer/answer

From: "Michael Chen" <[email-masked]>
Date: Mon, 17 May 2010 12:14:01 -0700

Hi,

In the current base-08 draft, section 5.5.1.1 has the following
definition:

   overlay_link
      corresponds to the OverlayLink production, Overlay Link protocols
      used with No ICE MUST specify "no ICE" in their description.

What is "description"? My suggestion is that this sentence need NOT to
single out no ICE. However, if one insists, this will be a good
revision:

   overlay_link
      corresponds to the OverlayLink production, Overlay Link protocols
      used with No ICE MUST specify DLTS-UDP-SR-NO-ICE(3) or
TLS-TCP-FH-NO-ICE(4).

I have a related problem. The last sentence of the "overlay_link"
definition says:

   overlay_link
      ...
      A single AttachReqAns MUST NOT include both candidates whose
      OverlayLink protocols use ICE (the default) and candidates that
      specify "no ICE".

Section 5.5.1.11 says,

   No-ICE is selected when either side has provided "no ICE" Overlay
Link candidates.

Peers that support ICE can also easily support No-ICE, but the above two
requirements have these implications:

1. In most cases, when peer A wants to Attach to peer X, peer A MUST
decide whether to send an ICE or No-ICE while knowing nothing about X
beyond its NodeId. It seems to me A has no choice but to send ICE
attach.

2. When connecting to a bootstrap node or any nodes with known public
IP, there is no need to send the Attach message. Just do D/TLS directly
to the nodes' IP and port number.

Then what is the use case for a No-ICE Attach?

Thanks

--Michael