Re: [rtcweb] Transports: RFC 4941 support?

Harald Alvestrand <harald@alvestrand.no> Fri, 21 March 2014 11:14 UTC

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Date: Fri, 21 Mar 2014 12:14:20 +0100
From: Harald Alvestrand <harald@alvestrand.no>
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Subject: Re: [rtcweb] Transports: RFC 4941 support?
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On 03/19/2014 04:41 PM, Simon Perreault wrote:
> Le 2014-03-19 11:21, Harald Alvestrand a écrit :
>>> The application needs to indicate if it wants a temporary address. If
>>> the host's policy (or configuration or network) does not support
>>> temporary addresses, the application won't get a temporary address.  I
>>> don't see why being silent helps?
>> What API is it using?
>>
>> With a little Googling, the system policy I was thinking of was the
>> policy in RFC 6724 ("Default Address Selection for IPv6"), in particular
>> section 5 rule 7: "Prefer  temporary addresses".
>>
>> I'm happy to say "it is a good idea for systems to implement the
>> recommendations of RFC 6724" (or some more 2119-like language). I
>> wouldn't want to claim that if a system has chosen to prefer
>> non-temporary addresses, it would have to change its non-conformance to
>> RFC 6724 in order to be conformant with RTCWEB specifications.
> IMHO it would be perfectly sensible to recommend the use of
> IPV6_PREFER_SRC_TMP [RFC5014].
>
> Simon
Interesting: This rule was reversed from 3484 to 6724 - 3484 preferred 
public, 6724 prefers temporary. 5014 claims that the default is 
PREFER_SRC_PUBLIC, which is not 6724 conformant. And RFC 5245 (ICE) 
contains a pointer to RFC 3484, recommending its use in address selection.

With this amount of misleading stuff in RFCs, I think it's best to say 
something after all.